Article

Effects of Prescribed Burning on Amphibian Diversity in a Southeastern U.S. National Forest

Wiley
Conservation Biology
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Abstract

Fire alters the abundance and diversity of many species, but its effects on amphibians are poorly known. We tested whether prescribed burning affected amphibian abundance and diversity within the Francis Marion National Forest, South Carolina, by monitoring assemblages at 15 temporary ponds with five different burn histories: 0, 1, 3, 5, and 12 years after burns. We also monitored terrestrial and aquatic environmental variables likely to influence amphibian diversity, such as leaf-litter depth, pond water chemistry, and distance to neighboring ponds. Fire had significant negative effects. Immediate effects ( burning during the study ) explained 12.8% and 10.8% of the variation in anuran and amphibian abundance, respectively, whereas short-term effects explained 31.8% and 24.6% of variation in amphibian species richness and evenness, respectively. Species richness increased and evenness decreased with time since burn, primarily because salamanders were rarely encountered at sites burned within 2 years. These sites had the shallowest leaf litter and highest soil temperature variances. Environmental factors unrelated to burning also significantly influenced amphibian diversity. Water chemistry explained 31.1% of variation in species richness, 32.2% of evenness, and>25% of anuran, salamander, and total amphibian abundances. Salamanders were most sensitive to water chemistry factors, particularly pH. Our results suggest that decreasing the frequency of prescribed burns from the current 2–3 years to 3–7 years will better maintain diverse amphibian and plant assemblages. Substituting growing-season burns for the current practice of winter and spring burns would avoid repeatedly interrupting amphibian breeding and would maintain the desired longleaf pine community.

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... We used a before-after-control-impact experimental design combined with mark-recapture to examine the impacts of prescribed fire on apparent survival, movement, and abundance (i.e., raw counts) of treefrogs in pine flatwoods in central Florida, US. To observe treefrogs, which use natural cavities to avoid desiccation and predation, we set polyvinyl chloride (PVC) pipes in trees as artificial refugia which they could enter and exit at will (Buchanan 1988;Boughton et al. 2000;Schurbon and Fauth 2003;Zacharow et al. 2003;Glorioso and Waddle 2014). While the pine flatwoods are home to four native treefrog species in central Florida, 99% of individuals observed in our study were one specialist species, the pinewoods treefrog (Dryophytes (Hyla) femoralis Bosc, Fig. 1) (Klaus and Noss 2016). ...
... Between 15 and 21 February 2021, we attached PVC pipes as treefrog refugia in the 12 chosen pine trees (Buchanan 1988;Boughton et al. 2000;Schurbon and Fauth 2003;Zacharow et al. 2003;Bartareau 2004;Glorioso and Waddle 2014). All pipes were 61 cm long, 3.8 cm internal diameter, 330 psi, white, bottom-capped, fitted with a drainage hole at 10 cm from the bottom and a screw hole at the top, and secured to the tree with a drill and bungee so they faced inward towards the marsh. ...
... The parabolic shape of this response and lack of an obvious mortality event post-fire across all treatments suggests these individuals descended back into the lower subcanopy, understory, and shrub layers once the plants regreened, which is consistent with other studies. While sampling at and below breast height in a similar system, Schurbon and Fauth (2003) observed a lower abundance of treefrogs in a <1-year TSF area compared with areas burned in the previous year. Given the high site fidelity and low death by fire observed, temporary refugia in the tall trees seem to be a dominant mechanism for this species persisting in a fire-prone landscape. ...
Article
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Background Pine flatwoods of the southeastern United States were shaped by frequent fires. Land managers use prescribed fires to control fuels but also to restore historical fire dynamics. Broad outcomes of this practice are well-understood, but impacts on many organisms are still being explored. Frogs, for example, have upland and wetland requirements, limited mobility, and skin susceptible to desiccation. Treefrogs spend most of their lives in uplands away from water. When fire approaches, animals may escape to an unburned area, shelter in place, or be killed by the fire. We examined which of these mechanisms is the prevailing short-term response for a specialist treefrog in a pyrogenic flatwood system. Results We assessed the short-term impacts of prescribed fire on the dynamics of an upland flatwood specialist, the pinewoods treefrog Dryophytes femoralis , using a replicated before-after-control-impact field experiment. We set pipes as treefrog refugia at 3 m, 6 m, 9 m, and 9 ⁺ m in 12 pine trees spread evenly across two treatments: reference trees in units burned in 2020 and trees in units with 2021 prescribed fire. Prescribed fires occurred on 16 April and 21 July 2021. Every 2 weeks between 5 March and 5 September, we checked pipes for frogs and assigned them unique color marks. We observed 78 individuals with 199 additional recaptures. We modeled abundance (as raw counts), survival, and vertical movement using mark-recapture methods, multi-state, and mixed linear models with a Bayesian framework. Survival and recapture were comparable among prescribed fire treatments, but abundances and movement probability varied. Frogs in trees in areas burned during the study were more likely to stay in place and less likely to descend to lower heights. We observed more frogs in trees after a 2021 fire compared to reference trees. Conclusions The prevailing mechanism for resiliency to fire for pinewoods treefrogs was migration up large pines, then likely recolonization to lower vegetation layers when plants regreen post-fire. This substantiates conclusions from other works that the integrity of mature pines is key to sustaining native biodiversity. Future work and management should consider the three-dimensional structure of habitat when developing burn prescriptions and study designs.
... With some taxa such as birds and plants, the relationships between prescribed fire and community health in these habitats are well understood (Bechtoldt and Stouffer 2005;Brockway and Lewis 1997). Conversely, there is uncertainty when it comes to the best practices for maintaining populations of amphibians and reptiles with prescribed fire (Schurbon and Fauth 2003;Means et al. 2004). Herpetofauna may also be more sensitive to negative regional impacts of habitat fragmentation and urbanization than other vertebrates as they typically occupy specific microhabitats and are poor dispersers, which makes proper management in protected, unbroken tracts of their respective ecosystems essential (Colino-Rabanal and Lizana 2012). ...
... Observations of Green Treefrogs in Indiana, USA, have shown that occurrence is dependent on open-canopied breeding sites, while a study in South Carolina, USA, found greater Green Treefrog occurrence and insect biomass in open canopy, suggesting that they also benefit from prey availability in areas of dense ground vegetation (Horn et al. 2005;Lodato et al. 2014). Conversely, a study by Schurbon and Fauth (2003) of 15 temporary ponds with varying burn histories suggested that fire had significant negative effects on amphibian abundance and richness, with Green Treefrogs being predominantly found in habitat that had not been burned in > 12 y and Squirrel Treefrogs showing no clear preference, being found in habitat burned < 1 and > 12 y prior. Our results suggest that Green and Squirrel Treefrogs are both associated with unburned habitats with denser canopies at the GBR, though our occupancy modeling does not suggest differences in occurrence or detection between burned and unburned sites. ...
... There may also be regional differences that drive the preference, or lack thereof, of treefrogs to open canopy habitats as warmer climates would not require open canopies to create favorable thermal conditions on the ground. There is less ambiguity in our finding of the association of Pinewoods Treefrogs with regularly burned habitat, as all sampled individuals were present in burned sites and available literature supports the association of this species with open-canopy or regularly burned habitat (Schurbon and Fauth 2003;Mohrman et al. 2005;Langford et al. 2007). ...
Article
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Wildland fire is necessary for maintaining and restoring Pine Savannas in the southeastern USA, but there is disagreement on best land management regimes for herpetofaunal communities in these areas. We recreated a 2004 sampling effort in the Grand Bay National Estuarine Research Reserve (GNDNERR) and Grand Bay National Wildlife Refuge (GNDNWR), south Mississippi, USA, to assess how amphibian and reptile assemblages differ in response to prescribed fire. We used Visual Encounter Surveys (VES), minnow traps, and polyvinyl chloride (PVC) tubes in three burned and three unburned sites. As in 2004, we detected more amphibians (67% of our sample) than reptiles and found more individuals in burned than unburned treatments. We found no differences in abundance, diversity, evenness, and richness between burned and unburned treatments, though a Principal Coordinates Analysis (PCoA) indicated that burned communities were more similar to one another than to unburned communities. An Indicator Species Analysis (ISA) corroborated the PCoA findings. In both studies, we found ground-dwelling frogs such as the Oak Toad (Anaxyrus quercicus) and Southern Cricket Frog (Acris gryllus) more often in burned habitats than unburned, though occupancy analyses suggested this may be due to these species having higher detection probabilities in burned than unburned habitat. Additional surveys and different sampling methods will be needed to determine if these species can truly be indications of Pine Savanna health.
... Recent studies [23] focused on the post-fire regrowth of vegetation and our photos taken in 2014 ( Figure 1) show that more severely burned areas are still in the process of overstory vegetation recovery. Even though high-severity fires have been shown to increase nutrient levels and productivity in aquatic environments [24] and increase diversity of understory plants in terrestrial environments [25], recently-burned habitats lack the type of canopy cover needed by many amphibian species [21,26]. Hence, there is an urgent need to create artificial refuges until the habitat required by amphibian species has had time to restore itself. ...
... Campbell et al. found that observations of green tree frogs (Hyla cinerea), pinewoods tree frog (Hyla femoralis), and squirrel tree frog (Hyla squirella) in PVC pipes were 6-to 10-fold higher during dry seasons than during wet seasons, suggesting that pipe refugia provided shelter from the dry and cold conditions [29]. Although PVC pipes have been widely used as artificial refuges and as a sampling tool in the southeast USA [26,[29][30][31][32], to our knowledge, studies have used PVC pipes to evaluate amphibian assemblages only under prescribed fire conditions [26,31]. ...
... Campbell et al. found that observations of green tree frogs (Hyla cinerea), pinewoods tree frog (Hyla femoralis), and squirrel tree frog (Hyla squirella) in PVC pipes were 6-to 10-fold higher during dry seasons than during wet seasons, suggesting that pipe refugia provided shelter from the dry and cold conditions [29]. Although PVC pipes have been widely used as artificial refuges and as a sampling tool in the southeast USA [26,[29][30][31][32], to our knowledge, studies have used PVC pipes to evaluate amphibian assemblages only under prescribed fire conditions [26,31]. ...
Article
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Amphibians are the most threatened vertebrate class based on the IUCN Red List. Their decline has been linked to anthropogenic activities, with wildfires being among the most conspicuous agents of habitat alterations affecting native amphibians. In 2011, the most destructive wildfire in Texas history occurred in the Lost Pines ecoregion of central Texas, USA, burning 39% of the 34,400 ha forest and drastically decreasing available habitats for many native wildlife species, including the green tree frog (Hyla cinerea). We investigated use of PVC pipes as artificial refuges for green tree frogs in different habitats within this post-fire pine forest. We monitored green tree frog use of small (diameter 38.1-mm, 1.5 inch) and large (diameter 50.8-mm, 2 inch) pipes located adjacent to, and 5 m from, ponds in burned and unburned areas over a 5-month period. We caught 227 frogs, 101 (24 adults and 77 juveniles) in burned and 126 (61 adults, 63 juveniles, and 2 unknown) in unburned areas. A relationship between pipe use by adults and/or juveniles and pipe location in burned versus unburned areas was found, but pipe use by adults and/or juveniles and pipe size were independent. Pipe use by adults and/or juveniles and pipe size were also independent. Juveniles were more frequently observed in pipes located adjacent to ponds. Our results confirmed that PVC pipes merit consideration as a simple, inexpensive, conservation tool to aid in restoration of green tree frog populations after high-severity wildfires. Such artificial refuges may be particularly important for survival of juveniles in severely altered post-fire habitats.
... No mundo todo, anfíbios são os tetrápodas menos estudados no que diz respeito à sua suscetibilidade ao fogo, sendo que a quase totalidade dos estudos publicados estão restritos aos Estados Unidos (e.g. Schurbon & Fauth, 2003;Langford et al., 2007) e à Austrália(e.g. Friend, 1993;Driscoll & Roberts, 1997). ...
... O fogo pode afetar populações de anfíbios tanto de maneira direta, matando indivíduos, quanto de maneira indireta, através de alteração do hábitat, por exemplo (Gresswell, 1999). O fogo altera significativamente diversas características do ambiente, tais como umidade e temperatura do solo, estrutura da vegetação, profundidade da serrapilheira, taxas de erosão e hidroperíodo de ambientes aquáticos (Cain et al., 1998, Schurbon & Fauth, 2003. Diversas características dos anfíbios os tornam sensíveis a mudanças no ambiente, e, seria de se esperar, que alterações ambientais provocadas por incêndios afetassem significativamente este grupo (Schurbon & Fauth, 2003). ...
... O fogo altera significativamente diversas características do ambiente, tais como umidade e temperatura do solo, estrutura da vegetação, profundidade da serrapilheira, taxas de erosão e hidroperíodo de ambientes aquáticos (Cain et al., 1998, Schurbon & Fauth, 2003. Diversas características dos anfíbios os tornam sensíveis a mudanças no ambiente, e, seria de se esperar, que alterações ambientais provocadas por incêndios afetassem significativamente este grupo (Schurbon & Fauth, 2003). ...
... Although longleaf pine savannas of the southeastern United States, and the wetland habitats embedded within them, are widely acknowledged as ecosystems dependent on frequent fire (every 1-3 years, on average, for the most fireexposed parts of the landscape; Platt 1999, Frost 2006, Stambaugh et al. 2011, Schurbon andFauth (2003:1338) asserted that "decreasing the frequency of prescribed burns from the current 2-3 years to 3-7 years will better maintain diverse amphibian and plant assemblages." That claim was based on their finding higher amphibian species richness (i.e., all amphibians grouped together) in wetlands not burned for 3-7 years. ...
... We categorized amphibians detected by Schurbon and Fauth (2003) and Schurbon (2000) as specialists or generalists (using the same criterion used for our study) then combined their data with ours and arranged it in a table by years-sincefire (time since last documented fire according to USFS records in forest stand where each species was detected). A pattern emerged; some generalist species were not found in recently burned sites and some specialist species were not found in long unburned sites (Table 1). ...
... If we had compared these sites with sites in lower-lying mesic hardwood stands, for example, our results would likely be different. Schurbon and Fauth (2003) reported higher total species richness in long-unburned sites, but all of their sites in the >8 years-since-fire category were located at lower elevation and on different soils than the sites in the <1 and 1 year-since-burn categories (Schurbon 2000), potentially confounding time since fire with edaphic or topographic factors. The sites used in our study were comparable to Schurbon and Fauth's (2003) <0 and 1 year-since-burn sites but dissimilar to their >8 year-sinceburn sites based on soil types and elevation. ...
Article
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Available habitat within a landscape is often more limited for specialist species than for generalists. Therefore, specialists are potentially more vulnerable to extinction. The goal of our study was to better understand the ephemeral wetland habitat associations of specialist and generalist amphibians within a longleaf pine landscape in the southeastern United States. We also sought to determine specialist (e.g., oak toad [Anaxyrus quercicus], Mabee's salamander [Ambystoma mabeei], pine woods treefrog [Hyla femoralis], carpenter frog [Lithobates virgatipes]) and generalist (e.g., spotted salamander [Ambystoma maculatum], Cope's gray treefrog [Hyla chrysoscelis], southern leopard frog [Lithobates sphenocephalus]) species' responses to specific habitat restoration treatments. From 2005-2010, we examined the relationship between aquatic specialist and generalist amphibian species occupancy and wetland vegetation structure. We measured vegetation and amphibian responses to prescribed fire and vegetation mulching (a fire surrogate), plus a combination of mulching and burning. Untreated controls were wetlands that had not burned for 4-15 years. We combined data from this study and a previous study to elucidate patterns in amphibian assemblages in relation to fire history. Specialist relative species richness was highest when canopy openness was high and leaf litter depth was low, conditions best achieved by mulching plus burning. Some specialist species were not detected in wetlands with >8 years since fire, and some generalist species were not detected in wetlands with <2 years since fire, indicating that as vegetation structure changes with time since fire, there is a corresponding shift in the amphibian assemblage. Important patterns in species distributions can be overlooked if relationships to environment and responses to habitat change are too generalized and do not account for shifts in community composition. For conservation of longleaf pine specialist species, we recommend that uplands continue to be prescribed-burned on a 1-3-year return interval. Burning should occur during the early growing season when possible to maximize the probability that wetland basins burn. In cases where species of high conservation value are at imminent risk of extinction, we recommend a combination of mulching and burning to most quickly restore suitable habitat structure.
... Fire also can increase the pH of aquatic systems by releasing alkaline cations (Ca 2+ , Mg 2+ , K + , Na + ) stored in plants (DeBano et al., 1998;Battle and Golladay, 2003;Certini, 2005). The pH of potential breeding habitats is an important factor determining amphibian distributions, given the interspecific variation in tolerance to acidity during embryonic and larval development (Freda andDunson 1984, 1986;Brodman et al., 2003;Schurbon and Fauth, 2003). The magnitude of these and other changes in water chemistry following a fire depends on the amount and timing of post-fire rainfall (Bozek and Young, 1994), the catchment area of the water body (Minshall et al., 1989), nutrient solubility, the season of burn, and the intensity and severity of the burn (Battle and Golladay, 2003). ...
... The mean number of fires in the past 50 yr was 4.5 6 1.7 in ponds burned in the past 4 mo (not counting the most recent fire), 1.8 6 1.0 in ponds burned 3-4 yr ago, and 1.5 6 1.0 in ponds burned 11 yr ago. This means that our results may partly reflect how fire frequencies over long time periods affect Oak Toad larvae (Schurbon and Fauth, 2003;Means et al., 2004;Robertson and Ostertag, 2004;Schurbon and Fauth, 2004), although the results still indicate that either recent burning, more-frequent fires, or both are better for recruitment. Greenberg and Tanner (2005) found higher Oak Toad recruitment in ponds within hardwoodinvaded upland matrices than in ponds within fire-maintained pine flatwoods. ...
... The mean number of fires in the past 50 yr was 4.5 6 1.7 in ponds burned in the past 4 mo (not counting the most recent fire), 1.8 6 1.0 in ponds burned 3-4 yr ago, and 1.5 6 1.0 in ponds burned 11 yr ago. This means that our results may partly reflect how fire frequencies over long time periods affect Oak Toad larvae (Schurbon and Fauth, 2003;Means et al., 2004;Robertson and Ostertag, 2004;Schurbon and Fauth, 2004), although the results still indicate that either recent burning, more-frequent fires, or both are better for recruitment. Greenberg and Tanner (2005) found higher Oak Toad recruitment in ponds within hardwoodinvaded upland matrices than in ponds within fire-maintained pine flatwoods. ...
Article
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The direct and indirect effects of fire on different life stages of amphibians are poorly understood and difficult to predict given interspecific variation in physiology and life history. We investigated how time-since-fire (TSF) of seasonal ponds embedded within Florida scrub habitat affected growth, development, and survival of larval Oak Toads (Anaxyrus quercicus). We selected 12 ponds at Archbold Biological Station on the southern Lake Wales Ridge, Florida: four burned within the last 4 mo, four burned 3–4 yr ago, and four burned 11 yr ago. We hatched and reared three clutches of Oak Toads in the laboratory for 2 wk and then sorted larvae into groups of 24 having equal representation from each clutch. We randomly assigned groups of larvae to 0.22-m 3 mesh field enclosures in each pond (n = 2–3 enclosures per pond) and measured environmental variables that might contribute to observed amphibian responses including pH, temperature, and periphyton growth. After 15 d, when larvae began metamorphosing, mean survival was significantly higher in the most-recently burned ponds. The TSF did not have a significant effect on developmental stage or tadpole size, although Oak Toad larvae tended to develop faster in the most-recently burned ponds. Although all ponds were acidic (pH < 4.3), there was a trend toward higher pH in the more-recently burned ponds, and survival was significantly positively correlated with pH. Overall our results suggest that performance and recruitment of larval Oak Toads are higher in recently burned ponds.
... When results were summarized, no research gaps were identified as having the highest priority (Platt et al. 1988, Waldrop and Lloyd 1991, White et al. 1991, Streng et al. 1993), but the long-term impacts to amphibian communities are unknown. Similarly, the response of amphibian communities and wetland ecology to annual or bi-annual burns versus longer fire frequencies has not been tested over a long period and is still debated (Schurbon and Fauth 2003, Means et al. 2004, Robertson and Ostertag 2004, Schurbon and Fauth 2004. ...
... Wildlife Conservation Strategy ranked "incompatible fire" as one of the highest overall threats across all Florida's terrestrial habitat (FWC 2005). Most land managers recognize the necessity of fire to maintain the longleaf pine ecosystem, but there is debate regarding the importance of fire season versus fire frequency (Bishop and Haas 2005) and as to the appropriate fire frequency (Schurbon and Fauth 2003, Means et al. 2004, Robertson and Ostertag 2004. ...
Technical Report
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Studies on the herpetofauna of ephemeral ponds have been conducted across the state. However, existing data on ephemeral pond-breeding amphibians are scattered and are not readily available to land managers, policy makers, scientists, and other interested stakeholders. This project was designed to synthesize existing information for these species in order to develop management strategies for ephemeral ponds, particularly as they pertain to amphibian conservation. Involving stakeholders during this process provided additional input as well as disseminated the information in a manner that facilitated discussion. Other project objectives included developing a geo-referenced database for ephemeral pond-breeding amphibian research and surveying ephemeral ponds. The project focused specifically on 5 Species of Greatest Conservation Need (SGCN): flatwoods salamander (now two species-Ambystoma bishopi and A. cingulatum), tiger salamander (A. tigrinum), striped newt (Notophthalmus perstriatus), ornate chorus frog (Pseudacris ornata), and gopher frog (Rana capito). This final report contains results from a 3-year project.
... We found no studies on the impacts of amphibians, reptiles or mammals within UK upland areas. Research from North America and Australia demonstrate prescribed burning has the potential to affect the overall abundance and diversity of species of amphibian (Schurbon and Fauth, 2003;Perry et al., 2012), reptiles (Gorissen et al., 2015;Harper et al., 2016) and mammals (Burrows and McCaw, 2013;Lashley et al., 2015;Harper et al., 2016) and this should constitute a key area for future study in the UK. ...
... Future research should progress in these new directions to provide a greater knowledge of ecosystem responses to fire. Research from outside of the UK can provide a useful context in these areas (Schurbon and Fauth, 2003;Perry et al., 2012;Gorissen et al., 2015;Lashley et al., 2015;Harper et al., 2016), but its applicability to the UK needs to be validated. ...
Article
Full-text available
The impacts of vegetation fires on ecosystems are complex and varied affecting a range of important ecosystem services. Fire has the potential to affect the physicochemical and ecological status of water systems, alter several aspects of the carbon cycle (e.g. above- and below-ground carbon storage) and trigger changes in vegetation type and structure. Globally, fire is an essential part of land management in fire-prone regions in, e.g. Australia, the USA and some Mediterranean countries to mitigate the likelihood of catastrophic wildfires and sustain healthy ecosystems. In the less-fire prone UK, fire has a long history of usage in management for enhancing the productivity of heather, red grouse and sheep. This distinctly different socioeconomic tradition of burning underlies some of the controversy in recent decades in the UK around the use of fire. Negative public opinion and opposition from popular media have highlighted concerns around the detrimental impacts burning can have on the health and diversity of upland habitats. It is evident there are many gaps in the current knowledge around the environmental impacts of prescribed burning in less fire-prone regions (e.g. UK). Land owners and managers require a greater level of certainty on the advantages and disadvantages of prescribed burning in comparison to other techniques to better inform management practices. This paper addresses this gap by providing a critical review of published work and future research directions related to the impacts of prescribed fire on three key aspects of ecosystem services: (i) water quality, (ii) carbon dynamics and (iii) habitat composition and structure (biodiversity). Its overall aims are to provide guidance based on the current state-of-the-art for researchers, land owners, managers and policy makers on the potential effects of the use of burning and to inform the wider debate about the place of fire in modern conservation and land management in humid temperate ecosystems.
... For instance, thermal changes can negatively affect development and survival, especially species in riparian forests that are adapted to colder temperatures [57,59,65]. Other conditions resulting from a prescribed fire that can have negative associated effects on salamander growth and abundance in riparian forests include an increase in exposure to ultraviolet-B, sedimentation due to fire-induced erosion, loss of moist leaf litter, removal of woody debris, and declines in local insect populations [57,135,136]. ...
... Human-caused disturbance, including timber harvest, prescribed fires, urbanization, road construction, and habitat fragmentation, alter these habitat factors within riparian forests. Timber harvest can increase salamander susceptibility to desiccation, while prescribed fire can result in the loss of moist leaf litter, thermal changes, and removal of woody debris [57,69,118,135,136]. Urbanization impacts stream salamanders, and roads contribute to habitat fragmentation, which restricts dispersal and may lead to extirpations of local species [52,99,[143][144][145]148]. ...
Article
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Salamanders and riparian forests are intimately interconnected. Salamanders are integral to ecosystem functions, contributing to vertebrate biomass and complex food webs in riparian forests. In turn, these forests are critical ecosystems that perform many environmental services, facilitate high biodiversity and species richness, and provide habitat to salamander populations. Due to the global decline of amphibians, it is important to understand, as thoroughly and holistically as possible, the roles of environmental parameters and the impact of human activities on salamander abundance and diversity in riparian forests. To determine the population responses of salamanders to a variety of environmental factors and anthropogenic activities, we conducted a review of published literature that compared salamander abundance and diversity, and then summarized and synthesized the data into general patterns. We identify stream quality, leaf litter and woody debris, riparian buffer width, and soil characteristics as major environmental factors influencing salamander populations in riparian forests, describe and explain salamander responses to those factors, and discuss the effects of anthropogenic activities such as timber harvest, prescribed fires, urbanization, road construction, and habitat fragmentation. This review can assist land and natural resource managers in anticipating the consequences of human activities and preparing strategic conservation plans.
... Herpetofauna and small mammal diversity, abundance, and activity have been correlated with changes in microhabitat features such as leaf litter depth, soil moisture, and vegetation structure (deMaynadier and Hunter, 1995;Schurbon and Fauth, 2003), and amount and distribution of coarse woody debris following forest management (Davis et al., 2010;Loeb, 1999;Owens et al., 2008;Riffell et al., 2011). However, few studies address responses of herpetofauna or small mammals to specific management activities with appropriate control stands and these studies have not been pooled for region-wide analysis and management recommendations. ...
... Prescribed fire and selective herbicide can improve habitat quality in intensively managed pine stands for many wildlife species (Sladek et al., 2008;Thompson, 2002;Wigley et al., 2000;Woodall, 2005), including conditions for pine-grassland birds in decline such as Bachman's sparrow (Aimophila aestivalis), brownheaded nuthatch, and northern bobwhite (Colinus virginianus; Burger et al., 1998;Masters et al., 2001;Singleton et al., 2013), as represented by greater bird diversity and abundance of ground nesting birds. However, prescribed fire's effects on soil moisture and temperature, vegetation structure, leaf-litter depth, wetland hydroperiod, and refugia can have short-term negative effects on some herpetofaunal species (Grant et al., 1994;Schurbon and Fauth, 2003), as seen by variable responses between reptiles and amphibians in our meta-analysis. Many invertebrates included in this meta-analysis (e.g., Iglay et al., 2012a) were forest-associated species that preferred moist to wet soil typical of closed-canopy forests (Larochelle and Larviére, 2003). ...
Article
Open canopy conditions in southeastern pine (Pinus spp.) forests were historically maintained by frequent fire and other disturbances, without which midstory hardwoods create closed canopy conditions limiting value of pine stands for many endemic, disturbance-adapted species. Intensively managed pine forests, which comprise 19% of forests in the southeastern U.S., can emulate historical open pine conditions, providing appropriate vegetation structure and composition for many endemic species. However, exact mechanisms for producing and maintaining open pine conditions and subsequent effects on biodiversity have not been examined across regions and stand ages. To better inform managers about options for providing open pine conditions in intensively managed pine stands, we used meta-analyses to examine biodiversity and open pine focal species responses to 5 stand establishment intensities and 4 mid-rotation practices (prescribed fire, selective herbicide, fire and herbicide combination, and thinning). We calculated 1742 biodiversity and 169 open pine focal species effect sizes from 42 publications of manipulative studies at 14 unique study sites in managed loblolly pine (P. taeda L.) forests in the Atlantic and Gulf Coastal Plains of the southeastern U.S. We quantified diversity and abundance responses by taxa and management practices for vegetation, birds, amphibians, reptiles, small mammals, and invertebrates. Diversity and abundance responses generally decreased as stand establishment intensity increased, but those reductions appeared to be short-term (<3. years). Birds and open pine focal species responded positively to chemical stand establishment relative to a mechanically-prepared control. Thinning elicited positive diversity and abundance responses from reptiles and small mammals. Effects of prescribed fire, selective herbicide, and their combination on biodiversity responses varied by taxa (e.g., following fire, vegetative and avian diversity increased but amphibian and invertebrate diversity decreased). Further research is warranted on under-represented taxa (e.g., herpetofauna and invertebrates) in literature and long-term effects of forest management on biodiversity. Understanding how silvicultural management practices produce and maintain open pine forest conditions and influence biodiversity responses is necessary to inform opportunities for open-pine wildlife communities in working forested landscapes.
... The correlations between fire heterogeneity and reptiles found in this study were very mixed with a high amount of variation, supporting previous findings of variability in faunal responses that lead to recommendations of fire mosaics (Bock & Bock 1978;Fox 1982;Letnic 2002;Schurbon & Fauth 2003;Briani et al. 2004;Bleby et al. 2009;Litt & Steidl 2011). Reptile composition was best explained by site level variables, suggesting an importance of heterogeneity at the broader scale for overall community structure. ...
Thesis
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As an ecological process fire plays a global role in structuring ecosystems and their constituent fauna and flora. Fire is also regularly applied as a landscape management tool and altered fire regimes affect global biodiversity. Fire can have a marked influence on vegetation composition and structure with resultant flow on impacts on faunal communities. However, faunal responses to fire are often quite varied and management recommendations of appropriate fire regimes therefore generally include utilising a fire mosaic approach to fire management. This thesis investigates the relationship between variable fire regimes, vegetation composition, condition and structure, and ground-dwelling vertebrate faunal communities. The literature review (Chapter 1) revealed several gaps in current knowledge. This included a lack of detailed knowledge on the effects of variable fire regimes, including repeated management burns and fire mosaics, representative of multiple fire parameters (time since fire, number of fires, fire interval and fire type), on ecosystem biota. This was particularly evident for subtropical ecosystems. To analyse the effects of repeated burns, fire exclusion and wildfire, this study targeted one of the longest running fire experiments in Australia, at Bauple State Forest, where fire treatments have been applied annually since 1952 and triennially since 1973. Additional dry eucalypt forest sites at St Mary and Tiaro State Forests were included that represented variable fire management practices. Detailed fauna trapping surveys and vegetation assessments were completed on 35 plots across eight fire treatments at all three sites. Additionally, a broader scale GIS analysis of fire history was done across the three forests with surveys undertaken at an additional 74 sites allowing a comparison of reptile communities, forest condition and structure among variable fire regimes at multiple scales. To quantify the structural and compositional influences that fire has on vegetation communities in subtropical systems, Chapter 3 involved a detailed analysis of the communities within the three dry eucalypt forests. Fire treatments significantly altered vegetation community diversity, structure and composition. Annual burning resulted in reduced floral diversity among all strata and reduced structural heterogeneity in the ground and shrub layers. Long unburned areas were more diverse but had lower canopy heterogeneity. Wildfires did not significantly impact the vegetation community.Consistent with previous research, this chapter found that frequent, repeated burning can reduce the diversity and structural complexity of forests. The effects of disturbance (fire and logging) on forest condition and forest variables across the landscape were investigated in Chapter 4 using a biodiversity condition assessment toolkit among 63 plots. Forest variables and overall condition were correlated with historical disturbance patterns, derived from GIS, among Regional Ecosystems (RE), including time since fire, number of fires, fire interval, fire type and years since logging. The majority of forest variables were negatively affected by more frequent (61.5% of variables), or recent fire disturbances (76.9% of variables). The most pronounced negative impacts occurred for tree species richness, and two key habitat attributes for fauna including coarse woody debris and litter cover, which were maximised in long unburned areas highlighting the importance of maintaining long unburned refuges in the landscape. Chapter 5 investigated the response of reptile and anuran communities, surveyed at 35 trapping plots, to different fire regimes and habitat characteristics quantified in Chapter 3. Reptiles were more vulnerable to fire impacts than anurans, particularly frequent fires (annual burning) which reduced the abundance of several species; however, species were generally not affected by wildfire. Species such as Lampropholis delicata and Eulamprus martini favoured long unburned areas, however, other species, i.e. Carlia p. pectoralis, preferred frequently and recently burned sites. Anurans, on the other hand appeared to be resilient to fires, corroborating previous studies on this taxon as they are able to retreat into moist microhabitats to survive. The ‘risk’ and ‘impact’ of fires to individual species was interpreted using a conceptual model that was able to categorise species as either tolerant or resilient to fire. These species-specific responses are important considerations when planning fire management guidelines that advocate frequent burning, as some species may be negatively affected. In a parallel analysis, Chapter 6 assessed small mammal communities across the three sites and their response to variable fire regimes and habitat parameters. Mammals generally were not strongly influenced by fire but had highly variable responses which made it difficult to determine the factors influencing either species richness or abundance. It therefore appears likely that small mammal communities are not being negatively affected by repeated burning practices or infrequent wildfire. However, species were often correlated with habitat heterogeneity characteristics, highlighting the importance of maintaining a structurally diverse habitat that supports a variety of mammal species. As such, the indirect effects of fires may lead to a reduction in ideal habitat for certain mammals. In Chapter 7, reptile communities were assessed across the landscape and correlated with various fire parameters and forest variables from Chapter 4. Number of fires, time since fire and fire type were key predictors for overall reptile abundance, as well as the abundance of four of the seven common study species. Overall abundance was negatively affected by number of fires and it also altered the overall reptile assemblage, while at a species level Carlia spp. were negatively associated with time since fire. Fire was generally a stronger predictor of reptile responses than habitat parameters with only shrub cover found to be negatively associated with Carlia spp. A reduction in total number of fires of some areas and increase in variability of burn intervals may support a greater diversity and abundance of reptiles in parts of the landscape where the total number of fires is high. Fire heterogeneity was quantified within fire regimes across multiple scales in Chapter 8, using the variation in time since fire, number of fires, fire interval and unique (combination) fire mosaic regimes derived from GIS. Heterogeneity at the patch, local and site scales calculated from the Shannon-Wiener diversity index was weakly correlated with reptile communities and the heterogeneity measures appeared to be a poor surrogate of ‘fire diversity’. While this heterogeneity measure could not explain patterns in reptile communities, it is important to note that it captures only one element of landscape ‘pyrodiversity’. As other fire parameters including fire type revealed significant responses amongst reptiles, the specific nature of any biodiversity response to pyrodiversity appears linked to both scale and specific parameters used. This thesis has demonstrated that aspects of the vegetation community as well as faunal species, favoured different fire regimes, where some species and structural characteristics preferred frequently burned areas while others (although more often than not) preferred infrequently burned or long unburned areas. Support is provided for the suggestion that a mix of frequently burned, infrequently burned and long unburned areas across the landscape will maximise floral and faunal communities, and help meet management goals of maintaining biodiversity. However, the scale of these unburned refuges is an important question that requires more research.
... and exit at will (Buchanan 1988, Boughton et al., 2000, Schurbon and Fauth 2003, Zacharow et al. 2003 Glorioso and Waddle 2014). While the pine flatwoods are home to four native treefrog species in central 104 ...
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Background: Pine flatwoods of the southeastern United States were shaped by frequent fires. Land managers use prescribed fires to control fuels but also to restore historical lightning-caused fire dynamics. Broad outcomes of this practice are well-understood, but impacts on many organisms are still being explored. Frogs, for example, have upland and wetland requirements, limited mobility, and skin susceptible to desiccation. Treefrogs spend most of their lives in uplands away from water. When fire approaches, animals may escape to an unburned area, hide in place, or be killed by the fire. We examined which of these mechanisms is the prevailing short-term dynamic for persistence of a specialist treefrog in a pyrogenic flatwoods system. Results: We assessed short-term impacts of prescribed fire on the dynamics of an upland flatwoods specialist, the pinewoods treefrog Dryophytes femoralis, using a replicated before-after-control-impact field experiment. We set pipes as treefrog refugia at 3 m, 6 m, 9 m, and 9⁺ m in 12 pine trees spread evenly across two treatments: reference trees in units burned in 2020 and trees in units with 2021 prescribed fire. Prescribed fires occurred April 16 and July 21, 2021. Every two weeks between 5 March and 5 September we checked pipes for frogs and assigned them unique color marks. We observed 78 individuals with 199 additional recaptures. We modeled abundance (as raw counts), survival, and vertical movement using mark-recapture methods, multi-state, and mixed linear models with a Bayesian framework. Survival and recapture were comparable among prescribed fire treatments, but abundances and movement probability varied. Frogs in trees in areas burned during the study were more likely to stay in place and less likely to descend to lower heights. We observed more frogs in trees after a 2021 fire compared to reference trees. Conclusions: The prevailing mechanism for resiliency to fire for pinewoods treefrogs was migration up large pines, then likely recolonization to lower vegetation layers when they regreen post-fire. This substantiates conclusions from other works that integrity of mature pines is key to sustaining native biodiversity. Future work and management should consider the three-dimensional structure of habitat when developing burn prescriptions and study designs.
... and exit at will (Buchanan 1988, Boughton et al., 2000, Schurbon and Fauth 2003, Zacharow et al. 2003 Glorioso and Waddle 2014). While the pine flatwoods are home to four native treefrog species in central 104 ...
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Background: Pine flatwoods of the Southeast United States evolved with frequent wildfires. Land managers today mostly use prescribed burns to control fuels but also to restore historical lightning-caused wildfires dynamics. Though coarse outcomes of this practice are well-understood, fine scale impacts on many animal assemblages are still being explored. Frogs, for example, have upland and wetland requirements, limited mobility, and skin susceptible to desiccation and chemicals. Treefrogs, which are typically nontargeted for management, spend most of their lives in uplands away from water. When fire approaches, these animals will escape to an unburned area, hide in place, or die. Results: We assessed impacts of prescribed fire on the dynamics of an upland flatwoods specialist, the pinewoods treefrog Dryophytes femoralis using a replicated before-after-control-impact field experiment. Using single rope technique and climbing equipment, we set PVC pipes as treefrog refugia at 3m, 6m, 9m, and 9+m in Longleaf Pines, Pinus palustris (n=12 tress). Three trees were selected in each patch per treatment: two unburned and two burned patches during the 2021 burning season (n=4 patches). Every two weeks between March and September we checked pipes for frogs and assigned them unique Visible Implant Elastomer (VIE) marks. We obtained data from 76 individuals with an additional 198 recaptures. Using mark-recapture methods and mixed linear models with Bayesian framework, we modeled abundance, survival, and vertical movement. Survival and recapture were comparable among treatments, but abundance, new frogs and probability of moving up or down a tree varied. Frogs in trees in burned units were more likely to stay in place and less likely to descend to lower heights. We observed an increased probability of finding new frogs and more abundance in trees after a fire compared to unburned controls. Conclusions: We found the prevailing mechanism for resiliency to fire for pinewoods treefrogs was migration up large pines, then recolonization of the shrub layer when it regreens post-fire. This finding substantiates conclusions from other works that integrity of mature pines is key to sustaining native biodiversity. Future work and management should consider the three-dimensional structure of habitat when developing burn prescriptions and study designs.
... In addition to reducing coarse materials, fire may also reduce the amount of accumulated leaf litter. The loss of litter may cause amphibians to lose migration paths and be placed at greater risk of predation and desiccation (Schurbon and Fauth 2003). While fire may have negative short term effect on certain amphibian species, it can help maintain general habitat types for species living in glade and long-leaf pine communities (Brisson et al. 2003, Schurbon andFauth 2004) . ...
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In the tallgrass prairie region of North America, grasslands are often burned on a rotational schedule to prevent the encroachment of woody species and maintain the vigor of plant communities. Although prescribed fire practitioners often consider the effects of fire on plant communities, the effects of fire on wildlife are also important. Practitioners as well as park visitors inquire about the effects of fire on birds, deer, and other animals of interest. Many wildlife species focus on vegetation structure in choosing suitable habitats, and fire can temporarily alter that structure. Wildlife species have varying habitat needs, and therefore, a variety of responses to fire. To accommodate the variety of habitat needs for wildlife within grassland, fire can be implemented heterogeneously. For example, varying the time of year a burn occurs, and burning only portions of the habitat in a single year can help sustain populations. Monitoring programs aimed at quantifying populations and acceptable levels of mortality for species of interest may also help fire programs adapt to help wildlife populations thrive. This document provides information about the ability of birds, mammals, and herpetofauna to escape or survive fire. We also describe how fire induced changes to habitat can affect groups of animals and a suite of individual species.
... Prescribed fire is typically less damaging for amphibian populations, as for any other group of organisms, by virtue of its relatively low severity. However, Schurbon and Fauth (2003) demonstrated its tangible impact by monitoring assemblages at 15 temporary ponds in South Carolina with different burn histories. Here, the immediate fire effects respectively explained 10.8% and 12.8% of variation in the abundances of amphibian in general and of anurans in particular. ...
Article
Fire has always been a driving factor of life on Earth. Now that mankind has definitely joined the other environmental forces in shaping the planet, lots of species are threatened by human-induced variation in fire regimes. Soil-dwelling organisms, i.e., those organisms that primarily live in soil, suffer the numerous and different consequences of fire occurrence that are, however, often overlooked compared to those on vegetation and wildlife. Most of these organisms live in the uppermost soil layer, where fire-imposed temperatures on the ground are the highest insofar as they are lethal or dangerously upset natural habitats. This contribution is a reasoned collation of findings from a number of works conducted worldwide that aims to gain insight into the immediate and longer-term impacts of single or repeated wild or prescribed fires on one group of soil-dwelling organisms or more. In fire-prone ecosystems, fire is a controlling factor of soil biota biodiversity and activity, but also where it is infrequent its ecological footprint can be substantial and lasting. Generally, the immediate fire impact on soil biota is strictly related to the peak temperatures reached on the ground and their duration, and on a set of soil properties and water content. Vertebrates can escape overheating death by running away, searching for wet niches or burrowing deep into soil. Invertebrates and microorganisms, which have little or no mobility, succumb more easily to fire, but make up for this intrinsic vulnerability thanks to their greater fecundity at the population level. Fire or burn severity, which can generally be defined as loss of organic matter aboveground and belowground, is the key factor of the indirect fire effects on soil-dwelling biota; whereas controlled burns do not often imply any substantial and lasting shift from the original situation, extreme and vast wildfires can have major consequences that may be severer than direct killing. In fact lairs are devastated, nutrient pools are heavily affected, food webs are upset, soil temperature and moisture regimes change, and toxic pyrogenic compounds remain in soil. All types of organisms can recolonise the burned area from their sanctuaries, provided that land use does not change, e.g., to pastures or arable fields, and prompt enough vegetation re-sprouting and/or encroachment prevent substantial soil erosion. Each major taxon has genera or species with useful traits and behaviours to resist fire or to recover from its unwelcome environmental legacy sooner than others. If burned soil does not undergo other fires that occur too closely together for the typical fire regime of that particular area, most of its living components are generally capable of returning to pre-fire levels in times that depend on a series of factors, such as fire severity and post-fire rainfall.
... É importante ressaltar que populações de anfíbios podem variar em tamanho de um ano para outro, devido a secas, temperaturas extremas ou predação, o que é um fenômeno natural e até previsível. HEYER, 1969;EDMUNDS, 1974;SAZIMA, 1974;SAZIMA, 1975;CARDOSO & SAZIMA, 1976;WELLS, 1977;SAZIMA, 1978;RYAN, 1985;HÖDL & GOLLMANN, 1986;BRODIE JR. & NUSSBAUM, 1987;HEYER et al. 1988;WEYGOLDT, 1989;CARDOSO & VIELLIARD, 1990;HADDAD, 1991;STEWART & RAND, 1991;MÁRQUEZ et al., 1993;MARTINS et al., 1993;SEBBEN et al., 1993;ROSSA-FERES & JIM, 1994;AZEVEDO-RAMOS, 1995;WAYE & SHEWCHUK, 1995;VIELLIARD & CARDOSO, 1996;HADDAD & BASTOS, 1997;MICHAEL, 1997;MANZANILLA et al., 1998;MARTINS et al., 1998;ZAMPROGNO et al., 1998;GRESSWELL, 1999;MCDIARMID & ALTIG, 1999;HADDAD & SAWAYA, 2000;PAPP & PAPP, 2000;WILLIAMS et al., 2000;ABBADIÉ-BISOGNO et al., 2001;BOURNE, 2001;GRAMAPUROHIT et al., 2001;GRANT, 2001;MARTINS, 2001;ROSSA-FERES & JIM, 2001;SYMULA et al., 2001;YOUNG et al., 2001;KWET & SOLÉ, 2002;PEARL & HAYES, 2002;CANALE & LINGNAU, 2003;COCHRAN & COCHRAN, 2003;COLLINS & STORFER, 2003;KIZIRIAN et al., 2003;SCHURBON & FAUTH, 2003;TOLEDO, 2003;VENCES et al., 2003;ETEROVICK & SAZIMA, 2004;HARTMANN, 2004;ETEROVICK et al., 2005;TOLEDO et al., 2006;CANELAS & BERTOLUCI, 2007;DINIZ-FILHO et al., 2008;LEITE et al., 2008;PIMENTA et al., 2008;BAÊTA & SILVA, 2009;SILVA et al., 2009;VERDADE et al., 2009;BRCKO et al., 2013;FONSECA et al., 2011;SÃO-PEDRO & FEIO 2011;HADDAD et al., 2013;PIRANI et al., 2013;SOUZA et al., 2015.  Regional human culture may represent an additional threat to amphibians. ...
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O livro Anfíbios Anuros da Serra do Cipó traz o resultado de extensa pesquisa de campo onde foi possível registrar 58 espécies (18 a mais quando comparado com o estudo de 2004). Essa nova edição se justifica particularmente pelo grande aprofundamento do conhecimento acerca da anurofauna da Serra do Cipó nos últimos 15 anos. Espécie descrita recentemente (Physalaemus claptoni) constam no livro o que torna a obra atualizada.
... É importante ressaltar que populações de anfíbios podem variar em tamanho de um ano para outro, devido a secas, temperaturas extremas ou predação, o que é um fenômeno natural e até previsível. HEYER, 1969;EDMUNDS, 1974;SAZIMA, 1974;SAZIMA, 1975;CARDOSO & SAZIMA, 1976;WELLS, 1977;SAZIMA, 1978;RYAN, 1985;HÖDL & GOLLMANN, 1986;BRODIE JR. & NUSSBAUM, 1987;HEYER et al. 1988;WEYGOLDT, 1989;CARDOSO & VIELLIARD, 1990;HADDAD, 1991;STEWART & RAND, 1991;MÁRQUEZ et al., 1993;MARTINS et al., 1993;SEBBEN et al., 1993;ROSSA-FERES & JIM, 1994;AZEVEDO-RAMOS, 1995;WAYE & SHEWCHUK, 1995;VIELLIARD & CARDOSO, 1996;HADDAD & BASTOS, 1997;MICHAEL, 1997;MANZANILLA et al., 1998;MARTINS et al., 1998;ZAMPROGNO et al., 1998;GRESSWELL, 1999;MCDIARMID & ALTIG, 1999;HADDAD & SAWAYA, 2000;PAPP & PAPP, 2000;WILLIAMS et al., 2000;ABBADIÉ-BISOGNO et al., 2001;BOURNE, 2001;GRAMAPUROHIT et al., 2001;GRANT, 2001;MARTINS, 2001;ROSSA-FERES & JIM, 2001;SYMULA et al., 2001;YOUNG et al., 2001;KWET & SOLÉ, 2002;PEARL & HAYES, 2002;CANALE & LINGNAU, 2003;COCHRAN & COCHRAN, 2003;COLLINS & STORFER, 2003;KIZIRIAN et al., 2003;SCHURBON & FAUTH, 2003;TOLEDO, 2003;VENCES et al., 2003;ETEROVICK & SAZIMA, 2004;HARTMANN, 2004;ETEROVICK et al., 2005;TOLEDO et al., 2006;CANELAS & BERTOLUCI, 2007;DINIZ-FILHO et al., 2008;LEITE et al., 2008;PIMENTA et al., 2008;BAÊTA & SILVA, 2009;SILVA et al., 2009;VERDADE et al., 2009;BRCKO et al., 2013;FONSECA et al., 2011;SÃO-PEDRO & FEIO 2011;HADDAD et al., 2013;PIRANI et al., 2013;SOUZA et al., 2015.  Regional human culture may represent an additional threat to amphibians. ...
... However, wild fire can pose a threat to local amphibian pop ulations as fire intensity and frequency increases (Hossack and Pilliod 2011, Westgate et al. 2018. Amphibian responses to fire are dependent on their natural history and habitat requirements, and may be affected by intensity, frequency, and timing of a fire (Pilliod et al. 2003, Schurbon and Fauth 2003, Hossack and Corn 2007. Pond-breeding amphibians are con sidered to be fire adapted and may benefit from fire maintaining breeding habitat (Pilliod et al. 2003). ...
... Hardy (2003) reported no differences in amphibian or reptile species richness or abundance between dormant-and growing-season burns at ephemeral ponds within an upland sandhills matrix. Schurbon and Fauth (2003) reported that prescribed burns decreased amphibian species richness at temporary ponds for two years, primarily because salamanders (including several Ambystoma spp. that did not occur at our study ponds) rarely used recently burned sites. In contrast, Langford et al. (2007) reported a greater abundance of herpetofauna in recently burned Mississippi pine savanna, but no difference in species diversity between burned and unburned uplands. ...
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We investigated how herpetofauna respond to burning and burn season in longleaf pine (Pinus palustris Mill.) sandhills by contrasting preburn species richness, diversity, and evenness and captures of six reptile and six amphibian species to the first (Y+1) or second (Y+2) year after burn or between dormant-season burns (DSB) and growing-season burns (GSB). Responses to burning overall or burn season were inconsistent among species; several showed no response, whereas others responded positively or negatively. Most responses were evident only in Y+1. Reptile species richness, diversity, and evenness responses were not detected. Amphibian richness increased after burning overall; diversity and evenness decreased more in GSB than in DSB in Y+1. Southern toad (Anaxyrus terrestris (Bonnaterre, 1789)) captures increased and Florida crowned snake (Tantilla relicta Telford, 1966) captures decreased following burns overall in Y+1. Ground skink (Scincella lateralis (Say in James, 1823)) captures increased more in DSB than GSB in Y+1. Florida gopher frog (Lithobates capito (LeConte, 1855)) and southeastern five-lined skink (Plestiodon inexpectatus; Taylor, 1932) captures increased, and oak toad (Anaxyrus quercicus (Holbrook, 1840)) decreased more in GSB than DSB in Y+2. Responses were likely due to changes in aboveground activity affecting captures or (for amphibians especially) annual variability in captures unrelated to burns. Our results indicated that reptiles and amphibians of sandhills are resilient to short-term effects of burning overall and burn season.
... The Florida Comprehensive Wildlife Conservation Strategy ranked "incompatible fire" as one of the highest overall threats across all Florida's terrestrial habitat (FWC 2005). Most land managers recognize the necessity of fire to maintain the longleaf pine ecosystem, but there is debate regarding the importance of fire season versus fire frequency (Bishop and Haas 2005) and as to the appropriate fire frequency (Schurbon and Fauth 2003, Robertson and Ostertag 2004. Additionally, many managers have to contend with managing units or entire properties that have heavy fuel loads resulting from long-term fire suppression. ...
... The Florida Comprehensive Wildlife Conservation Strategy ranked "incompatible fire" as one of the highest overall threats across all Florida's terrestrial habitat (FWC 2005). Most land managers recognize the necessity of fire to maintain the longleaf pine ecosystem, but there is debate regarding the importance of fire season versus fire frequency (Bishop and Haas 2005) and as to the appropriate fire frequency (Schurbon and Fauth 2003, Robertson and Ostertag 2004. Additionally, many managers have to contend with managing units or entire properties that have heavy fuel loads resulting from long-term fire suppression. ...
... The Florida Comprehensive Wildlife Conservation Strategy ranked "incompatible fire" as one of the highest overall threats across all Florida's terrestrial habitat (FWC 2005). Most land managers recognize the necessity of fire to maintain the longleaf pine ecosystem, but there is debate regarding the importance of fire season versus fire frequency (Bishop and Haas 2005) and as to the appropriate fire frequency (Schurbon and Fauth 2003, Robertson and Ostertag 2004. Additionally, many managers have to contend with managing units or entire properties that have heavy fuel loads resulting from long-term fire suppression. ...
... The Florida Comprehensive Wildlife Conservation Strategy ranked "incompatible fire" as one of the highest overall threats across all Florida's terrestrial habitat (FWC 2005). Most land managers recognize the necessity of fire to maintain the longleaf pine ecosystem, but there is debate regarding the importance of fire season versus fire frequency (Bishop and Haas 2005) and as to the appropriate fire frequency (Schurbon and Fauth 2003, Robertson and Ostertag 2004. Additionally, many managers have to contend with managing units or entire properties that have heavy fuel loads resulting from long-term fire suppression. ...
... The Florida Comprehensive Wildlife Conservation Strategy ranked "incompatible fire" as one of the highest overall threats across all Florida's terrestrial habitat (FWC 2005). Most land managers recognize the necessity of fire to maintain the longleaf pine ecosystem, but there is debate regarding the importance of fire season versus fire frequency (Bishop and Haas 2005) and as to the appropriate fire frequency (Schurbon and Fauth 2003, Robertson and Ostertag 2004. Additionally, many managers have to contend with managing units or entire properties that have heavy fuel loads resulting from long-term fire suppression. ...
... The Florida Comprehensive Wildlife Conservation Strategy ranked "incompatible fire" as one of the highest overall threats across all Florida's terrestrial habitat (FWC 2005). Most land managers recognize the necessity of fire to maintain the longleaf pine ecosystem, but there is debate regarding the importance of fire season versus fire frequency (Bishop and Haas 2005) and as to the appropriate fire frequency (Schurbon and Fauth 2003, Robertson and Ostertag 2004. Additionally, many managers have to contend with managing units or entire properties that have heavy fuel loads resulting from long-term fire suppression. ...
... The Florida Comprehensive Wildlife Conservation Strategy ranked "incompatible fire" as one of the highest overall threats across all Florida's terrestrial habitat (FWC 2005). Most land managers recognize the necessity of fire to maintain the longleaf pine ecosystem, but there is debate regarding the importance of fire season versus fire frequency (Bishop and Haas 2005) and as to the appropriate fire frequency ( Schurbon and Fauth 2003, Robertson and Ostertag 2004. Additionally, many managers have to contend with managing units or entire properties that have heavy fuel loads resulting from long-term fire suppression. ...
... Previous work has shown that the impacts of fire on amphibians can be variable across taxa and region (Grant et al., 1994;Greene et al., 2016;Hossack et al., 2009;Keyser et al., 2004;Langford et al., 2007;Schurbon and Fauth, 2003;Perry et al., 2012). The majority of studies have been in terrestrial systems, where fire has been found to increase adult movement or displacement due to microhabitat changes (e.g., O'Donnell et al., 2016). ...
Article
To effectively manage landscapes that support species with complex life cycles, managers should consider how current practices affect habitats these organisms rely on in each life stage. Prescribed fire is a landscape level disturbance that may alter both aquatic and terrestrial habitat characteristics. However, our knowledge of the effects of fire on amphibians is primarily limited to adult responses in terrestrial habitats. Here we present an integrated approach to test the response of Cope's Gray Treefrogs (Hyla chrysoscelis) to fire across terrestrial and aquatic habitats by examining responses in tadpole performance and survivorship, adult abundance, and oviposition choice. In a common garden experiment, tadpoles reared with unburned leaf litter grew much faster those in pools with burned litter. To determine how fire in terrestrial and aquatic habitats acts to shape oviposition choice, we embedded aquatic mesocosms containing a substrate of either burned or unburned leaf litter within burned and unburned terrestrial plots. Observed oviposition was an order of magnitude higher in unburned terrestrial plots, regardless of the aquatic leaf litter treatment. This trend was not driven by differences in adult abundance in burned and unburned plots. Our findings are consistent with a scenario where adult treefrogs use terrestrial cues to preferentially breed in aquatic sites in unburned landscapes where tadpoles also experience greater growth. These insights highlight the value of adopting a multi-scale integrative approach that links stage and habitat specific effects on abundance, behavior, and performance to understanding the effects of anthropogenic and natural stressors on animal with complex life cycles.
... Fire may change population dynamics of anurans both directly, by causing the death of individuals, and indirectly, through alteration of habitat (Gresswell 1999). Fire can significantly alter an environment by altering the humidity and temperature of the soil, the structure of the vegetation, the depth of the leaf litter, the rate of soil erosion and the hydroperiod of aquatic habitats (Cain et al. 1998, Schurbon & Fauth 2003. ...
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The rupestrian grasslands of the Serra do Espinhaço (Espinhaço Mountain Range) are mainly a savanna vegetation complex with a high degree of anuran endemism. Although this fire-prone vegetation is frequently burned by natural and anthropogenic fires, there is no information about how populations of the anurans of this ecosystem respond to such an impact. Aiming to evaluate the effect of fire on the anuran composition of a typical rupestrian grasslands environment, a high-elevation temporary pond of about 500 m² (Lagoa Seca) in Parque Estadual do Itacolomi was monitored during three different one-year time periods: Pre-fire (PrF), immediately Post-fire (PoF) and Seven Years Post-fire (7PoF). Surveys took place every two weeks throughout each study period. An increase in anuran species richness was found immediately after the fire event. The species present during the periods when the vegetation was in advanced stages of regeneration (PrF and 7PoF) were not eliminated by the fire event. Additionally, five species were recorded at low densities exclusively in the PoF period. The factors that may provide fire resistance to anuran of rupestrian grasslands and the implications of the results for fire management plans, a conservation measure previously treated as a taboo by many Brazilian conservation managers, are discussed.
... The current main cause of fire in the Cerrado is agriculture, set to transform native vegetation into crops or pastures (Coutinho 1990). Prescribed fires are hotter and may alter soil moisture and temperature, vegetation structure, litter thickness and erosion rates (Schurbon and Fauth 2003). Despite their ecophysiological constraints, the main effects of fire on amphibians are most likely indirect, as fire creates inhospitable environments associated with alterations to the leaf litter, ground cover and soil. ...
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The second largest biome in Brazil, the Cerrado has been transformed into a highly mechanized and intensive agricultural area, with little public opposition. The native anurofauna is rich in species number and endemisms, but has long been regarded as a generalist community originated from neighboring biomes. The accelerated degradation of Cerrado habitats caused by agriculture are bound to affect local anuran communities. This review aims to investigate the effects of anthropogenic activities on local amphibians. Despite a clear paucity, the existing studies indicate that, while this community may be more resilient to some anthropogenic activities (e.g. fire) than their forest counterparts, agricultural environments are strongly dominated by generalist species. Susceptibility to agro-cattle land-uses appears to be determined by specializations, especially regarding habitat and breeding strategies. Natural vegetation fragments are important for maintaining diverse anuran communities in agroecosystems. Agrochemicals cause histopathologic alterations and potential decreased fitness. Chytridiomycosis has been recorded in species extant in the biome, including endemics. The anurofauna appears to be especially sensitive to hydroelectric dams, as even previously common, widespread and generalist species declined or disappeared after dam flooding. Latest predictions indicate the occupation of the Cerrado will proceed northward, which, coupled with climate change, will cause great loss of biodiversity. Only a small portion of suitable natural habitats will remain in northern Cerrado, with amphibian richness being reduced to less than half. We conclude that less popular biomes may benefit from trait-oriented reviews to assess and guide future scientific and conservation projects.
... However, the use of fire in the mesic forested environments and the densely populated regions of the eastern United States has been limited, leading to potential "mesification," or a shift to less fire-adapted vegetation communities (Nowacki and Abrams 2008). Reintroduction of fire to these areas will require a well-planned approach, considering potential impacts on biota unique to the region (Schurbon and Fauth 2003), and using the power of geospatial tools and datasets to consider multiple stakeholder objectives in a landscape context (Driscoll et al. 2010). ...
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Many eastern forest communities depend on fire for regeneration or are enhanced by fire as a restoration practice. However, the use of prescribed fire in the mesic forested environments and the densely populated regions of the eastern United States has been limited. The objective of our research was to develop a science-based approach to prioritizing the use of prescribed fire in appropriate forest types in the eastern United States based on a set of desired management outcomes. Through a process of expert elicitation and data analysis, we assessed and integrated recent vegetation community mapping results along with other available spatial data layers into a spatial prioritization tool for prescribed fire planning at Shenandoah National Park (Virginia, USA). The integration of vegetation spatial data allowed for development of per-pixel priority rankings and exclusion areas enabling precise targeting of fire management activities on the ground, as well as a park-wide ranking of fire planning compartments. We demonstrate the use and evaluation of this approach through implementation and monitoring of a prescribed burn and show that progress is being made toward desired conditions. Integration of spatial data into the fire planning process has served as a collaborative tool for the implementation of prescribed fire projects, which assures projects will be planned in the most appropriate areas to meet objectives that are supported by current science.
... In addition to reducing coarse materials, fire may also reduce the amount of accumulated leaf litter. The loss of litter may cause amphibians to lose migration paths and be placed at greater risk of predation and desiccation (Schurbon and Fauth 2003). While fire may have negative short term effect on certain amphibian species, it can help maintain general habitat types for species living in glade and long-leaf pine communities (Brisson et al. 2003, Schurbon andFauth 2004) . ...
Technical Report
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In the tallgrass prairie region of North America, grasslands are often burned on a rotational schedule to prevent the encroachment of woody species and maintain the vigor of plant communities. Although prescribed fire practitioners often consider the effects of fire on plant communities, the effects of fire on wildlife are also important. Practitioners as well as park visitors inquire about the effects of fire on birds, deer, and other animals of interest. Many wildlife species focus on vegetation structure in choosing suitable habitats, and fire can temporarily alter that structure. Wildlife species have varying habitat needs, and therefore, a variety of responses to fire. To accommodate the variety of habitat needs for wildlife within grassland, fire can be implemented heterogeneously. For example, varying the time of year a burn occurs, and burning only portions of the habitat in a single year can help sustain populations. Monitoring programs aimed at quantifying populations and acceptable levels of mortality for species of interest may also help fire programs adapt to help wildlife populations thrive. This document provides information about the ability of birds, mammals, and herpetofauna to escape or survive fire. We also describe how fire induced changes to habitat can affect groups of animals and a suite of individual species.
... Les espèces arboricoles (rainettes) semblent sensibles à l'incendie de façon directe (forte mortalité), mais capables de reconstituer rapidement leur effectif, soit par recolonisation à partir de zones non brûlées, soit grâce à la survie in situ de quelques individus. L'effet des feux dirigés sur l'abondance et la diversité des amphibiens a été étudié aux Etats-Unis dans les zones forestières du sud de la Caroline (Schurbon & Fauth 2003). Cette étude porte sur 15 mares temporaires et 5 historiques post feu : 0, 1, 3, 5 et 12 ans après feu. ...
Technical Report
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Les incendies de forêts jouent en rôle clé dans les écosystèmes méditerranéens. Leur impact sur la biodiversité a fait l’objet de nombreuses études et de quelques synthèses récentes (Trabaud & Prodon 1993, Moreno & Oechel 1994, Valette 1999, Firetorch 2000, Ecologistes de l’Euzière 2004, EufireLab 2006). Toutefois, il n’existait pas jusqu’à ce jour de documents faisant un point détaillé sur ce thème. Le document présenté ici cherche à combler cette lacune. Il repose sur l’analyse de près de 320 publications consacrées pour tout ou partie aux incendies de forêts en région méditerranéenne. Pour réaliser cette synthèse, nous avons privilégié les études portant sur la région méditerranéenne, avec un accent particulier sur les travaux fait en France. Nous nous sommes donc focalisés sur les travaux réalisés dans les pays riverains de la Méditerranée. Cependant, lorsque certaines informations manquaient dans cette région, nous nous sommes tournés vers d’autres milieux à climat méditerranéen (notamment Californie, Afrique du sud et Australie). Par ailleurs, bien que nous ayons cherché à obtenir des documents sur les incendies « sauvages », nous n’avons pas négligé les travaux portant sur des opérations de brûlages dirigés, même si ceux-ci rendent compte de feux de moindre intensité et de moindre extension spatiale. Lors de nos recherches bibliographiques, il s’est vite posé le problème du nombre de publications existantes sur ce sujet, et de la difficulté à obtenir certains rapports ou documents peu diffusés. Compte tenu de cela, nous avons privilégié les documents les plus représentatifs et les plus importants dans le domaine. La plupart des documents collectés ont été utilisés dans le rapport qui suit, toutefois, le lecteur pourra se référer aux publications sources données dans la bibliographie et dans la base de données jointe. Cette base de données comporte, outre les indications habituelles à toute bibliographie, un résumé français précisant le contenu de la publication. Elle offre aussi différents modes de recherche : par date, par auteur mais aussi par mots clés, ce qui permet d’accéder rapidement aux thèmes recherchés.
... Still, habitat heterogeneity is considered a precursor for biodiversity (Baumberger et al., 2012;Simberloff, 1998) and the homogenous application of fire within the LLP ecosystem leads to a homogenous landscape (Lashley et al., 2014). There is growing evidence, including our findings, that variability in fire return intervals are important to maintaining diversity within the LLP ecosystem (Hiers et al., 2000(Hiers et al., , 2014Schurbon and Fauth, 2003). There is also increasing support for managing whole ecosystems instead of single species (Hallett et al., 2013;Jackson and Hobbs, 2009;Perring et al., 2015;Suding et al., 2015). ...
Article
A clear understanding of how management influences vertebrate biodiversity is critical for the conservation of rare ecosystems, such as the longleaf pine (Pinus palustris) ecosystem in the southeastern United States. We used scientific literature to assess how vertebrate use of the longleaf pine ecosystem (High or low) differed in response to high (1–3 years), moderate (>3–5 years), and low (>5 years) burn frequencies. For all species combined, we found that the number of high use (HU) species associated with moderately burned forests (n = 140) was 22% and 33% greater than in high (n = 115) and low burn (n = 105) frequency forests, respectively. This pattern was most clear for Aves and Reptilia. Specifically, the number of HU species associated with moderate burn frequencies (Aves – n = 69; Reptilia – n = 36) was 21% and 25% greater for Aves and 56 and 63% greater for Reptilia than high (Aves – n = 57; Reptilia – n = 23) and low burn frequencies (Aves – n = 55; Reptilia – n = 22), respectively. We found no difference in the number of HU species across burn frequencies for Amphibia or Mammalia. For species considered longleaf pine specialists, across all vertebrate taxa the number of HU species was associated with areas of high and moderate burn frequencies. We posit that moderate burn frequencies had the greatest number of HU species because of requirements for multiple habitat types, structural diversity, and habitat components that are reduced in, or not provided by, areas with high burn frequencies. If conservation of specific longleaf pine specialists that rely on habitat created by high fire frequencies (e.g. Red-cockaded woodpeckers) is the objective, we suggest managing with high burn frequencies at the local scale. Conversely, if management objectives include maximizing wildlife diversity, managers should use a more variable fire regime across the landscape, from annual to less frequent 5 year burn intervals, to maintain localized patches of oaks and increase the compositional and structural diversity within the system.
... We collected ectothermic aquatic vertebrates (i.e., amphibians, reptiles and fish; hereafter "vertebrates") in September 2006 using minnow traps placed in 16 random locations along the edge of each wetland (see Schurbon and Fauth, 2003). Traps were staked to the pond bottom in water 10-12 cm deep, which permitted airbreathing animals to breach the surface. ...
... However, our understanding of how best to manage the fire-return interval in forests with thinning and prescribed fire needs more attention (Means and others 2004;Pilliod and others 2003;Semlitsch 2000;Schurbon and Fauth 2004). Although many species appear minimally affected by fuel treatments (Ford and others 1999;Kirkland and others 1996;Litt and others 2001), some amphibian populations may experience shortterm negative effects (McLeod and Gates 1998;Schurbon and Fauth 2003). ...
Article
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This document is part of the Fuels Planning: Science Synthesis and Integration Project, a pilot project initiated by the USDA Forest Service to respond to the need for tools and information useful for planning site-specific fuel (vegetation) treatment projects. The information addresses fuel and forest conditions of the dry inland forests of the Western United States: those dominated by ponderosa pine, Douglas-fir, dry grand fir/white fir, and dry lodgepole pine potential vegetation types. Information was developed primarily for application at the stand level and is intended to be useful within this forest type regardless of ownership. Portions of the information also will be directly applicable to the pinyon pine/juniper potential vegetation types. Many of the concepts and tools developed by the project will be useful for planning fuel projects in other forest types. In particular, many of the social science findings would have direct applicability to fuel planning activity for forests throughout the United States. As is the case in the use of all models and information developed for specific purposes, our tools should be used with a full understanding of their limitations and applicability. The science team, although organized functionally, worked hard at integrating the approaches, analyses, and tools. It is the collective effort of the team members that provides the depth and understanding of the work.
... Fire is a major natural disturbance process which causes change to landscape structure in many ecosystems , Bond and Keeley 2005, Banks et al. 2011, Haslem et al. 2011) and has profound impacts on biodiversity (Veblen et al. 2000, Holmgren 2001. Substantial changes in species diversity and community structure may result from fire, including an increased risk of extinction for populations , Holmgren et al. 2001, Schurbon and Fauth 2003. Fires initiate temporal changes in the suitability of habitat for species , which may lead to patchily distributed populations with consequences for population demography (Brooker 1998, Banks et al. 2011, Sanz-Aguilar et al. 2011, genetic structure , Stow et al. 2007, Schrey et al. 2010, Spear and Storfer 2010 and metapopulation dynamics (Ellner and Fussmann 2003, Kallimanis et al. 2005, Vuilleumier et al. 2007). ...
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Anthropogenic fire is a worldwide event that affects many ecosystems and organisms. In Southern Brazil, grassland management with fire has been highly employed since the mid-18th century. Although the practice is regulated by federal law (prescribed fire), there is no detailed information about the impacts of this practice on the small, non-volant fauna. We evaluated the effect of fire management on anuran species richness and community composition in Brazilian grassland areas that have adopted this practice for more than 15 years. Our results show that burning practices lead to a reduction of anuran richness. About 37% of the species occur exclusively in sites free of fire. Sites with fire management have low densities of taller grass and shrubs, which could reduce habitat availability for some anuran species. Nestedness and turnover components of beta diversity did not differ within and between treatments, but there was a tendency for a nestedness organization of the community in burned sites, suggesting that sites with fire management are a subsample of sites where fire is absent. Our results pointed out that prescribed fire practices have potentially negative effects on the anuran diversity. These results suggest that the changes in vegetation, in particular percentages of shrub cover, affect habitat suitability for some species. As a consequence, anuran communities tend to become less diverse and lack arboreal species where fire occurs.
Article
Prescribed fire is a critical forest management tool, the frequency and size of which can alter the composition of wildlife communities. In the longleaf pine ecosystem of the southeastern United States, frequent prescribed fire (1–3 year fire interval) is used to replicate natural processes that prevent woody encroachment and transition to alternate states. However, we have little understanding of how different scales and frequencies of fire influence medium and large mammals. To address this knowledge gap, we assessed the homogenizing influence of prescribed fire on mammal community composition at different fire frequencies and scales. We set 110 camera trap grids containing 990 individual camera points across conservation lands in north Florida and the Florida panhandle. We used a Bayesian multi-species occupancy modeling approach to assess the relationship between fire frequency and the occurrence of 11 mammal species across three spatial scales (0.2 ha, 12.57 ha, and 176.71 ha). Species richness was negatively associated with increased burn frequency at all scales and community occurrence was negatively associated with increased burn frequency at the two largest scales. Non-native nine-banded armadillos were negatively associated with increased burn frequency at all scales and non-native feral hogs were negatively associated with increased burn frequency at the two largest scales. Raccoons and opossums, both known nest predators, were negatively associated with increased burn frequency at the two largest scales. Our results indicate that prescribed fire applied at 1–3 year intervals could be used to reduce the occurrence of most non-native mammals and several prolific nest predators in longleaf pine sandhills, particularly at larger scales. However, these perceived benefits must be weighed against the concurrent loss of the ecosystem services and functions native generalist species provide.
Article
Fire is a powerful environmental disturbance with the ability to shape many biomes worldwide. However, global warming, land-use changes and other anthropogenic factors have strongly altered natural fire regimes worldwide. Despite the growing number of studies evaluating the effects of fire on biodiversity, little is understood about how burn affects certain groups that are particularly sensitive to climatic extremes, such as anurans. Here, we conducted a global and systematic literature review of studies assessing anurofauna responses to fire disturbances. We used Generalized Linear Mixed-Effects Models and theoretical information criteria to assess how fire affects anuran assemblages. We analyzed 68 studies, widely distributed in the globe, which examined the fire effects on abundance, richness and/or species behavior. In total, 191 species were considered, being Gastrophryne carolinensis and Lithobates catesbeianus the most evaluated. We reveal a lack of general anurofauna response to fire, as species and assemblages were either negatively or positively affected by burns. We observed that the fire treatments (Prescribed fire, Wildfire and without fire) and the biome where the study was conducted did not explain the variation in species abundance. Most studies were conducted in biomes classified as Temperate Forests, followed by Tropical Savannas and Tropical Forests. We highlight that future studies should consider factors associated to fire (e.g. fire treatment, fire properties), research design and species biology to explain patterns of species persistence and community structure. Although fire plays a key role in shaping several natural ecosystems, we have recently witnessed drastic changes in natural burning regimes all over the world, which imply leading to severe population reductions and even species extinctions. Given this scenario, government authorities should urgently support and invest in scientific studies that evaluate, monitor and test fire management practices in natural ecosystems and therefore establish mitigation actions to preserve the biota constantly threatened by the imbalance of this environmental disturbance.
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Amphibians on African mountains are threatened by habitat loss and fragmentation, pollution, disease and climate change. In particular, there have been recent reports of declines of montane endemic frogs in Cameroon. Mount Bamboutos, although home to numerous species of endemic amphibians, has no official protection and its amphibian populations have so far not been studied quantitatively. We surveyed frog assemblages on this mountain along a gradient of forest modification over a -year period. Through visual encounter surveys stratified across forest and farmland , we found that threatened montane amphibian species are closely associated with forested areas, particularly the Critically Endangered Leptodactylodon axillaris and Endangered Leptodactylodon perreti, Astylosternus ranoides and Cardioglossa oreas. Using the updated inventory of amphibians, which includes species with broader ranges across Africa, we found % of amphibian species on Mount Bamboutos to be threatened. We did not record several species present in historical records, which suggests they may have disappeared from this mountain, including Cardioglossa pulchra, Phrynobatrachus steindachneri, Phrynobatrachus werneri, Sclerophrys villiersi, Werneria bambutensis and Wolterstorffina mirei. The pattern of change detected in the amphibian community is consistent with declines on other mountains in the country, with a loss of Phrynobatrachus, Werneria and Cardioglossa spp., but persistence of Astylosternus, Arthroleptis and Leptodact-y-lodon. The observed relationships of land-use patterns and amphibian diversity suggest that ongoing land-use changes could extirpate the remaining montane endem-ic frog species, particularly L. axillaris and L. perreti. Preserving a network of connected forest patches is therefore critical to save the endemic amphibians of Mount Bamboutos.
Article
Wildfire is an important natural disturbance event that promotes landscape heterogeneity and regulates many wildlife communities. The compounding effects of fire suppression and climate change have increased the frequency and severity of wildfire, but the responses of many organisms to wildfire is unknown. Landscape heterogeneity, specifically microhabitats, may mediate and buffer the effects of wildfire, and evaluating variable responses to wildfire given habitat is key to developing a more cohesive understanding of population responses. Terrestrial plethodontid salamanders are likely disproportionality affected by wildfire events because of their lungless anatomy and reliance on cool and moist habitats. Our knowledge of salamander responses to wildfire in the short-term is limited due to the inherent challenge of opportunistically studying post-wildfire events. We capitalized on a wildfire event in western North Carolina, USA to determine the short-term (6–18-month post-fire) habitat-mediated responses of salamanders to wildfire using body size measurement and repeated count surveys. We observed precipitous declines of the red-legged salamander, Plethodon shermani, in exposed upland forests, but no apparent negative effects in riparian forests 18-months post-fire relative to unburned sites. We also observed a loss of juvenile size classes in the upland burned forest with only the largest adult individuals remaining 18-months post-fire. There were no size class differences in the riparian forests. Our results suggest riparian forests may be buffered from the effects of wildfire because canopy cover, vegetation, and soil duff layer are retained following a wildfire event. Salamander populations inhabiting riparian forests may be at less risk of declining than those in exposed habitats. Our results underscore the need to assess wildfire effects in all habitat types to fully determine the effects of disturbance to populations.
Article
Frequent prescribed burns are essential to pine forest restoration and management. Research studies have assessed effects of prescribed fire and burn frequency on plants and vertebrates, but impacts of fire on terrestrial invertebrate communities are still poorly understood. This case study investigated effects of burning frequency on species richness and community composition of social insects (ants, Hymenoptera: Formicidae and termites, Blattodea: Isoptera) in fire-managed Southern longleaf pine flatwoods in central Florida. Community response to different fire frequencies was assessed: burned annually, every 2 yr, or every 3 yr, 30 yr unburned and 75 yr unburned. Richness was similar across all treatments, but ant community composition and species density significantly differed between frequently burned (1, 2, and 3 yr) and long-unburned (30 and 75 yr) treatments. Long-unburned treatments had higher ant abundance, but the species present were less characteristic of open canopy longleaf pine habitat than ants in frequently burned treatments. The annual burn treatment differed from 2-yr burn in species density, but to a lesser degree. Exotic species abundance was highest in frequently burned sites; only native species were detected in the 75-yr unburned plot. The red imported fire ant, Solenopsis invicta Buren (Hymenoptera: Formicidae), was detected in all regularly burned plots but not in long-unburned sites. Frequent burning at this site increased habitat suitability for ant species adapted to the sunny, open canopy, and diverse niches characteristic of longleaf pine forest; however, regular fire disturbance also increased the likelihood of exotic ant species establishment.
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From 2004 to 2006, we used a variety of sampling techniques to survey the amphibians of Savannah National Wildlife Refuge (SNWR), a large protected area straddling the lower portions of the Savannah River on the border between South Carolina and Georgia. We documented 22 amphibian species--15 frogs and 7 salamanders--with a possible 23rd species present. Species richness was lower than what might be expected from amphibian field guides of species inhabiting the adjacent Coastal Plain, likely due to a lack of specialized habitats, such as temporary ponds and upland pine forest. Amphibians occupied a variety of habitats and appeared tolerant of the mildly acidic and low-oxygen conditions of many of the wetlands. Although additional species may be found at SNWR, this initial survey provides a historic baseline for monitoring amphibian populations as areas adjacent to the refuge are disturbed, the climate changes, and multi-use management objectives are implemented within refuge boundaries.
Article
Fire regimes influence natural populations of organisms in diverse ways, via direct effects on population dynamics as well as indirect effects on habitat and ecosystem processes. Although many amphibian species have evolved to persist in fire-dependent ecosystems, the effects of fire on the genetic diversity of amphibian populations remain relatively unexplored. We examined how different aspects of fire history relate to population genetic diversity and structure of an abundant anuran, Hyla femoralis, in a large, intact area of Florida scrub containing hundreds of seasonally inundated ponds. Specifically, we assessed overall population genetic structure and examined whether variation in time since fire, fire intensity, or historical fire frequency at breeding sites explained spatial variation in genetic diversity. Based on our sampling of 17 breeding aggregations within the 2,100-ha study area, neither recent nor frequent fire reduce genetic diversity or restrict connectivity among ponds for H. femoralis. Overall, mean effective population sizes were large (average range = 68 - 572). We detected a positive trend between effective population size (Ne) and average intensity of the most recent fire, with this factor explaining 42% of the variation in Ne. Our results contrast with previous studies that consistently demonstrate strong relationships between fire history and population genetic structure of scrub-associated lizard species, suggesting that H. femoralis is resilient to a wide range of fire regimes. More generally, our study contributes to understanding the roles of life-history characteristics and environmental unpredictability in shaping organisms' responses to fire.
Article
Aim To quantify how frogs in terrestrial environments respond to recurrent fire, and to what extent this is mediated by isolation from breeding sites or vegetation structure. Location Jervis Bay, south‐eastern Australia. Methods We used data from 8 years of pitfall trapping, collected via a random stratified design, to quantify frog occurrence at 110 locations. We then used an information theoretic approach to compare 13 logistic generalized linear mixed models, each of which related frog occurrence to a distinct combination of additive and interactive effects of fire, vegetation structure and proximity to known breeding sites. Results For all four species, the effect of one or more fire variables on frog occurrence depended on both the density of breeding sites in the surrounding area, or on the vegetation structure at the trap locality. A classic “fire averse” response of initial declines followed by post‐fire recovery did occur, but only in frequently burned, low‐quality terrestrial habitats (i.e., heath vegetation for Uperoleia tyleri, or locations with few available breeding sites for the remaining species), or in some cases, when suitable habitats were infrequently burned. However, a “fire‐dependent” result of negative effects of time since fire was also evident for some species and contexts. Main conclusions The effect of fire on frog occurrence can be mediated by environment. Therefore, a single species could be identified as either “fire dependent” or “fire averse” depending on the combination of isolation, vegetation types and fire histories in the study region. Failure to account for the context specificity of fire response curves could lead to incomplete conclusions regarding the effect of time since fire—or the cumulative impacts of multiple fires—on faunal assemblages.
Article
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Natural and anthropogenic disturbances co‐occur in most systems, but how they interact to shape demographic outcomes remains poorly understood. Such interactions may alter dynamics of populations in non‐additive ways, making demographic predictions challenging when focusing on only one disturbance. Thus, understanding the interactive effects of such disturbances is critically important to determine the population viability of most species under a diversity of stressors. We used a hierarchical integral projection model ( IPM ), parameterized with 13 years of field data across 20 populations, encompassing 2435 individuals of an endangered herb, Liatris ohlingerae . We examined interactive effects of vertebrate herbivory, fire and anthropogenic activities (sand roads) on vital rates (e.g. survival, growth, reproduction, recruitment) and ultimately on population growth rates (λ), to test the hypothesis that interactions amplify or dampen differences in λ depending on environmental contexts. We constructed megamatrices to determine coupled dynamics in individuals damaged vs. not damaged by herbivores in roadsides and in Florida scrub with different times since fire. We identified strong interactive effects of fire with herbivory and habitat with herbivory on vital rates and on population growth rates in the IPM model. We also found different patterns of variation in λ between habitat and time‐since‐fire scenarios; population growth rates were higher in roadside populations compared to scrub populations and declined with increasing time since fire. Herbivory had interactive effects with both fire and human disturbances on λ. Herbivory resulted in decreased differences in λ due to anthropogenic disturbance and slightly increased differences in λ due to time since fire. Synthesis . The co‐occurrence of various disturbances may both amplify and dampen the effects of other disturbances on population growth rate, thus shaping complex population dynamics that are neither linear nor additive. These realistic nonlinearities represent challenges in understanding and projecting of population dynamics. Here, we examined the effects of various sources of disturbance on the population dynamics of an endangered plant species, finding complex interactions affecting population growth rates. We argue that integration of multiple, interacting stressors in IPM s will allow more accurate estimation of the overall effects of ecological processes on species viability.
Article
I have analyzed presence, abundance, and patterns of coexistence of 11 species of pond-breeding salamanders from 203 managed sites in Indiana, Illinois, Kentucky, Michigan, and Ohio. Among these include 47 longterm sites that have been monitored for 7-15 years. The two most abundant species, Ambystoma tigrinum and A. texanum, use open habitats such as grasslands and savanna, and are found in single species communities significantly more often than expected by a null model. Several other species were more likely to coexist with certain species in assemblages, and communities of four or more species occurred significantly more often than predicted by null models. All of the sites with four or more species have fishless seasonal or semi-permanent wetlands and forested upland habitat. Among populations with long-term data, five species declined at some sites and two species increased at some sites, however, most population dynamics were apparently stable fluctuations. The declining species were primarily found in mature forest upland habitat and typically breed in fishless seasonal wetlands, whereas the increasing species use open upland habitats and semi-permanent to permanent wetlands. Regression and General Linear Models indicate that the timing of prescribed burns was a significant factor in determining the relative abundance of pond-breeding salamanderlarvae. Prescribed burns during spring had a negative affect on the relative abundance of nine of the 10 species that I examined; the exception was the obligate aquatic salamander Siren intermedia. The forest dwelling species took a mean of 4.6 years for populations of these species to recover to pre-burn levels. Prescribed burns also negatively affected Ambystoma tigrinum, A. texanum, and Notophthalmus viridescens, however, their mean time to recover was just 1.6 years and they typically exceeded pre-burn abundance. Conservation management practices should avoid using frequent springtime prescribed burning of wetlands and surrounding upland habitats when pond-breeding salamanders are present.
Article
From June to September 2011, we had chosen 3 group pure plantations of Cunninghamia lanceolata in different ages and 3 group mixed plantations of C. lanceolata and Pinus massoniana in varied ages as samples, investigated the plant communities, and used the method of "fence with pitfall trap" to investigate amphibian communities. The results showed that: 1) the effects of forest age on amphibian niche were higher than those of species composition of plantations, and the biodiversity rule of shrub and herbaceous layer was same with the rule of amphibian niche width. 2) Amphibians in the same family had a high degree of niche overlapping and the competition was fierce. 3) The adaptability of amphibians to forest age change of plantations was different with plants, and in mature and over-mature stands, the niche width of amphibians became narrow and the number declined.
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Fire can cause profound changes in the composition and abundance of plant and animal species, but logistics, unpredictability of weather, and inherent danger make it nearly impossible to study high-severity fire effects experimentally. We took advantage of a unique opportunity to use a before-after/control-impact (BACI) approach to analyze changes in bird assemblages after the severe fires of 2000 in the Bitterroot Valley, Montana. Observers surveyed birds using 10-minute point counts and collected vegetation data from 13 burned and 13 unburned transects for five years before fire and three years after fire. We compared changes in vegetation variables and relative bird abundance from before to after fire between the set of points that burned and the set of points that did not burn. The magnitude of change in vegetation variables from before to after fire increased with fire severity. The relative abundances of nine bird species showed significantly greater changes from before to after fire at burned points compared with unburned points. Moreover, when burned points were separated by whether they burned at low, moderate, or high severity, an additional 10 species showed significant changes in relative abundance from before to after fire at one or more severities. Overall, almost twice as many bird species increased as decreased significantly in response to fire. We also found changes in abundance between one year after and two years after fire for most species that responded to fire. Thus, species that have been termed "mixed responders" in the literature appear to be responding differently to different fire severities or different time periods since fire, rather than responding variably to the same fire conditions. These findings underscore the importance of fire severity and time since fire and imply that both factors must be considered to understand the complexities of fire effects on biological communities. Because different bird species responded positively to different fire severities, our results suggest a need to manage public lands for the maintenance of all kinds of fires, not just the low-severity, understory burns that dominate most discussions revolving around the use of fire in forest restoration.
Article
Fire is a frequent feature of African grasslands because agriculture is often used as a management tool in conservation areas. Richness, diversity, and abundance of amphibians were compared in four areas of montane grassland subjected to different fire regimes in Nyika National Park (Malawi, southeastern Africa). The surveys were performed using drift fences and pitfall traps randomly set in four areas (12 sites) subjected to the following fire regimes: (A) no fire for at least 15 years; (B) no fire for at least 10 years; (C) no fire for at least 6 years; and (D) annually burned. We also measured the vegetation cover and vegetation height. We collected 370 amphibians from 17 species and six families during 50 days sampling period. The lowest value of abundance was found in areas C and D. The amphibian species Hyperolius marmoratus and H. nasutus were most abundant in the control area A. Arthroleptis xenodactyloides, Amietophrynus gutturalis and Am. maculatus were found in all areas. There was a strong correlation between vegetation height and species richness. Vegetation structure, which is affected by fire, appears to be a key factor impacting amphibian assemblages in montane grasslands.
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This chapter describes a 16-year study, in which it has been found that pond hydroperiod is a primary source of variation in community structure for a natural community of pond-breeding amphibians. Larval competition and predation form other axes that are positioned along a continuum of hydroperiod, and the strength of their influence on the success of species is mediated by pond hydroperiod. Although hydroperiod, competition, and predation had a detectable influence on the amphibian community at Rainbow Bay, the effects of these factors were often difficult to separate. Correlative analyses are less powerful for sorting out confounding factors than manipulative experiments in replicated artificial ponds. The predictor variables used are often themselves correlated. Nevertheless, in many cases, a good year for a species is also a good year for its competitors and predators. Juvenile recruitment of all species is limited by a short hydroperiod in the driest years. In years with longer hydroperiods, the density of competitors affected the number of metamorphosing juveniles per breeding females for some species. The density of salamander larvae is also a significant predictor of per-capita juvenile recruitment for anurans. A significant negative relationship is detected for two of four anuran species analyzed, most likely due to predation by the salamander larvae on the anuran tadpoles. These results indicate that community structure, at least in terms of relative abundances, varied continuously. However, regulation of community structure within a pond occurs through the predictable interaction of rainfall, hydroperiod, competition, and predation.
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The largest known breeding migration of the flatwoods salamander (Ambystoma cingulatum) was monitored over a 22-year period following its discovery in 1970 in Liberty County, Florida (U.S.A.). Nightly migrations of 200–300 adults across a 4.3-km stretch of paved highway in 1970–1972 had dwindled to less than one individual per night in 1990–1992; the decline apparently was already underway in the 1980s. We discuss possible natural and anthropogenic causes of the decline. The silvicultural practice of converting native longleaf pine savanna to bedded slash pine plantation, implemented on our study site about 1968, may have interfered with migration, successful hatching, larval life, feeding, and finding suitable cover post-metamorphosis. Longleaf pine-wiregrass flatwoods inhabited by adults have been drastically reduced and severely degraded throughout the coastal plain and may explain why the species is rare and deserving of threatened status.
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A 1993 wildfire and subsequent landslides modified many streams in the Santa Monica Mountains of southern California (USA). Prior to the fire at Cold Creek Canyon, adult California newts (Taricha torosa) frequently preyed on conspecific eggs and larvae. Post-fire landslides increased the number of stream pools containing terrestrial earthworms. Earthworms were more common in adult newt diets after the fire, and con- specifics were absent. More earthworms and fewer conspecifics were present in the stomachs of adult newts in streams at burned sites than at unburned sites. In laboratory experiments, newt larvae used refuges significantly less in the presence of combined chemical cues from both newt adults and earthworms as compared to adult-newt cues alone. These data suggest that cannibalism is reduced in the presence of increased alternative prey items and that larvae can detect this reduced predation risk.
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To test a model of fish assemblage structure in isolated wetlands of the Atlantic Coastal Plain, we related the presence or absence of fishes in individual wetlands and variation in assemblage structure to environmental conditions within wetlands and to location in relation to permanent aquatic habitats. Fishes were limited to wetlands that dried infrequently, were relatively close to intermittent aquatic habitats, and had little elevation difference between the wetland and its nearest permanent aquatic habitat. Comparison of variation in assemblage structure among wetlands to null hypotheses of randomness suggested that biological interactions played a minor role in structuring these assemblages. We found no correlation between assemblage structure and wetland environment. Variation in assemblage structure was correlated with the geographic position of wetlands. Wetlands located in the upper portions of drainage basins were dominated by Lepomis marginatus and Erimyzon sucettawhile wetlands located in downstream portions of drainage basins were dominated by Acantharchus pomotisand Gambusia holbrooki. Our results are consistent with a model of fish assemblage structure in which wetland drying frequency and connectivity determine the presence or absence of fishes, and differences in colonizing rates and the relative abundance of species in source pools influence variation among wetlands with fishes.
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We determined the relative abundance, days of surface activity and indices of species diversity, evenness and richness for amphibians inhabiting three differently managed forests surrounding a Carolina bay in South Carolina following restoration. We collected animals daily for 3 y (Oct. 1993–Sept. 1996) using drift fences with pitfall traps in three forest types: loblolly pine (Pinus taeda), slash pine (P. elliotti) and mixed hardwoods (predominantly oak, Quercus spp. and hickory, Carya spp.). Captured animals were marked and recaptures were recorded but not included in statistical analyses, except in our evaluation of activity. We compared results to those of a more limited study conducted before restoration. Amphibians were significantly more numerous and more active in the mixed hardwood forest than in the pine forest types. However, the hardwood forest had the lowest species diversity in 2 of the 3 y of the study. The slash pine habitat had the highest diversity in all 3 y and for the 3 y combined. Because the evenness index (J′) values differ in step with the species diversity index (H′) it appears that the evenness component of diversity, rather than the richness component, is what is determining H′ variation. A summer subset of these data and summer data from an earlier study of 1977–1978 is in marked contrast with yearlong patterns. For our summer data each forest type had the highest H′ value in one of the years of the study and again the J′ values parallel the differences in H′. Large numbers of southern toads (Bufo terrestris) reduced evenness, and therefore species diversity, for all three habitats particularly the mixed hardwoods where this species was especially abundant. Proportionally lower numbers of B. terrestris in the summer samples increased J′ and H′ indices. Overall lower abundance and H′ values in the summers of 1994–1996 compared with 1977–1978 may be the result of habitat alteration during the restoration of the Carolina bay.
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Fire and insects are natural disturbance agents in many forest ecosystems, often interacting to affect succession, nutrient cycling, and forest species composition. We review literature pertaining to effects of fire-insect interactions on ecological succession, use of prescribed fire for insect pest control, and effects of fire on insect diversity from northern and boreal forests in North America. Fire suppression policies implemented in the early 1900s have resulted in profound changes in forest species composition and structure. Associated with these changes was an increased vulnerability of forest stands to damage during outbreaks of defoliating insects. Information about the roles that both fire and insects play in many northern forests is needed to increase our understanding of the ecology of these systems and to develop sound management policies.
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Although there is growing concern that amphibian populations are declining globally1±3, much of the supporting evidence is either anecdotal4,5 or derived from short-term studies at small geographical scales6±8. This raises questions not only about the dificulty of detecting temporal trends in populations which are notoriously variable9,10, but also about the validity of inferring global trends from local or regional studies11,12. Here we use data from 936 populations to assess large-scale temporal and spatial variations in amphibian population trends. On a global scale, our results indicate relatively rapid declines from the late 1950s/early 1960s to the late 1960s, followed by a reduced rate of decline to the present. Amphibian population trends during the 1960s were negative in western Europe (including the United Kingdom) and North America, but only the latter populations showed declines from the 1970s to the late 1990s. These results suggest that while large-scale trends show considerable geographical and temporal variability, amphibian populations are in fact declining-and that this decline has been happening for several decades.
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Experimental plots were burned every year (1E), every 2yr (2E), or every 7yr (7E); the control plot (CE) has not burned for 20yr. Amphibians and reptiles of 27 species were captured. Severe cold in December 1983 may have caused a large decline in herpetofauna in 1984. Both Shannon-Weiner and Simpson's diversity indexes indicated that plot 2E had the lowest diversity each year. Greatest diversity was found on 1E or 7E. The 2yr fire periodicity produced a dense layer of grasses and herbaceous plants that was not readily occupied by sandhill herpetofauna. The most abundant reptile was 6-lined racerunner Cnemidophorus sexlineatus (33% of all captures). The highest density of racerunners was found on 1E, while lizards on 7E showed the greatest philopatric tendencies (especially in 1983, the year 7E was burned). -from Author
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The impact of fire on small mammals and amphibians was investigated in an oak (Quercus spp.)-dominated forest in S-central Pennsylvania. Sampling with Y-shaped arrays of pitfalls and drift fences was conducted for 78 days between 31 March and 13 November 1992 following a fire in November 1991. Shrews, rodents and total small mammals were significantly less abundant in burned than in unburned forest; however, significant differences between habitats were recorded only for the 1st 3 sampling periods (April, June, July) for rodents and total small mammals. Eight species of small mammals were captured in unburned forest compared to six species in burned areas. The two species not taken in the burned forest were both arvicoline rodents, the meadow vole (Microtus pennsylvanicus) and southern red-backed vole (Clethrionomys gapperi). A significant correlation was found between the rank order of species of small mammals taken in burned and unburned habitats. The two most abundant species in both habitats were the white-footed mouse (Peromyscus leucopus) and Maryland shrew (Sorex fontinalis), which combined comprised 78.1% of the small mammals taken in the unburned forest and 72.4% of the sample from the burned site. In contrast to small mammals, significantly more amphibians were captured in the burned forest. The American toad (Bufo americanus) was the most abundant amphibian, comprising 70.8% of the amphibians captured; this species was largely responsible for the greater numbers of amphibians captured in the burned forest.
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Censuses of forest floor amphibian assemblages at 17 sites in New York revealed that amphibian density and species richness were lower in more acidic habitats. At least three species of salamanders have field distributions that suggest an avoidance of acidic conditions. A gradient of humus and mineral soil pH exists with relatively high [H+]s in the forest interior and lower [H+]s near streams and seepage areas. Small scale maps of humus and mineral soil [H+] reveal much spatial heterogeneity in a beech forest and little in coniferous forests. High concentrations of aluminum and/or iron, in soil solutions at low pHs, reduce sodium available for uptake by amphibians, and together with increased sodium efflux on low pH substrates probably result in a toxic disruption of sodium balance. -from Authors
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Embryonic mortality of the salamander Ambystoma jeffersonianum was high in those C Pennsylvanian ponds studied below pH 4.5. Less pH-associated embryonic mortality was observed among the more tolerant salamander, Ambystoma maculatum and frog Rana sylvatica. Laboratory-determined LC50 values for hatching of R. sylvatica, A. maculatum and A. jeffersonianum were 4.10, 4.31, and 4.51, respectively. More larval R. sylvatica survived at pH 4.1 in the laboratory when initially contained with A. jeffersonianum than at pH >6, due to reduced survival of, and subsequent reduced predation by, A. jeffersonianum at pH 4.1. Survival of A. maculatum was not different between pHs as they were eaten by A. jeffersonianum at pH >6 and suffered pH-induced mortality at pH 4.1. More larval A. jeffersonianum survived at pH 4.1 over 7 days when larval R. sylvatica and A. maculatum were available as prey, than when no prey were available. Larval A. jeffersonianum did not survive to metamorphosis in pH 4.2, and survived in low numbers in pH >6. Ambystoma maculatum metamorphosed less often, took longer to metamorphose, and weighed less at metamorphosis in simulated ponds of pH 4.2 versus those of pH >6. Reproduction of the newt Notophthalmus viridescens was significantly lower, and adults were trapped more often exiting ponds, in pH 4.2 than in pH >6. Presence of adult N. viridescens resulted in significantly lower survival of R. sylvatica at metamorphosis; survival was not significantly affected by pH 4.2. -from Authors
Article
The effect of low environmental pH on amphibians was studied in central Pennsylvania and the New Jersey Pine Barrens. Jefferson salamander (Ambystoma jeffersonianum) and Fowler's toad (Bufo woodhousei) embryos were intolerant of low pH and were absent from the most acidic ponds. Wood frog (Rana sylvatica) and pine barrens treefrog (Hyla andersoni) embryos were tolerant and found in ponds with the lowest pH's. Laboratory tests demonstrated that A. jeffersonianum could not hatch below pH 4.50, whereas R. sylvatica could hatch even at pH 4.25. Similarly, B. woodhousei could not hatch below pH 4.10, but H. andersoni could hatch at pH 3.70. Embryos of all four species were transplanted into several ponds ranging in pH from 3.90-7.06 to test whether embryonic mortality caused by low pH could be responsible for the absence of the two least tolerant species from acidic ponds. Hatching of embryos of R. sylvatica was not related to pond pH while mortality of embryos of A. jeffersonianum increased significantly as pond pH declined. H. andersoni also hatched in all experimental New Jersey ponds, but embryos of B. woodhousei suffered significantly higher mortality in ponds of lower pH's. Hatching success was variable at specific pond pH's, indicating significant interaction of pH with other chemical variables. In laboratory trials, tadpoles of B. woodhousei and H. andersoni grew significantly slower when exposed to low pH. This sublethal effect on body size has important implications for dynamics of amphibian populations in acidic ponds.
Article
From 1975-86, 1831 meter square quadrats of forest litter in five study sites in southcentral New York were searched for the presence of amphibians. Soil moisture and pH were also determined. Sixteen species of forest amphibians representing 10 species of Caudata and six species of Anura were found. The distributions of Bufo americanus, Plethodon cinereus, Eurycea bislineata, Desmognathus fuscus and Ambystoma maculatum were significantly influenced by soil pH. Soil moisture also influenced species distributions. Rana sylvatica, E. bislineata, D. fuscus, Notophthalmus viridescens and A. maculatum occurred on quadrats with a significantly higher average moisture content than quadrats without amphibians. Both soil moisture and soil pH should be determined when factors influencing amphibian distributions are being examined. Soil pH in the eastern United States is within the range that can be lethal to some species and inhibits the growth of others. More information is needed to assess the long term consequences of soil acidification on amphibian populations.
Article
Identifying keystone species is essential for understanding community dynamics and preserving species richness. However, few studies have used quantitative, a priori methods to identify potential keystone species. Species known to act as keystones in North Carolina (NC) temporary ponds (Notophthalmus viridescens, eastern newt, and Siren intermedia, lesser siren) were tested to see whether they played the same role in similar habitats in South Carolina (SC). Newts and sirens had no effect on anuran species richness in SC. Instead, another salamander (Ambystoma talpoideum, mole salamander) absent from the NC ponds was identified as a strong keystone in SC. It functioned independently of environmental factors and the densities of other predators. Larval dragonflies (Tramea carolina, Carolina saddlebag) were identified as weak, context-dependent keystones in SC, supporting anuran richness in isolated ponds with very low pH. The results suggest that the identity of keystone species varies, even in similar habitats within a physiographic region.
Article
This study examines direct and indirect interactions that influence the distribution of larvae of the bullfrog (Rana catesbeiana) and green frog (R. clamitans) along the environmental gradient of permanent to temporary ponds. The bullfrog is found in permanent ponds that typically contain fish, whereas the green frog is widely distributed along the gradient and is most successful in ponds where the bullfrog is absent. In a set of experimental ponds, bullfrogs were most abundant in ponds containing fish (bluegill, Lepomis macrochirus) and were rare in permanent ponds that lacked fish. In contrast, green frogs were most abundant in ponds that had been drained the previous fall, second most abundant in those that lacked fish, and sparse in ponds containing bluegill. When presence and absence of bluegill were experimentally manipulated in divided ponds, bullfrogs survived well in the presence of bluegill, whereas no individuals survived in the absence of bluegill. Green frogs survived in low numbers under both treatments with a tendency to better survivorship in the absence of bluegill. A series of laboratory choice experiments was conducted with three major predator types: the dragonfly larva Anax junius, the salamander Ambystoma tigrinum, and L. macrochirus. Bullfrog larvae were more vulnerable to Anax and Ambystoma than were green frogs (because of higher activity levels), and green frogs were more vulnerable to bluegill than were bullfrogs (because tadpoles were less noxious). We argue that the high densities of bullfrogs found in the presence of bluegill reflect an indirect facilitation through two pathways: bluegill had strong negative effects on invertebrate and salamander predators of bullfrogs and on the green frog, which is a bullfrog competitor. The direct and indirect effects of these suites of predators appear to explain the differences in species abundances along the environmental gradient. Finally, we discuss the trade-offs at the individual level contributing to these differences in species performance along the gradient.
Article
Censuses at two sites in Delaware County, New York from spring 1981 through spring 1985 indicated that the density and distribution of Plethodon cinereus were influenced by soil pH but not by soil temperature or moisture. Of 1044 1-m² quadrats of forest litter searched, 284 had a pH of 3.7 or less and only 25 of these (8.8%) contained salamanders. Of 760 quadrats with a pH 3.8 or more, 386 (50.8%) contained salamanders. Juvenile salamanders were never found on soils with a pH less than or equal to 3.7. Seasonal salamander density was correlated (r = -0.92) with the percentage of quadrats with a pH of 3.7 and less. Salamanders apparently were excluded from 27% of forest habitat because of low soil pH. In the laboratory, P. cinereus preferred to occupy substrates near neutral pH when given a choice among three levels of substrate acidity. The acutely lethal pH was between 2.5 and 3 and the 8-mo chronically lethal pH was between 3 and 4. Growth and respiration were reduced at low pHs. The influence of soil pH on salamander distribution might fundamentally change the forest floor decomposer food web of which P. cinereus is an upper-level consumer.
Article
Identifying the factors that limit species distributions and maintain patterns of diversity is a major goal of temporary pond ecologists, and an important pursuit for conservation biologists. We used multiple regression analysis to identify ecological correlates of anuran species richness in twenty-one temporary pools within the Francis Marion National Forest, South Carolina. Analysis of data collected in 1996–1997 revealed that anuran richness was limited by the multiplicative effects of pool acidity, hydroperiod, and fish species richness. Anuran species richness declined with decreasing pH and hydroperiod, and with colonization by more species-rich assemblages of predatory fish. Two species of frog (Hyla cinerea and Rana grylio) and a newt (Notophthalmus viridescens) were excluded from the most acidic pools, and three anurans (Bufo quercicus, Pseudacris ornata, and R. capito) were limited by fish. Two large-bodied frogs with tadpoles that overwinter prior to metamorphosis (R. catesbeiana and R. virgatipes) were restricted to pools with longer hydroperiods, and R. capito was more likely to breed in large than in small ponds. The results suggest that anuran richness at our study site is controlled by different factors than in similar ponds in North Carolina, where hydroperiod and the densities of tadpoles and two species of salamander were important. Identifying mechanisms likely to affect local anuran species richness allowed us to predict how subtle anthropogenic stresses could cause declines in amphibians to begin, in a region where few have been reported.
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This manual details standard field methods for qualitative and quantitative sampling of amphibian biological diversity. An introductory chapter is followed by an overview of amphibian diversity and natural history. Essentials of standardization and quantification are then covered. Next research design for quantitative amphibian studies is outlined. Chapter five looks at project planning and data acquisition and handling. Chapter six covers standard techniques for inventory and monitoring. Supplementary approaches are examined in the next chapter: artifical habitats; acoustic monitoring; tracking; night driving; GIS; and group activities/field trips. The ninth chapter looks at mark-recapture and removal sampling as methods of population estimation, followed by a chapter on data analysis. A conclusions and recommendations chapter is followed by seven appendices: handling live amphibians; techniques for marking amphibians; recording frog calls; specimen preparation; collecting tissue for biochemical analysis; vendors; and random number table. -S.R.Harris
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Banksia woodland is a seasonally arid and fire-prone environment. Although a seemingly inhospitable environment for frogs, seven species were recorded in pitfall-trapping carried out in six areas of Banksia woodland near Perth from April 1983 to March 1986. These areas had different fire histories, ranging from recently burnt to unburnt for 23 years. One of the areas was burnt during the course of the study. Three species made up 95% of captures, viz. Heleioporus eyrei, Limnodynastes dorsalis and Myobatrachus gouldii. Annual numbers of captures of H. eyrei were not greatly affected by fire or increasing time after fire. L. dorsalis and, to a lesser extent, M. gouldii were caught in greater numbers in long-unburnt areas than in recently burnt areas. Variation in the abundance of L. dorsalis and M. gouldii with time after fire did not appear to be related to changes in leaf litter and vegetation density, or to the abundance of invertebrates as potential prey.
Article
The distribution and abundance of amphibians and reptiles in forest stands subjected to salvage cutting and prescribed burning were compared with their unmanaged counterparts. The study was conducted on the Atlantic coastal plain at Chesapeake Farms near Chestertown, Maryland. Three herpotofaunal trapping arrays were systematically located in each of four forest stand types: hardwood (Hardwood), cut-over hardwood (Cut), mixed pine-hardwood (Pine) and prescribed burn pine (Burn). A total of 3931 individuals representing 29 species were captured in 30,540 trap nights during the spring and summer 1992 and 1993. Feeling of hardwoods and prescribed burning of pine resulted in similar responses from the herpetofaunal communities; Hardwood had the most distinctive herpetofaunal community of the four stands. Adults and young-of-the-year (YOY) of six amphibian species were significantly more abundant in Hardwood than Cut. Only one amphibian species, Pseudacris triseriata, was less abundant in Hardwood than Cut. Total ranid captures did not differ between Hardwood and Cut. Snake and total reptile captures, and Elaphe obsoleta and Eumeces faciatus abundances were significantly less in Hardwood than Cut. Hardwood also had fewer small mammals than Cut, particularly Microtus pennsylvanicus and Zapus hadsonius, that might serve as prey for large snakes. Adults of four amphibian species, YOY of five amphibian species, and three reptiles (Carphophis amoenus, Storeria dekayi and Thamnophis sirtalis) were significantly more abundant in Pine than Burn; two reptile species (Coluber constrictor and Lampropeltis getula) were significantly less abundant. Potential small mammal prey of the latter two snakes were not significantly different between Pine an Burn; however, Zapus hudsonius was less abundant in Pine than in Burn. More amphibians were captured in Hardwood and Pine stands than in their respective logged and burned counterparts. The trend for reptiles tended to depend on the mix of species present and their habitat preferences. Greater canopy cover and depth of leaf litter in Hardwood and Pine stands likely had a moderating effect on temperature and helped to maintain a moist microenvironment for mesophilic species. Disturbance of a small patch of forest could locally decreased herpetofaunal diversity, but diversity on a much larger scale would likely increase.
Article
Larvae of 15 amphibian species were tested for 2 key defenses: unpalatability and chemically mediated predator avoidance. In 8 of 9 cases, larvae of species that often encounter fish had at least one of these defenses. Larvae of 7 species that breed in fishless pools consistently lacked defenses against fish. Lack of appropriate defenses appears to be a primary reason why temporary pool species cannot successfully coexist with predatory fishes in permanent habitats. Palatability and responses to chemical cues from fish often differed among closely related taxa and were correlated strongly with frequency of encounter with fish. Thus, natural selection rather than phylogeny best explains interspecific variation in antipredator defenses. Members of at least 2 orders and 4 families of amphibians use chemical cues to reduce predation risk from predatory fish. -from Authors
Article
Diversity indices and relative abundances were determined for amphibians inhabiting three differently managed forest types in South Carolina. Study sites were contiguous around a small lake, and included a slash pine (Pinus ellioti) forest, a loblolly pine (Pinus taeda) forest and a hardwood (predominately oak-hickory) forest. Amphibians were collected using a drift fence and pitfall trap method. Captured animals were marked so that recaptures could be removed from calculations of indices. The dates of study were 30 June-10 August 1977 and 20 June-15 August 1978. The three study sites were similar in species diversity and the evenness component for combined summer data and for the summer of 1978. The hardwood forest had a higher diversity in the summer of 1977. The hardwood forest yielded approximately 50% more individual amphibians than either pine forest during both years.
Article
Green tree frog (Hyla cinerea) tadpoles were exposed immediately after hatching to aluminum (nominally 0, 150, 250, 400 mu g/L) at pH 4.5 or 5.5, plus a control (pH 7.0, 0 mu g/L Al) for 96 h. Mortality increased with increasing Al concentration at pH 4.5 but not at pH 5.5. Among surviving tadpoles, body size was significantly reduced at higher Al concentrations at both pH 4.5 and 5.5. At pH 4.5, analysis of covariance indicated that maximal swimming speed was positively correlated with tadpole total length and differed among Al treatments; tadpoles at higher Al levels swam more slowly. Body Al and Na+ concentrations also differed among treatments. In a second experiment, tadpoles exposed for 96 h to approximately 150 mu g/L Al at 4.5 pH were preyed upon by dragonfly larvae (Libellulidae) at a higher rate than were tadpoles raised in pH 4.5 or 7.0 without Al. As in the first experiment, tadpoles exposed to Al were smaller and were slower swimmers. Sublethal concentrations of Al at low pH may result in lowered growth rates and hence reduced body size. Swimming performance is reduced by small body size, and size-adjusted performance is further reduced by Al and low pH, which might lead to higher predation on Al-stressed tadpoles.
Article
Structure was assessed in uneven-aged stands of loblolly (Pinus taeda) and shortleaf pine (P. echinata) that were subjected to prescribed winter burns on cycles of 0, 3, 6, and 9 years. Vegetation assessments were made in late summer of 1990, 10 years after a single hardwood control treatment (basal injection of nonpine woody plants >2.5 cm in ground- line diameter with TordorP 101 R); 1 year after the fourth 3-year burn cycle; 4 years after the second 6-year burn cycle; and 1 year after the second g-year burn cycle. Compared to unburned controls, prescribed burning tended to increase (P < 0.008) percent ground cover from graminoids and composites. For understory woody plants that were >l m tall but ~2.5 cm diameter breast height (dbh), American beautyberry (Callicarpa americana) had the greatest percent ground cover on burned and unburned plots. Horizontal cover between 0- and 3-m height tended to average less (P I 0.002) with more frequent pre- scribed burning and with shorter time since burning. There were no burn treatment dif- ferences in density (P = 0.199, p = 0.853) or basal area (P = 0.477, fi = 0.898) for sapling-size stems (2.5-8.9 cm dbh), but species diversity of saplings was lower (P = 0.002) on plots prescribe burned at 3-year intervals as compared to other treatments. burning cycle, cutting cycle, Pinus echinata, Pinus taeda, plant diversity, prescribed burn- ing, selection silviculture
Article
Using field sampling and experiments in natural and artificial ponds, I studied interactions between branchiate adult mole salamanders (Ambystoma talpoideum) and lesser sirens (Siren intermedia), two top predators in temporary ponds of the southeastern United States. The abundance and distribution of these two salamanders were independent among ponds, with A. talpoideum more numerous and widespread than S. intermedia. Both species were more likely to be found in ponds near other intermittent wetlands. Within a pond, captures of these two species were negatively correlated, and a field experiment showed that paedomorphic A. talpoideum avoided traps containing S. intermedia. An experiment in artificial ponds confirmed that interactions between these two species were highly asymmetrical; S. intermedia reduced the growth and recruitment of A. talpoideum without experiencing reciprocal. positive or negative effects. These results suggest that S. intermedia competes with and is an intraguild predator of A. talpoideum, limiting its growth and controlling its recruitment.