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Partial redundancy analysis (pRDA) ordination for observation frequencies of 52 camera-trapped bird and mammal taxa across 33 vernal pools in Maine during 2014–2016. Sites are black crosses, red dots are observed taxa, and vectors represent site characteristics. Labeled taxa are: MALL = mallard (Anas platyrhynchos), WODU = wood duck (Aix sponsa), AMCR = American crow (Corvus brachyrhynchos), WHDE = white-tailed deer (Odocoileus virginianus), RACC = raccoon (Procyon lotor), EAGR = eastern gray squirrel (Sciurus carolinensis), RESQ = red squirrel (Sciurus vulgaris), and EACH = eastern chipmunk (Tamias striatus). Vector labels are: Canopy.su = mean density of summer tree canopy across years, Shrub.su = mean summer shrub cover, Submerg.sp. = mean spring submerged vegetation cover; Al, Am, and Ls = mean egg mass counts for A. laterale, A. maculatum, and L. sylvaticus, respectively; and Imp100, Imp1000, and Water1000 are the percent impervious or open water cover within 100 or 1000 m of pools. Variance explained: RDA1 = 56.6%; RDA2 = 22.6%. Contours (gray) represent change in impervious cover within 100 m across ordination space
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Vernal pools in the northeastern US are of conservation concern primarily because of their role as habitat for specialized pool-breeding amphibians, but their use by birds and mammals may also be of interest, especially from the perspective of the impact of urbanization. We describe camera-trapped wildlife (CTW) at 38 vernal pools along an urban de...
Citations
... Although our study primarily focused on the type of water source as the main explanatory variable, it is important to acknowledge that several other factors can influence the selection and utilization of water sources by birds and mammals. Some potential variables, which were not included in our study but are known to impact the use of water bodies, encompass the characteristics of the vegetation growing within water bodies and their surrounding areas (Eakin et al., 2018;Votto et al., 2022), water body and landscape features such as water depth, terrain slope, distance to roads, and proximity to other water sources (Najafi et al., 2019;Pin et al., 2018), and food availability within and around the water bodies (Chaves et al., 2021;Eakin et al., 2018). Furthermore, in the case of tree holes, variations in height and connectivity of tree holes (e.g., through lianas and neighboring trees) may influence the utilization of these water sources (Cudney-Valenzuela et al., 2021). ...
... Although our study primarily focused on the type of water source as the main explanatory variable, it is important to acknowledge that several other factors can influence the selection and utilization of water sources by birds and mammals. Some potential variables, which were not included in our study but are known to impact the use of water bodies, encompass the characteristics of the vegetation growing within water bodies and their surrounding areas (Eakin et al., 2018;Votto et al., 2022), water body and landscape features such as water depth, terrain slope, distance to roads, and proximity to other water sources (Najafi et al., 2019;Pin et al., 2018), and food availability within and around the water bodies (Chaves et al., 2021;Eakin et al., 2018). Furthermore, in the case of tree holes, variations in height and connectivity of tree holes (e.g., through lianas and neighboring trees) may influence the utilization of these water sources (Cudney-Valenzuela et al., 2021). ...
Water availability significantly influences bird and mammal ecology in terrestrial ecosystems. However, our understanding of the role of water as a limiting resource for birds and mammals remains partial because most of the studies have focused on surface water bodies in desert and semi-desert ecosystems. This study assessed the use of two types of surface water bodies (waterholes and epikarst rock pools) and one arboreal (water-filled tree holes) by birds and mammals in the seasonally dry tropical forests of the Calakmul Biosphere Reserve in southern Mexico. We deployed camera traps in 23 waterholes, 22 rock pools, and 19 water-filled tree holes in this karstic region to record visits by small, medium, and large-bodied birds and mammals during the dry and rainy seasons. These cameras were set up for recording videos documenting when animals were making use of water for drinking, bathing, or both. We compared the species diversity and composition of bird and mammal assemblages using the different types of water bodies by calculating Hill numbers and conducting nonmetric multidimensional scaling (NMDS), indicator species, and contingency table analyses. There was a greater species richness of birds and mammals using surface water bodies than tree holes during both seasons. There were significant differences in species composition among bird assemblages using the different water bodies, but dominant species and diversity remained the same. Terrestrial and larger mammalian species preferentially used surface water bodies, whereas arboreal and scansorial small and medium mammals were more common in arboreal water bodies. These findings suggest that differences in water body characteristics might favor segregation in mammal activity. The different water bodies may act as alternative water sources for birds and complementary sources for mammals, potentially favoring species coexistence and increasing community resilience to environmental variation (e.g., fluctuations in water availability). Understanding how differences in water bodies favor species coexistence and community resilience is of great relevance from a basic ecological perspective but is also crucial for anticipating the effects that the increased demand for water by humans and climate change can have on wildlife viability.
... 1.6 kg P annually from vernal pools into the surrounding forests (Capps et al. 2015). While non-obligate wildlife such as turtles, snakes, birds, and mammals also use vernal pools as a source of water, refuge, or food, their presence is more difficult to document and measure (Silveira 1998;Mitchell et al. 2008;Eakin et al. 2018). Vernal pools also facilitate water storage, as the pooling of surface water allows the water to move more slowly through the system and seep into the surrounding soil. ...
... It also means including this information is low cost in terms of funds and labor. The higher likelihood of indicator species (Leibowitz 2003;Eakin et al. 2018;Hofmeister 2022). Indicator species are most heavily reliant on vernal pools, but many other species also benefit from their presence and are simply more difficult to document and measure, including birds and mammals. ...
Vernal pools are small, ephemeral wetlands that become inundated each spring and provide many ecosystem services, including providing critical habitat to amphibians and invertebrates as their temporary nature keeps them free of fish. We collected data on vernal pool characteristics throughout five Great Lakes National Parks: Pictured Rocks National Lakeshore, Sleeping Bear Dunes National Lakeshore, Apostle Islands National Lakeshore, Isle Royale National Park, and Voyagers National Parks. Our goals were to characterize and assess how vernal pools vary within and across the five national parks, and determine which characteristics are most correlated with the presence of vernal pool indicator species. We sampled 139 pools during spring of 2021 and 2022 where we collected data on pool characteristics related to hydrology, soils, vegetation, geomorphology, and indicator species. We found that vernal pool substrate and forest type does vary between the different parks. Many vernal pool qualities are driven by the type of substrate they occur on and overstory canopy species and amount of tree cover. We also created a classification system that most highly correlated to indicator species presence and can be used in remote sensing products, resulting in a three-class system based on overstory species composition: Deciduous, Coniferous, and Open. Indicator species were more likely to occur in pools with either a deciduous or open canopy than pools with a coniferous canopy. This information can be used to inform land managers within the Great Lakes of vernal pool characteristics they can expect, and which pools are hotspots for indicator species.
... Wildlife can also be sources of conflict with humans, for example when they damage vegetation, collide with motor vehicles, or transmit pathogens. As humans continue to encroach on wildlife habitat worldwide (Venter et al. 2016;Williams et al. 2020), understanding the diversity and species composition of wildlife communities, particularly in residential exclusively within non-protected areas (Cove et al. 2012;Eakin et al. 2018;Hansen et al. 2020;Kays and Parsons 2014), or deployed camera traps directly on residential properties (Hansen et al. 2020;Kays and Parsons 2014;Linske et al. 2018;Parsons et al. 2018b). To address this data gap, specifically in the US Northeast, we collected camera trap data from 22 locations (each with 3 camera traps) over three seasons in residential neighborhoods within Dutchess County, NY and applied Bayesian site-occupancy models to these data to estimate species occupancy, distribution and richness. ...
Despite the widespread adoption of motion-triggered camera traps, studies using camera traps to characterize wildlife communities in residential areas in North America are limited. To fill this data gap, we placed camera traps over three seasons in 22 residential neighborhoods within Dutchess County, NY. To account for imperfect detection, we applied individual-level and community-level Bayesian site-occupancy models to these data. Overall, we captured 64,639 independent detections over 17,820 camera trap days. We detected between 17 and 22 mammal and non-passerine bird species in each of the seasons of data collection, while our community models estimated between 24 and 33 mammal and non-passerine bird species in each season. Small, cryptic species were not reliably captured by camera traps, limiting our ability to model their occupancy. We identified five species: raccoons (Procyon lotor), eastern gray squirrels (Sciurus carolinensis), red foxes (Vulpes vulpes), Virginia opossums (Didelphis virginiana), and white-tailed deer (Odocoileus virginianus) found in all neighborhoods. The most common covariate included in our final occupancy models was the percent of area within each neighborhood that was an impervious surface, which positively affected occupancy for some species, and negatively affected occupancy for others. Forest cover, the second most common variable in our final models, negatively affected occupancy for all species. Our estimates characterize a baseline for quantifying species richness and composition in residential areas of Dutchess County, NY and surrounding regions, and offer a comparison to similar studies in natural areas. Overall, the results improve understanding of how residential landscapes affect individual species and communities.
... A Digital Elevation Model was used to calculate the TRI index through Q-GIS (source Google Satellite: Imagery © 2018 CNES/Airbug, DigitalGlobe, Landsat/Copernicus). The selected buffer size is suitable to provide information on the general environmental conditions influencing the waterbody use by terrestrial wildlife (Eakin et al., 2018). Distance to the nearest waterbody was calculated as a proxy of the waterbody isolation degree (Boix et al., 2016;Cerini et al., 2020), by measuring the minimum distance from each study SWB to the nearest known waterbody with available surface water (watercourse, wetland or pond). ...
... In the UK, 66 bird species were observed during the breeding season at 16 farmland ponds (Lewis-Phillips et al., 2019a), and slightly lower values were recorded for 25 ephemeral pools in forested landscapes from the USA (Scheffers et al., 2006;Silveira, 1998). In northeastern USA, 33 terrestrial bird species were recorded making use of 38 vernal pools (Eakin et al., 2018). Our study expands on previous research suggesting a great and overlooked importance of SWB to support farmland bird communities (Davies et al., 2016), particularly in Mediterranean agroecosystems (Armenteros et al., 2021;Zamora-Marín et al., 2021b). ...
... Interestingly, some bird species were exclusively detected at SWB sites and not in their corresponding adjacent sites (Fig. 3). This result may be explained by the fact that SWB deploy a pull effect on terrestrial wildlife, thus improving the detection probability of bird species through an increased waterbody use rate (Eakin et al., 2018;Zamora-Marín et al., 2021a). SWB may provide important ecological services for farmland bird communities at landscape scale and even driving the structure of bird communities at small spatial scales. ...
Farmland bird populations are declining worldwide as a consequence of agricultural intensifi-cation, and the loss of singular landscape elements has been suggested as one of the main drivers. This scenario of agroecosystem simplification is even more exacerbated in arid and semiarid regions, where traditional small waterbodies (SWB) are rapidly vanishing due to groundwater overexploitation and the declining extensive pastoralism. Here, we used data from breeding bird surveys at SWB and adjacent control sites to assess for the first time the landscape-scale contribution of three types of traditional SWB for supporting farmland bird communities in the most arid region of continental Europe. Four community metrics were calculated for each SWB: species richness, abundance, diversity and proportion of conservation-concern species. In general, a high proportion (71% on average) of the local breeding bird communities used SWB, irrespective of the SWB type. Cattle ponds supported a greater abundance and proportion of threatened species, whereas drinking troughs were used by more diversified bird communities. Traditional artificial pools showed intermediate values for all community metrics. Our results support that in semiarid regions any type of traditional man-made SWB, if properly designed and managed, can play a pivotal role in supporting farmland bird communities at landscape scale. Despite their ecological importance, traditional SWB are often overlooked from agri-environment schemes, and their role for supporting farmland biodiversity is rarely considered. Therefore, effective SWB management and conservation measures should be implemented in the framework of the new reform of the European Common Agricultural Policy and other similar eco-schemes in order to halt the decline of farmland biodiversity.
... Invertebrates represent the bulk of the species present in seasonal ponds and their food webs, and thus play a critical role in the trophic dynamics of seasonal ponds (Colburn et al. 2008). Beyond invertebrates, seasonal ponds provide foraging habitat for other organisms, including birds (McKinney and Paton 2009;Eakin et al. 2018), mammals (e.g., bats, shrews, foxes, hare; Brooks and Doyle 2001;Brooks and Ford 2005;Francl 2008;Eakin et al. 2018), reptiles (Refsnider and Linck 2012) and amphibians (Palik et al. 2001;Gahl et al. 2009;Schrank et al. 2015). ...
... Invertebrates represent the bulk of the species present in seasonal ponds and their food webs, and thus play a critical role in the trophic dynamics of seasonal ponds (Colburn et al. 2008). Beyond invertebrates, seasonal ponds provide foraging habitat for other organisms, including birds (McKinney and Paton 2009;Eakin et al. 2018), mammals (e.g., bats, shrews, foxes, hare; Brooks and Doyle 2001;Brooks and Ford 2005;Francl 2008;Eakin et al. 2018), reptiles (Refsnider and Linck 2012) and amphibians (Palik et al. 2001;Gahl et al. 2009;Schrank et al. 2015). ...
Seasonal ponds are small, isolated wetlands with variable hydrology, often occurring embedded in upland forests, which provide habitat for amphibians and invertebrates uniquely adapted to fishless waters. Seasonal ponds are challenging to identify due to their small size, ephemeral hydrology, diverse vegetation, and occurrence across a range of settings, yet in order to inform their conservation and management, it is essential to understand their distribution and how management impacts them. We conducted a systematic review to define and quantify attributes of seasonal ponds, summarize mapping and inventory methods, and synthesize forest harvesting impacts on ponds in the western Great Lakes and northeastern United States. Definitions of seasonal ponds differ regionally and for scientific vs. regulatory purposes; the necessity of documenting pond-dependent indicator species (e.g., fairy shrimp) is one of the most vexing inconsistencies. Seasonal ponds are most effectively mapped in the spring, using a combination of aerial photographs or radar imagery and topographic information, especially in settings with small ponds or heavy canopies. Combining these mapping efforts with carefully stratified field validation is essential for developing a regional inventory of seasonal ponds. Most guidelines intended to reduce impacts of forest harvesting on pond ecosystems rely on buffers, which most effectively minimize physical or biological impacts when most lightly treated, although some impacts (particularly water levels) appear unavoidable when any harvesting occurs adjacent to seasonal ponds. Overall, distinct physical and biological impacts of harvesting differ in magnitude and direction, though most appear to subside over multi-decadal timescales.
... If the differences between these two sites are meaningful for wildlife, we expected to nd greater presence and diversity of native mammal species in SESP. As some species are less tolerant of the impacts of urbanization than others (McKinney 2002; Eakin et al. 2018;Rodriguez et al. 2021), we also expected greater presence of less tolerant species ("urban avoiders," sensu Blair 1996) at SESP, while more tolerant species, "urban adapters," may not differ between the two green spaces, and species dependent on urbanized conditions, "urban exploiters," and non-native invasive species may be more common at JWP. This variation in tolerance of urbanization may produce differences in the species composition of the wildlife communities of the two parks, including differences in the mammalian predator guilds (Bateman and By comparing the mammalian fauna of these two parks we hoped to shed light on the scale and nature of differences in habitat value of green spaces as they exist in an urban area. ...
Urban green spaces (UGS) have the potential to play an increasingly important role in biodiversity conservation. To realize this potential, fine-scale, site-specific, and easily accessible understanding of UGS habitat value is needed, as planning and management of UGS occur primarily at local levels. This camera-trap case study compared mammalian wildlife in two large, Seattle-area UGS, St. Edward State Park (SESP) and Juanita Woodlands Park (JWP). The parks are ecologically similar, but differ in the principal dimensions of urbanization-related habitat impacts: habitat size, fragmentation, and matrix quality, with JWP more heavily urbanized than SESP. Equal sampling effort in two habitat types (riparian forest, 1157 camera-days; upland forest, 1094 camera days) documented greater native mammalian species richness and diversity in SESP in both habitats. Two species, flying squirrel and Townsend’s chipmunk, were detected only at SESP. Species occupancy patterns indicated that bobcat, Douglas squirrel and mountain beaver were more likely to be present in SESP, while raccoon, coyote, and black-tailed deer, as well as six non-native species, did not show consistent differences between parks. The predator community of SESP showed a higher overall level of activity, and differed from JWP in species’ relative prominence. These results show in a straightforward and accessible manner the critical importance of urbanization impacts in determining the capacity of UGS to support wildlife—particularly small species and “urban avoiders”—and the range of habitat value across large UGS as they exist in a metropolitan area. Species we found to be largely restricted to SESP may be tractable indicators of UGS habitat quality in the urbanized Pacific Northwest region, and SESP provides a possible example of a regional reference site for forested UGS habitat quality. Similar studies can produce analogous applied outcomes in urban settings elsewhere.
... In recent years occupancy modeling has established itself as an important tool to estimate site occupancy values in a robust manner and establish habitat relationships (Ametller et al. 2017;De Wan et al. 2009;Gibbs et al. 2017;Webb et al. 2017). Several recent studies have tended to highlight its utility in studies of urban biodiversity such as utilization of urban parks and forest by bird communities (Canedoli et al. 2018;Chibesa and Downs 2017), by taxa as diverse as mammals and salamanders (Weaver and Barrett 2018;Eakin et al. 2018) and, most recently, domestic cats (Vanek et al. 2021). ...
Given that ecological knowledge of large urban river systems is extremely sparse due to logistics and accessibility an occupancy modeling study was conducted on the resident birds of Delhi. River Yamuna passing through Delhi is a refuge for several resident and migratory species of birds but its water quality has been deteriorating due to ever growing population, contributing most of its pollution load in the urban center. The objectives of this study were 1) to determine whether the occupancy of common waterbirds varied between differential polluted sections of the river, 2) to better understand the associations between habitat variables and use of the river habitat by common waterbirds and 3) to identify whether any species or groups of species could be useful as indicators for habitat quality. The occupancy parameter Ψ was estimated for 17 common resident species among 68 species, recorded from 176 sampling locations during 2018, on the banks of river. Species occupancy was estimated as a function of habitat variables such as physico-chemical characteristic of water, solid waste, percent area of surface and emergent vegetation and human disturbance at each sampling site. The results suggest that Little Grebe (Tachybaptus ruficollis), Grey Heron (Ardea cinerea), Grey-headed Swamphen (Porphyrio poliocephalus), Eurasian Coot (Fulica atra), Common Moorhen (Gallinuala chloropus), Purple Heron (Ardea purpurea) and Little Cormorant (Microcarbo niger) are negatively associated with the Total Dissolved Solute (TDS). Interestingly, occupancy of Black-winged Stilt (Himantopus himantopus) is negatively associated with pH but positively with solid waste strongly suggesting its preference for the polluted sections of the river, possibly due to the increased availability of food. For river Yamuna, estimates of Ψ for various birds forms a baseline to study future trends. This study also indicates that species like Black-winged Stilt, can serve as an indicator of contaminated water bodies. The challenges posed by increasing urbanization and pollution to riparian bird habitats in urban areas can be effectively dealt with by incorporating such ecological knowledge with habitat restoration and conservation efforts.
... Most importantly, vernal pools are devoid of large predators such as fish, which are common predators in permanent wetlands (Zedler, 2003). Although the use of vernal pools by mammals and birds is examined less than amphibians and invertebrates, the unique nature of vernal pools is likely affecting them favorably by providing them with food resources such as amphibians (Eakin et al., 2018). ...
... A link can be made with Nummi et al. (2019) study, where they noticed that the moose prefers beaver-flooded areas with shallow waters and rich emergent vegetation (Vehkaoja and Nummi, 2015) over the non-beaver ponds. Thus, this suggests that moose may generally favor shallow water habitats, such as vernal pools, as foraging areas, which was also observed in Eakin et al. (2018) study. We observed higher amounts of Carex sp. and Salix sp. in vernal pools compared to permanent wetlands. ...
... Finally, like for the roe deer, hare activity may also be affected by human disturbance. According to Eakin et al. (2018), the snowshoe hare, Lepus americanus, prefers vernal pools with less urban development, which is supporting our result that hares may favor habitats less disturbed by humans. The feces tracking result supports the result of camera traps: hares being more common by vernal pools than permanent wetlands, even though the difference was only suggestive not reaching statistical significance. ...
Biodiversity and habitats are under threat from many factors such as human population increase, habitat loss, fragmentation, and climate change. In freshwater habitats, including wetlands, biodiversity is expected to decline on a greater scale than in terrestrial ecosystems. Ephemeral wetlands are little studied habitats compared to other wetlands, such as permanent lakes and rivers. The purpose of this study was to investigate the vertebrate fauna present by ephemeral vernal pools and to see whether vernal pools increase the activity and diversity of vertebrates in a boreal forest ecosystem in northern Europe. We studied the activity and species richness of birds and mammals with direct observations, camera traps, faeces tracking, and snap-trapping by ten vernal pools and ten permanent wetlands. Bird activity was higher in the spring period in vernal pools than in permanent wetlands. For large mammals, both activity and species richness were greater around vernal pools than by permanent wetlands. Of individuals species, the moose (Alces alces), roe deer (Capreolus capreolus), and hares (Lepus europaeus and Lepus timidus) used vernal pools significantly more between seasons compared to permanent wetlands. Small mammal activity was higher by vernal pools in April, while in May and June the pattern reversed. In the light of these results, vernal pools seem to have different importance and use depending on the vertebrate group, e.g., for sheltering, foraging, resting, nesting, or thermoregulation.
... In the UK, 66 bird species were observed during breeding season at farmland ponds (Lewis-Phillips et al. 2019a), whereas 58 species were recorded at seasonal pools in predominantly urbanized areas from USA(Mckinney and Paton 2009), and slightly lower values were recorded for ephemeral pools in forested landscapes from the last country(Silveira 1998;Scheffers et al. 2006). In northeastern USA, 33 terrestrial bird species were recorded making use of vernal pools(Eakin et al. 2018). Overall, different types of SWB seem to make a nonnegligible contribution to local bird communities across different landscapes around the world. ...
... In this sense, our study strengthens previous evidence on the importance of SWB to support terrestrial bird communities(Hanowski et al. 2006;Davies et al. 2016;Lewis-Phillips et al. 2019b;Zamora-Marín et al. 2021c).Interestingly, some bird species were exclusively detected at SWB sites and not in their adjacent control sites(Figure 3). This result may be explained by the fact that SWB deploy a pull effect on terrestrial wildlife, thus improving the detection probability of bird species through an increased waterbody use rate(Mckinney and Paton 2009;Eakin et al. 2018;Zamora-Marín et al. 2021b). SWB provide important ecological services for terrestrial bird communities at landscape scale having an effect even in the structure of terrestrial bird communities at small spatial scales. ...
In the last decades, the biodiversity associated to freshwater ecosystems has experienced a more marked decline than the biota inhabiting terrestrial or marine environments. Among the different types of freshwater ecosystems, small waterbodies are of particular interest due to their great contribution to the total water surface on the earth. However, the potential of small waterbodies for supporting biodiversity has not been recognized until some years ago. Today, there is a broad scientific consensus on the important role of small waterbodies to maintain freshwater biodiversity at local and regional scale. Nevertheless, several aspects related to their importance for terrestrial wildlife remain unexplored, as well as their potential for replacing natural ponds in our future human-dominated landscapes. The main objective of this PhD thesis is to assess the potential of small waterbodies to be used by animal communities (especially terrestrial birds) in semiarid regions. For that purpose, 39 small waterbodies distributed along the Province of Murcia (SE Spain) were surveyed, belonging to three traditional typologies: drinking troughs, cattle ponds and traditional artificial pools. Bird surveys were conducted through direct observation within a portable hide and encompassing three visits within the same breeding period (April-July). Surveys began at sunrise, lasted three hours and all birds observed within a 10-m buffer around each waterbody were recorded. Mist-netting and conventional video cameras were also used as alternative survey methods to direct observation, in order to compare the effectiveness of different techniques to detect bird species at small waterbodies. Moreover, traditional lineal transects (1 km) were conducted around each waterbody in order to get a representative picture of the terrestrial breeding bird community inhabiting the surrounding landscape. Additionally, breeding amphibians and freshwater macroinvertebrates were also inventoried for each waterbody through dip netting. As a complement to these data on aquatic communities, similar information already available for small waterbodies from France and Switzerland was also used. Direct observation and the combined method of direct observation plus video cameras yielded greater estimates than mist-netting for detecting bird species associated to small waterbodies. Thus, both observational methods provided more representative data than mist netting on the bird use of small waterbodies. A total of 80 bird species were recorded making use of the studied small waterbodies. Drinking troughs supported the higher estimated terrestrial bird richness, followed by cattle ponds and traditional artificial pools. A positive relation was observed between bird richness and environmental heterogeneity. Cattle ponds were particularly important for threatened and conservation concern species. The three types of traditional small waterbodies were used, on average, by the 71% of the terrestrial bird species inhabiting the surrounding landscape, thus highlighting the great importance of these small habitats for terrestrial wildlife at local scale. In relation to aquatic communities, different types of artificial waterbodies made a complementary contribution to the regional richness of amphibians, water beetles and aquatic snails. On average, artificial waterbodies supported the 50% of the regional richness of the three animal groups, thus highlighting artificial waterbodies make a moderate contribution to the freshwater biodiversity at regional scale. However, a greater richness of aquatic taxa was found for natural ponds located in the same region than the studied artificial waterbodies. Therefore, artificial waterbodies could not compensate the loss of natural ponds in future human-dominated landscapes.
... The greater Bangor, Maine, area is located in the glaciated northeastern United States, a region historically dominated by mixed coniferoushardwood forest (Eakin et al. 2018). Bangor encompasses 90 km 2 with a population of 33,000 (U.S. Census Bureau 2011). ...
Wood frogs (Lithobates sylvaticus) are threatened by habitat degradation associated with suburbanization. Suburban development near pools may affect larvae with ramifications for population persistence and vitality. We studied larval development and documented key vernal pool and terrestrial characteristics within 1000 m of 43 pools across the suburban development gradient near Bangor, Maine, USA. Specifically, we examined how survival and morphological characteristics (e.g., developmental phenology, condition, body length, and tail length and shape) varied with characteristics at pool and landscape scales. Secondarily, we explored associations between morphology and survival. Differences in tadpole morphology were associated with suburban land development, hydrology, within‐pool vegetation indicative of light availability at the water's surface, and density of pool‐breeding amphibian egg masses. Across all pools, tadpoles had delayed development and were larger in pools with longer hydroperiods, while tadpoles in suburban pools developed earlier and were larger than those in rural pools with comparable hydroperiods. Tadpoles developed later and had longer tails in pools with greater canopy cover. Morphology profiles also differed between rural and suburban sites and among years. Survival in suburban pools was predicted to be 15 times greater than in rural pools, but across all pools (including those at intermediate intensities of suburbanization), survival was not predicted to vary with either morphology or site characteristics. No strong relationship existed between developmental phenology and any condition or size metric. Because rural and suburban tadpoles responded similarly to within‐pool conditions, our results support the need to maintain natural hydrology and vegetation conditions in pools even in developing areas. Although we detected benefits to tadpoles with increasing suburbanization, suburbanization is well known to extirpate breeding populations; thus, it is likely that wood frog population declines associated with suburbanization are responding to stressors beyond the pool at terrestrial life stages.
