Jerrold L. Belant

Mississippi State University, استارکویل، میسیسیپی, Mississippi, United States

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Publications (185)261.98 Total impact

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    ABSTRACT: Understanding relative hazards of wildlife to aircraft is important for developing effective management programs that can minimize hazards from wildlife strikes. Although interspecific differences in hazard level of birds and mammals on airport properties are described, no studies have quantified hazard level of bird species or identified factors that influence hazard level when birds are struck beyond airport boundaries (e.g., during aircraft climb or approach). We used Federal Aviation Administration National Wildlife Strike Database records from 1990 through 31 May 2014 to identify bird species involved most often in collisions with aircraft beyond airport boundaries in the United States and to quantify the interspecific hazard level of those birds. We also investigated whether body mass, group size (single or multiple birds), region (Flyway), and season influenced the likelihood of aircraft damage and substantial damage when strikes occurred using binary logistic regression analysis. Canada geese (Branta canadensis; n = 327), turkey vultures (Cathartes aura; 217), American robins (Turdus migratorius; 119), and mallards (Anas platyrhynchos; 107) were struck most often by aircraft beyond airport boundaries. Waterbirds (cormorants, ducks, geese, and to a lesser extent, gulls) and raptors (including vultures) were most likely to cause damage or substantial damage to aircraft when strikes occurred. Body mass was an important predictor of hazard level; group size, region, and season had lesser effects on hazard level. Management strategies to reduce bird strikes with aircraft beyond airport properties should be active throughout the year and prioritize waterbirds and raptors. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.
    No preview · Article · Feb 2016 · Journal of Wildlife Management
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    Tim L. Hiller · Jerrold L. Belant · Jeff Beringer · Andrew J. Tyre
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    ABSTRACT: Following functional extirpation in Missouri, American black bear (Ursus americanus) populations in this state have been increasing in recent years through recolonization from reestablished populations in northern Arkansas. To increase our understanding of resource selection by recolonizing black bears in the Ozark Highlands of the United States, we attached Global Positioning System (GPS) transmitters to 54 black bears during May–August 2010–2013, and used location data based on biological seasons. We constructed models with anthropogenic (distance to nearest development, distance to nearest road), biological (sex, age class, season), and environmental (distance to nearest water, land cover) categories. We used infinitely weighted logistic regression to approximate the inhomogeneous Poisson point process model for presence-only (i.e., GPS locations) data to fit models. We used Bayesian Information. Criterion and found that the best-performing model in the set of 81 models included all independent variables except sex and all combinations of 2-way interactions except those between biological covariates. Forested areas generally were more strongly selected than nonforested areas and bears generally selected areas distant from roads and other human development. However, selection for areas proximate to roads in the composite cover type (e.g., shrub–scrub, woody wetlands) occurred, where roads may have been used as travel corridors in unsuitable cover during the breeding season (ad) or dispersal (subad), or alternatively as a potential barrier, depending on road type and traffic volume. Use of apparent lower quality non-forested areas by bears suggests that the current level of human development in southern Missouri is unlikely to halt their recolonization.
    Full-text · Article · Dec 2015 · Ursus
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    ABSTRACT: Factors relevant to resource selection in carnivores may vary across spatial and temporal scales, both in magnitude and rank. Understanding relationships among carnivore occupancy, prey presence, and habitat characteristics, as well as their interactions across multiple scales, is necessary to improve our understanding of resource selection and predict population changes. We used a multi-scale dynamic hierarchical co-occurrence model with camera data to study bobcat and snowshoe hare occupancy in the Upper Peninsula of Michigan during winter 2012-2013. Bobcat presence was influenced at the local scale by snowshoe hare presence, and by road density at the local and larger scale when hare were absent. Hare distribution was related primarily to vegetation cover types, and detectability varied in space and time. Bobcat occupancy dynamics were influenced by different factors depending on the spatial scale considered and the resource availability context. Moreover, considering observed co-occurrence, we suggest that bobcat presence had a greater effect on hare occupancy than hare presence on bobcat occupancy. Our results highlight the importance of studying carnivore distributions in the context of predator-prey relationships and its interactions with environmental covariates at multiple spatial scales. Our approach can be applied to other carnivore species to provide insights beneficial for management and conservation.
    Preview · Article · Nov 2015 · PLoS ONE

  • No preview · Article · Nov 2015 · Journal of Mammalogy
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    ABSTRACT: In many temperate ecosystems animal carcasses resultant from wildlife harvest can provide a high-quality food source for myriad facultative scavengers. We investigated scavenger use of human-provisioned ungulate carrion from a fall moose (Alces alces) hunt during 2010 and 2011 on the Gustavus Forelands, Alaska, USA. Using data from remote cameras, we (1) identified the scavenger species that used these resources and (2) evaluated their spatial and temporal responses to this seasonal resource event by indexing their activity patterns and relative order of arrival at carrion sites. We also quantified the length of time carrion persisted and estimated the amount of moose biomass provisioned to vertebrate scavengers by human hunters. Our results indicated that 11 vertebrate species (five birds and six mammals) scavenged moose carrion. We found that the common raven was the only species documented at all carrion sites and the most abundant species at moose carrion sites. As a species group, corvids [black-billed magpie (Pica hudsonia), common raven (Corvus corax); 0.1 ± 2.3 days] were the first to arrive at human-provisioned moose carrion sites, whereas ursids [brown bear (Ursus arctos), black bear (U. americanus); 1.3 ± 1.0 days] arrived after corvids but sooner than expected and canids [gray wolf (Canis lupus), coyote (C. latrans); 3.9 ± 3.0] arrived later than expected compared to our null model. On average, carrion persisted >20 days and hunters provided scavengers with a minimum of 2720 kg (82.7 kg/km2) and 1815 kg (64.8 kg/km2) of moose carrion during 2010 and 2011, respectively. Understanding how scavengers, particularly large carnivores, interact with human-provisioned moose carrion at the rural–wildland interface is essential for mitigating potential human–wildlife conflicts associated with humans subsidizing predators with a high-quality food resource.
    Full-text · Article · Nov 2015 · Polar Biology
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    ABSTRACT: Increasingly, measures of glucocorticoid levels (e.g., cortisol), key components of the neuroendocrine stress axis, are being used to measure past hypothalamic-pituitary-adrenal (HPA) activity to index psychological and physiological stress exhibited by wildlife for assessing individual and population-level well-being. However, many intrinsic and extrinsic factors affect HPA activity in animals. Using American black bears (Ursus americanus; n = 116) as an ecological model and hair cortisol concentration (HCC) as an integrative measure of past HPA activity, we evaluated the influence of diet, sex and the social environment on black bear HCC in a free-ranging population that spanned adjoining ecoregions with differing densities of potential conspecific and heterospecific competitors. HCC varied by sex, with female HCC ranging from 0.6 to 10.7 pg/mg (median = 4.5 ± 1.2 mean absolute deviation [MAD]) and male HCC ranging from 0.5 to 35.1 pg/mg (median = 6.2 ± 2.6 MAD). We also observed a three-way interaction among sex, δ14C and ecoregion, which may indicate that some differences in HCC between female and male black bears results from variability in the nutritional needs of larger-bodied males relative to smaller-bodied females, slight differences in food resources use between ecoregions as well as sex-based differences regarding the social environment. Once we understand what drives sex-specific differences in HCC, HCC may aid our understanding of the physiological responses by bears and other wildlife to diverse environmental challenges.
    Preview · Article · Nov 2015 · PLoS ONE
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    ABSTRACT: Female ungulate reproductive success is dependent on the survival of their young, and affected by maternal resource selection, predator avoidance, and nutritional condition. However, potential hierarchical effects of these factors on reproductive success are largely unknown, especially in multi-predator landscapes. We expanded on previous research of neonatal white-tailed deer (Odocoileus virginianus) daily survival within home ranges to assess if resource use, integrated risk of 4 mammalian predators, maternal nutrition, winter severity, hiding cover, or interactions among these variables best explained landscape scale variation in daily or seasonal survival during the post-partum period. We hypothesized that reproductive success would be limited greater by predation risk at coarser spatiotemporal scales, but habitat use at finer scales. An additive model of daily non-ideal resource use and maternal nutrition explained the most (69%) variation in survival; though 65% of this variation was related to maternal nutrition. Strong support of maternal nutrition across spatiotemporal scales did not fully support our hypothesis, but suggested reproductive success was related to dam behaviors directed at increasing nutritional condition. These behaviors were especially important following severe winters, when dams produced smaller fawns with less probability of survival. To increase nutritional condition and decrease wolf (Canis lupus) predation risk, dams appeared to place fawns in isolated deciduous forest patches near roads. However, this resource selection represented non-ideal resources for fawns, which had greater predation risk that led to additive mortalities beyond those related to resources alone. Although the reproductive strategy of dams resulted in greater predation of fawns from alternative predators, it likely improved the life-long reproductive success of dams, as many were late-aged (>10 years old) and could have produced multiple litters of fawns. Our study emphasizes understanding the scale-dependent hierarchy of factors limiting reproductive success is essential to providing reliable knowledge for ungulate management.
    Full-text · Article · Oct 2015 · PLoS ONE
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    ABSTRACT: Dominance is a behavioural mechanism that allows individuals to access and monopolize resources which should ultimately improve their fitness. Hierarchy strength should be strongest when resources are limited; however, this relationship is not consistent. We provided abundant food to assess whether hierarchy strength was consistent with resource abundance using 9 groups of captive female white-tailed deer (Odocoileus virginianus). We further assessed how body mass, age and testosterone levels were associated with rank position. Deer displayed a weak hierarchy with a mean linearity (h) of 0.39 (SD = 0.09) and a mean directional consistency index of 0.83 (SD = 0.06). Rank was related to body mass (p = 0.004, slope = 0.011), but not age or testosterone levels (p 0.163). We demonstrate that hierarchy strength was weak in the presence of abundant food resources and suggest the possibility that dominance is a plastic behaviour that may vary with resource abundance.
    Full-text · Article · Oct 2015 · Behaviour
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    ABSTRACT: AimFunctional diversity is a relatively recent approach to quantify species diversity and may provide a better understanding of the linkages between biological diversity and ecosystem functioning. Understanding the relationships between mammal species richness and functional diversity, the factors that influence these relationships, and the spatial scale at which they operate, can improve our knowledge of ecosystem functioning and may benefit conservation planning.LocationCosta Rica (8°0′–11°14′N and 82°32′–85°56′W).Methods We evaluated spatial patterns of species richness and functional diversity for terrestrial mammal species in Costa Rica using regression techniques and assessed the influence of environmental, biological and anthropogenic factors on those patterns.ResultsEnvironmental and anthropogenic factors influenced species richness and functional diversity, while a biological factor (i.e. species' geographic origin) only influenced functional diversity. Observed patterns of species richness and functional diversity resulted in identification of three regions which could be differentiated by ecosystem type and the occurrence of bats and rodents. The spatial scale at which variation in these diversity measures also differed, with species richness most affected at fine spatial scales (local) and functional diversity best explained at the meso-scale (regional level).Main conclusionsBoth diversity measures varied spatially in relationship of examined factors, and the extent at which influencing factors affect both measures also varied across the country and scales. Our results highlight that investigating the interaction of scales is necessary for also further understanding macroecological patterns. Considering multiple measures of biological diversity and the spatial scales at which they operate may improve our understanding of biodiversity and the efficacy of species and community conservation planning.
    Full-text · Article · Oct 2015 · Diversity and Distributions
  • M. G. Gantchoff · J. L. Belant
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    ABSTRACT: We analysed coexistence patterns between two mesocarnivores, Geoffroy's cat (Leopardus geoffroyi: Felidae) and culpeo fox (Pseudalopex culpaeus: Canidae), in northern Patagonia, Argentina. We examined spatial distribution influenced by land cover, anthropogenic disturbance and invasive hare presence, and analysed temporal activity patterns and dietary composition. If competitive exclusion accounts for carnivore coexistence in this system, we predicted segregation would occur in one or more of these aspects as a mechanism for coexistence. We performed camera trapping in Nahuel Huapi National Park, from February to May 2012 and January to April 2013. Using camera detections, we analysed spatial patterns with co-occupancy modelling and temporal patterns by fitting kernel density estimates and measuring overlap. We performed a dietary meta-analysis using available literature and performed a discriminant function analysis of diet categories between species. We observed high spatial and temporal overlap between Geoffroy's cats and culpeo foxes. We found no evidence of segregation in relation to land cover occupancy, anthropogenic disturbance, invasive hare occurrence or activity patterns. Though both species consumed predominantly small and medium mammals, Geoffroy's cats consumed more birds, reptiles and amphibians, and culpeo foxes consumed more large mammals, carrion and plant material; coexistence between these two carnivores in this Patagonian protected area appears to be facilitated by diet segregation.
    No preview · Article · Sep 2015 · Austral Ecology
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    ABSTRACT: Maternal care influences offspring quality and can improve a mother's inclusive fitness. However, improved fitness may only occur when offspring quality (i.e., offspring birth mass) persists throughout life and enhances survival and/or reproductive success. Although maternal body mass, age, and social rank have been shown to influence offspring birth mass, the interdependence among these variables makes identifying causation problematic. We established that fawn birth mass was related to adult body mass for captive male and female white-tailed deer (Odocoileus virginianus), thus maternal care should improve offspring fitness. We then used path analysis to identify which maternal characteristic(s) most influenced fawn birth mass of captive female white-tailed deer. Maternal age, body mass and social rank had varying effects on fawn birth mass. Maternal body mass displayed the strongest direct effect on fawn birth mass, followed by maternal age and social rank. Maternal body mass had a greater effect on social rank than age. The direct path between social rank and fawn birth mass may indicate dominance as an underlying mechanism. Our results suggest that heavier mothers could use dominance to improve access to resources, resulting in increased fitness through production of heavier offspring.
    Full-text · Article · Aug 2015 · PLoS ONE
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    ABSTRACT: The trade-off between predator avoidance and foraging is a key decision making factor that shapes an organism's adaptive behaviour and movement patterns. Human hunters act as top predators to influence the behaviour of free-ranging mammals, including large carnivorous species such as black bears (Ursus americanus). Analysing the effects of hunting on animal behavioural patterns is essential for understanding the extent to which animals detect and respond to human-induced disturbances. To this end, we assessed whether black bear movement behaviour changed with varying risk from spatially and temporally heterogeneous human predation. Levels of risk were categorized as either low (disturbance from dog training; n=19 bears) or high (disturbance from hunting activities; n=11 bears). Road types were either paved (risk due to vehicles) or non-paved (risk due to hunters) and were used as proxies for hunting effort and amount of disturbance. We began by testing the null hypothesis that bears' distribution before the onset of human disturbance is spatially random. Next, to test temporal movement adjustment between the low and high risk levels, we measured the distance to the nearest road and the road crossing frequency using mixed effects models with risk level, time of day and sex as predictor variables. As disturbance near non-paved roads increased due to the start of the hunting activity, the mean distances of bears to non-paved roads increased while the mean distances of bears to paved roads decreased, despite the continual risk of vehicle collision. These behavioural responses were observed during day and night, with the frequency of crossing paved roads at night five times greater than in daytime during the hunting season. Our findings demonstrate that black bears are able to detect risky places and adjust their spatial movements accordingly. More specifically, bears can perceive changes in the level of risk from human hunting activities on a fine temporal scale.
    Full-text · Article · Aug 2015 · Behavioural processes
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    ABSTRACT: Ocelots Leopardus pardalis (Linnaeus, 1758) are one of the most common fe-lids in the Neotropics and in the absence of large carnivores, can function as apex predators. Despite occupying numerous habitats across its range, including human-dominated landscapes, there is limited information on how ocelots use fragmented landscapes. We radio-tracked a female ocelot in a fragmented landscape of the Caribbean region of Colombia from November 2010 to January 2011 to estimate home range and habitat use. We obtained 100 locations overall; home range size was 9.64 km 2 using the 95% fixed kernel density estimate. Rivers and roads were the main variables related with the locations and the ocelot selected for natural forests but also used disturbed habitats. Home range size and habitat use was similar to previous studies, but we observed greater use of disturbed habitats. As ocelots become the top predators in many fragmented landscapes of the Neotropics, it is important to understand how they use landscapes and could serve as surrogates for conservation.
    Full-text · Article · Aug 2015
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    ABSTRACT: Balancing the ecological importance of large carnivores with human tolerances across multiple‐use landscapes presents a complex and often controversial management scenario. Increasing cougar (Puma concolor) populations in the western United States, coupled with an increasing human population and distribution, may contribute to increased numbers of interactions and conflicts (e.g., livestock depredation) with cougars. We assessed county‐level factors associated with mortalities of cougars of different sexes and ages resulting from livestock conflicts in Oregon during 1990–2009. Factors included cougar population density, human population density, proportion of the cougar population that were juvenile males, cougar harvest, prey availability, habitat conditions, and climate measured at the county level. We used generalized linear mixed models and quasi‐likelihood Akaike's Information Criterion (QAIC) to rank models. Two of 26 models were competitive (ΔQAIC ∑w = 0.72) and both contained cougar population density and cougar harvest density; the second‐best model also included proportion of juvenile males in the population. From model‐averaging, we determined cougar mortalities associated with livestock conflicts increased with increasing cougar population density (95% CL = 0.48–1.37) and decreased with increasing cougar harvest density (95% CL = −0.58 to −0.02). An exploratory model including cougar population density, cougar harvest density, proportion of juvenile male cougars, beef cattle density, relative deer density, and all pairwise interactions was equal to the QAIC‐top model from the previous set of 26 models. Under a scenario of a high proportion (0.40) of juvenile males, number of cougar mortalities related to livestock conflicts increased 219% when cougar population density increased from 300/10,000 km2 to 400/10,000 km2. In contrast, the number of cougar mortalities decreased with increasing harvest when cougar population densities were high (500/10,000 km2), but we found no relationship at lower cougar population densities. As beef cattle densities increased, the number of cougar mortalities increased substantially (low deer populations), remained relatively low and constant (average deer population), and decreased (high deer populations). Where landowner tolerance to cougar‐livestock conflicts is an issue, wildlife managers may provide expertise to reduce conflicts by increasing density of wild ungulate prey, increasing hunter‐harvest, and reducing vulnerability of livestock, depending on factors that may be contributing to conflicts. © 2015 The Wildlife Society.
    Full-text · Article · Aug 2015 · Journal of Wildlife Management
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    ABSTRACT: Understanding species distributions and population responses to environmental parameters is important for addressing landscape-level species conservation. We assessed American black bear (Ursus americanus) resource selection based on spatial distribution of a recolonizing population in Mississippi, USA. Given the philopatric behavior of female bears and the risk-disturbance hypothesis, we predicted that bears recolonizing Mississippi would occupy areas close to their source population but avoid areas near roads and with greater human population density. Using location data from radio-collared black bears, landscape metrics, and spatial autoregressive modeling, we estimated annual population-level space use. Our results confirm that black bears recolonizing Mississippi occupy habitats proximate to source populations and avoid areas near roads as probability of bear use was greater in areas closer to source breeding populations and areas farther from roads. Land cover type, elevation, and human density did not influence black bear occurrence at the spatial resolution examined. The lack of avoidance to areas inhabited by humans was likely a consequence of overall low human density, legal protection afforded this species, and that proximity to source population likely has a greater effect on recolonization than avoidance of humans.
    No preview · Article · Jun 2015 · European Journal of Wildlife Research
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    Alexander R. Crain · Jerrold L. Belant · Travis L. DeVault
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    ABSTRACT: Wildlife incidents with aircraft are of concern in the United States as they pose a risk to human safety and economic losses for the aviation industry. Most previous research on wildlife-aircraft incidents has emphasized birds, bats, and ungulates. We queried the Federal Aviation Administration’s National Wildlife Strike Database from 1990 to 2012 to characterize carnivore incidents with U.S. civil aircraft. We found 1016 carnivore incidents with aircraft representing at least 16 species, with coyotes (n = 404) being the species most frequently struck. California and Texas had the most reported incidents and incidents were most likely to occur at night from August to November. Overall estimated damage to aircraft was US$ 7 million. Coinciding with the increase in air traffic, the rate of carnivore-aircraft incidents increased 13.1% annually from 1990 to 2012 whereas the rate of damaging incidents remained fairly constant. Due to the increase in carnivore-aircraft incidents from 1990 to 2012, we recommend further research on techniques to increase detection of carnivores and implementation and scheduled maintenance of perimeter high fences for exclusion. Additionally, we recommend increasing patrol of runways, especially during peak incident periods (July–November) and at night (2000–0600 h).
    Full-text · Article · May 2015 · Transportation Research Part D Transport and Environment
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    ABSTRACT: Costa Rica has one of the greatest percentages (26%) of protected land in the world. The National Protected Areas System (NPAS) of Costa Rica was established in 1976 and currently includes >190 protected areas within seven different protection categories. The effectiveness of the NPAS to represent species, populations, and areas with high species richness has not been properly evaluated. Such evaluations are fundamental to understand what is necessary to strengthen the NPAS and better protect biodiversity. We present a novel assessment of NPAS effectiveness in protecting mammal species. We compiled the geographical ranges of all terrestrial Costa Rican mammals then determined species lists for all protected areas and the estimated proportion of each species’ geographic range protected. We also classified mammal species according to their conservation status using the IUCN Red List of Threatened Species. We found almost complete representation of mammal species (98.5%) in protected areas, but low relative coverage (28.3% on average) of their geographic ranges in Costa Rica and 25% of the species were classified as underprotected according to a priori representation targets. Interestingly, many species-rich areas are not protected, and at least 43% of cells covering the entire country are not included in protected areas. Though protected areas in Costa Rica represent species richness well, strategic planning for future protected areas to improve species complementarity and range protection is necessary. Our results can help to define sites where new protected areas can have a greater impact on mammal conservation, both in terms of species richness and range protection.
    Full-text · Article · May 2015 · PLoS ONE
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    ABSTRACT: A primary concern for human-wildlife interactions is the potential impacts resulting from wildlife (primarily birds) collisions with aircraft. The identification of species responsible for collisions with aircraft is necessary so that airport management can develop effective strategies to reduce strikes with those species. Of particular importance in developing such strategies is the identification of regional, seasonal, and temporal patterns in collisions with unidentified bird species that may limit the effectiveness of regional habitat management to reduce bird strikes. The authors analyzed 105,529 U.S. civil aviation strike records from 1990 to 2012 in the FAA's National Wildlife Strike Database to examine patterns of collisions involving unidentified birds. Factors that affected identification were airport certification class, FAA region, mass of struck species, state species richness (if damage was reported), and interactive effects between the last four factors. Identification varied by region and declined with increasing species richness; this identification was greater for general aviation (GA) airports and the mass of struck species, especially when damage was reported. Species identification might be improved by increasing reporting efforts relative to species richness, especially by GA airport managers and operations staff, who may have a higher propensity of reporting bird strikes, and by collecting more field-based data on avian populations. The results can provide guidance for the development of airport management and personnel training.
    No preview · Article · May 2015 · Transportation Research Record Journal of the Transportation Research Board
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    ABSTRACT: American black bears (Ursus americanus) occur on numerous islands within the Apostle Islands National Lakeshore in Lake Superior, Wisconsin, USA, and provide an opportunity to better understand patterns in abundance and genetic structure among island populations. In 2002 and 2010, we derived genotypes from DNA obtained from hair samples collected at hair traps to estimate population abundance on Stockton (40.7 km2), Sand (11.9 km2), and Oak (20.6 km2; 2010 only) islands. We used Huggins closed-population mark–recapture models to estimate island-specific abundance and density. We used Program STRUCTURE and parentage analysis to examine inter-island population structure, migration patterns, and relatedness. In 2010, we estimated abundance on Stockton, Sand, and Oak islands to be 13.1 (95% CI = 12.4–13.8), 10.1 (95% CI = 9.3–11.0), and 18.1 (95% CI = 17.3–19.0) bears, with a density of 0.32, 0.85, and 0.88 bears/km2, respectively. Whereas abundance on Sand Island increased 60% since 2002 (N = 6.3, 95% CI = 4.0–8.6), abundance on Stockton declined 50% (N = 26.3, 95% CI = 24.7–27.9), including an 83% decline in detected females. Density on Oak Island was the highest reported in Wisconsin, although we identified 13 individuals as likely mates or offspring of a single male. We identified 4 genetic groups, corresponding to Stockton, Sand, Oak, and Mainland ancestry. No individuals on Stockton or Sand islands were assigned ancestry from another island, whereas one male on Oak Island was assigned Stockton ancestry. We detected individuals of predominately Mainland ancestry on all but Hermit Island, suggesting a high rate of immigration from the mainland. We suggest these islands can support high bear densities, but may undergo rapid shifts in sex-specific abundance. Genetic connectivity appears maintained by male-mediated gene flow, but a small number of wide-ranging females may sustain inter-island population viability.
    No preview · Article · May 2015 · Ursus
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    ABSTRACT: To access a free e-print version of this article, please visit this link: http://www.tandfonline.com/eprint/k2BdQiXfwuYs886GBSeE/full ------------------------------------ Capsule-- Interpretation of nest survival estimates may be improved by incorporating the search method used to locate nests as a covariate. Aims-- To compare annual survival estimates for Dickcissel Spiza americana nests and determine if incorporating search method (structured, opportunistic, or behavioural searches) improved model fit. Methods-- Dickcissel nests were located using structured, opportunistic, or behavioural searches over three years (2011–2013) in Mississippi, USA. Models were used to estimate daily survival rates (DSRs) and to analyse factors influencing nest survival. Results-- DSRs for Dickcissels were best explained by quadratic date, nest age, age found, and year, but incorporating search method improved model fit. Daily survival was 1.51 times greater for nests located using opportunistic search methods relative to structured searches, but was not significantly different between structured and behavioural searches. Conclusions-- Survival estimates varied by search method, specifically between structured searches and opportunistically located nests. This might have arisen because heterogeneity in nest placement or parental behaviour may influence the sample of nests located with a given search method. Researchers may be able to account for this potential source of bias by including search method as a model covariate when using standard survey designs or modelling approaches.
    Full-text · Article · Apr 2015 · Bird Study

Publication Stats

1k Citations
261.98 Total Impact Points

Institutions

  • 2008-2015
    • Mississippi State University
      • • Forest & Wildlife Research Center
      • • Department of Wildlife, Fisheries and Aquaculture
      استارکویل، میسیسیپی, Mississippi, United States
  • 2013
    • University of Maryland, Baltimore
      Baltimore, Maryland, United States
  • 2007
    • Michigan Technological University
      Хаутон, Michigan, United States
  • 2002-2007
    • University of Alaska Fairbanks
      • Institute of Arctic Biology
      Fairbanks, Alaska, United States