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The widespread eradication of large carnivores and subsequent expansion of top mesopredators has the potential to impact species and community interactions with ecosystem‐wide implications. An example of these trophic dynamics is the widespread establishment of coyotes following extirpation of wolves and mountain lions in eastern North America. Here, we examined occupancy of three carnivores in northern New York considering both environmental/habitat factors and interspecific interactions. We estimated the co‐occurrence of coyotes, fishers, and martens from a landscape‐scale winter camera trap survey repeated annually for three years. Martens occurred independently of both coyotes and fishers, while fishers and coyotes displayed positive intraguild interactions that were constant across the landscape. Both marten and fisher first‐order occupancy were driven by a combination of biotic and abiotic factors, with both species displaying positive associations with forest cover but antithetical responses to average snow depth. The integral and antithetical role of snow depth in driving the occurrence of martens (positive) and fishers (negative) in the landscape indicates that future climatic warming could reduce the availability of current spatial refuges for martens created by severe winter conditions. Climate‐driven alterations to established competitive interactions and co‐existence patterns between marten and fisher have critical implications for the species survival and conservation. We provide correlational evidence consistent with the potential for positive top–down effects of dominant mesocarnivores on subordinate species, with fisher occupancy increasing conditional on the presence of coyotes across the landscape. These findings align with the hypothesis that under certain conditions, coyotes may facilitate certain subordinate carnivores. The evidence produced here is consistent with hypotheses on the dynamic nature of trophic niches. We demonstrate the need to consider the interplay between climate, habitat, and interspecific interactions to understand wildlife occupancy patterns and inform wildlife management in a rapidly changing world. [ABSTRACT FROM AUTHOR]

Effective population size estimates are critical information needed for evolutionary predictions and conservation decisions. This is particularly true for species with social factors that restrict access to breeding or experience repeated fluctuations in population size across generations. We investigated the genomic estimates of effective population size along with diversity, subdivision, and inbreeding from 162,109 minimally filtered and 81,595 statistically neutral and unlinked SNPs genotyped in 437 grey wolf samples from North America collected between 1986 and 2021. We found genetic structure across North America, represented by three distinct demographic histories of western, central, and eastern regions of the continent. Further, grey wolves in the northern Rocky Mountains have lower genomic diversity than wolves of the western Great Lakes and have declined over time. Effective population size estimates revealed the historical signatures of continental efforts of predator extermination, despite a quarter century of recovery efforts. We are the first to provide molecular estimates of effective population size across distinct grey wolf populations in North America, which ranged between Ne ~ 275 and 3050 since early 1980s. We provide data that inform managers regarding the status and importance of effective population size estimates for grey wolf conservation, which are on average 5.2–9.3% of census estimates for this species. We show that while grey wolves fall above minimum effective population sizes needed to avoid extinction due to inbreeding depression in the short term, they are below sizes predicted to be necessary to avoid long‐term risk of extinction. [ABSTRACT FROM AUTHOR]

Mapped representations of species−habitat relationships often underlie approaches to prioritize area‐based conservation strategies to meet conservation goals for biodiversity. Generally a single surrogate species is used to inform conservation design, with the assumption that conservation actions for an appropriately selected species will confer benefits to a broader community of organisms. Emerging conservation frameworks across western North America are now relying on derived measures of intactness from remotely sensed vegetation data, wholly independent from species data. Understanding the efficacy of species‐agnostic planning approaches is a critical step to ensuring the robustness of emerging conservation designs. We developed an approach to quantify 'strength of surrogacy', by applying prioritization algorithms to previously developed species models, and measuring their coverage provided to a broader wildlife community. We used this inference to test the relative surrogacy among a suite of species models used for conservation targeting in the endangered grasslands of the Northern Sagebrush Steppe, where careful planning can help stem the loss of private grazing lands to cultivation. In this test, we also derived a simpler surrogate of intact rangelands without species data for conservation targeting, along with a measure of combined migration representative of key areas for connectivity. Our measure of intactness vastly outperformed any species model as a surrogate for conservation, followed by that of combined migration, highlighting the efficacy of strategies that target large and intact rangeland cores for wildlife conservation and restoration efforts. [ABSTRACT FROM AUTHOR]

Based on what we learned, we devised a methodology (Figure 4) for conservation organizations to evaluate evidence use internally through document analysis of conservation plans, interviews, and surveys of conservation planners. Survey of NCC conservation planners To complement the document analysis, we designed and distributed a questionnaire survey (Appendix S5) to NCC conservation planners ( I n i = 35). Keywords: document analysis; ecosystem management; evidence-based conservation; knowledge synthesis; monitoring and evaluation; North America; science-practice divide; traditional ecological knowledge; América del Norte; análisis de documentos; conocimiento ecológico tradicional; conservación basada en evidencias; división ciencia-práctica; gestión ambiental; monitoreo y evaluación; síntesis del conocimiento; ; ; ; ; ; ; ; EN document analysis ecosystem management evidence-based conservation knowledge synthesis monitoring and evaluation North America science-practice divide traditional ecological knowledge América del Norte análisis de documentos conocimiento ecológico tradicional conservación basada en evidencias división ciencia-práctica gestión ambiental monitoreo y evaluación síntesis del conocimiento 1 15 15 08/01/22 20220801 NES 220801 INTRODUCTION With biodiversity loss accelerating globally, the need to act quickly, efficiently, and effectively has prompted calls to critically examine and improve the information guiding conservation decisions. [Extracted from the article]

For capital‐breeding insects, all resources available for adult metabolic needs are accumulated during larval feeding. Therefore, body size at adult eclosion represents the total energetic capacity of the individual. For female capital breeders, body size is strongly correlated with lifetime fecundity, while in males, body size, which correlates with fitness, is less understood. In capital‐breeding species with wingless, flightless, or dispersal‐limited females, flight potential for male Lepidoptera has important implications for mate‐finding and may be correlated with body size. At low population densities, failure to mate has been identified as an important Allee effect and can drive the success or failure of invasive species at range edges and in species of conservation concern. Th capital‐breeding European subspecies of Lymantria dispar (L.), was introduced to North America in 1869 and now ranges across much of eastern North America. In L. dispar, females are flightless and mate‐finding is entirely performed by males. We quantified male L. dispar flight capacity and propensity relative to morphological and physiological characteristics using fixed‐arm flight mills. A range of male body sizes was produced by varying the protein content of standard artificial diets while holding other dietary components constant. Wing length, a proxy for body size, relative thorax mass, and forewing aspect were all important predictors of total flight distance and maximum speed. These results have important implications for mate‐finding and invasion dynamics in L. dispar and may apply broadly to other capital‐breeding insects. [ABSTRACT FROM AUTHOR]

Green ash (Fraxinus pennsylvanica) is the most widely distributed ash tree in North America. Once common, it has experienced high mortality from the non‐native invasive emerald ash borer (EAB; Agrilus planipennis). A small percentage of native green ash trees that remain healthy in long‐infested areas, termed "lingering ash," display partial resistance to the insect, indicating that breeding and propagating populations with higher resistance to EAB may be possible. To assist in ash breeding, ecology and evolution studies, we report the first chromosome‐level assembly from the genus Fraxinus for F. pennsylvanica with over 99% of bases anchored to 23 haploid chromosomes, spanning 757 Mb in total, composed of 49.43% repetitive DNA, and containing 35,470 high‐confidence gene models assigned to 22,976 Asterid orthogroups. We also present results of range‐wide genetic variation studies, the identification of candidate genes for important traits including potential EAB‐resistance genes, and an investigation of comparative genome organization among Asterids based on this reference genome platform. Residual duplicated regions within the genome probably resulting from a recent whole genome duplication event in Oleaceae were visualized in relation to wild olive (Olea europaea var. sylvestris). We used our F. pennsylvanica chromosome assembly to construct reference‐guided assemblies of 27 previously sequenced Fraxinus taxa, including F. excelsior. Thus, we present a significant step forward in genomic resources for research and protection of Fraxinus species. [ABSTRACT FROM AUTHOR]

Calls for organizational change have pervaded wildlife conservation in recent decades, driven by a shift in values that is reshaping the social landscape of wildlife management. As this process unfolds, wildlife agencies in North America seek new ways to remain relevant, focusing primarily on how they might expand support for their ongoing work. Less attention, however, has been given to expanding opportunities for a value‐diverse public to directly shape what that work might entail. As citizen ballot initiatives, lawsuits, and other forms of political intervention continue to complicate wildlife management, we ask whether agencies—who have historically shied away from value‐based conflict in pursuit of apolitical scientific management—can remain relevant without fundamental changes to their governance structures. Using data from a 2018 survey of wildlife values among the American public (n = 24,393) and state wildlife agency employees (n = 10,191), we explore the extent to which public values are mirrored within wildlife agencies and examine the implications of a "values gap" on the long‐term sustainability of technocratic wildlife management. Findings suggest that as the public's perspectives on wildlife conservation change, governance reform may become a growing area of focus in the years ahead. [ABSTRACT FROM AUTHOR]

Domestic cats Felis catus have a complex and contentious history. They fill multiple societal roles (e.g. as pest controllers and companion animals), which has led to a variety of animal welfare, conservation, and human health concerns. Popular press articles play an important role in how people learn about key issues surrounding cats, but they may present some issues more frequently than other issues.We conducted a global media content analysis of 796 articles in the English‐language media from 1990 to 2018 on issues related to free‐roaming cats, such as their environmental impacts, the threats and welfare issues cats face, and how they are managed. We aimed to determine whether non‐experts learning about the issues around free‐roaming cats exclusively from the popular press would be exposed to multiple stakeholder views or opinions.Over 95% of articles analysed were from North America. Most of the people interviewed in the popular press were from non‐governmental organizations, mainly from cat welfare or cat rights groups (which are often focused on only one side of the issue). Researchers, shelter organizations, veterinarians, and groups that have different opinions than cat rights or welfare organizations on how to resolve issues surrounding free‐roaming cats were rarely interviewed by the popular press. Most articles focused on cat welfare issues and the management strategies of euthanasia or trap–neuter–release (TNR), whereas less than one‐third of the articles acknowledged that cats have any impact on wildlife or the broader environment.We found that the popular press often presented an oversimplified picture of issues related to free‐roaming cats and provided unbalanced coverage. We also show evidence of framing by the popular press, including mainly presenting the viewpoints and perspectives from animal welfare and rights groups, focusing on TNR or euthanasia as the only viable cat management strategies when many alternatives exist and often have greater support from experts, and discussing the impacts of cats on birds and small mammals but not reptiles or amphibians. A free Plain Language Summary can be found within the Supporting Information of this article. A free Plain Language Summary can be found within the Supporting Information of this article. [ABSTRACT FROM AUTHOR]

Conservation of threatened and endangered species often involves large‐scale collaboration across jurisdictional boundaries, but such efforts are typically hampered by a lack of consistent monitoring data at local, regional, and species‐distributional scales. Contemporary methods of genetic monitoring that are grounded in sequencing‐based approaches offer a powerful means to achieve the data consistency necessary for conservation of high‐profile species. Here, we describe the collaborative, multiagency development of a genotyping‐in‐thousands by sequencing panel for genetic monitoring of threatened Bull Trout Salvelinus confluentus across its range in North America. The resulting panel consists of 266 single nucleotide polymorphisms, a subset of which differentiate Salvelinus species (Arctic Char S. alpinus, Brook Trout S. fontinalis, Bull Trout, Dolly Varden S. malma, Lake Trout S. namaycush, and Whitespotted Char S. leucomaenis), as well as one sex ID locus. We then used case studies from the Pacific Northwest and northern Rocky Mountains to demonstrate the efficacy of the panel for addressing local conservation needs (e.g., genetic variation, genetic differentiation, genetic assignment tests, and number of effective breeders) and compatibility with legacy data sets. Future genotyping with this panel will provide opportunities for improved conservation prioritization across the species range and collaboration among the numerous agencies charged with conserving this species. This effort provides framework to develop population genetic tools that will contribute to robust and efficient monitoring of biodiversity. [ABSTRACT FROM AUTHOR]

For many ecosystems, feral horses are increasingly becoming an important if not dominant component of ungulate biomass and hence influence on community dynamics. Yet we still know little of how horses contribute to key ecological interactions including predator‐prey and indirect competitive relationships at a community level. Notably, feral species like horses can exhibit life‐history traits that differ from that of native (mainly artiodactyl) herbivore competitors. Artificial selection for traits like increased, early, or extended reproduction that have yet to be reversed by natural selection, coupled with naturally selected differences in anatomy and behavior, in addition to unique management objectives for horses compared to other species, means that the dynamics of feral horse populations are not likely to align with what might be expected of other large herbivores. Unexpected population dynamics and inherent biological asymmetries between native ungulates and feral horses may therefore influence the former via direct competition for shared resources and through enemy‐mediated interactions like apparent competition. In several localities feral horses now co‐exist with multiple native prey species, some of which are in decline or are species at risk. Compounding risks to native species from direct or indirect competitive exclusion by horses is the unique nature and socio‐political context of feral horse management, which tends towards allowing horse populations to be limited largely by natural, density‐dependent factors. We summarize the inherent asymmetries between feral horse biology and that of other ungulate prey species with consequences for conservation, focusing on predator‐prey and emerging indirect interactions in multi‐prey systems, and highlight future directions to address key knowledge gaps in our understanding of how feral horses may now be contributing to the (re)structuring of food webs. Observations of patterns of rapid growth and decline, and associated skews in sex ratios of feral horse populations, indicate a heightened potential for indirect interactions among large ungulate prey species, where there is a prevalence of feral horses as preferred prey, particularly where native prey are declining. In places like western North America, we expect predator‐prey interactions involving feral horses to become an increasingly important factor in the conservation of wildlife. This applies not only to economically or culturally important game species but also at‐risk species, both predators (e.g., wolves [Canis lupus], grizzly bears [Ursus arctos]) and prey (e.g., woodland caribou [Rangifer tarandus caribou]), necessitating an ecological understanding of the role of horses in natural environments that goes beyond that of population control. © 2021 The Wildlife Society. Feral horses now constitute a significant component of prey biomass in many ecosystems, yet little is known about predator‐prey interactions involving horses despite their potential to negatively affect native species. Understanding such interactions and in particular indirect interactions like apparent competition will be critical for managing horses and their role in contemporary food webs. [ABSTRACT FROM AUTHOR]

In order to apply, promote and consolidate the actions and strategies of conservation of a species in danger of extinction, it is desirable to have the most detailed information possible about its habitat and the variables that affect it. In this study, we examined how temperature, soil pH, precipitation and physiography affect occurrence of Taxus globosa, an endangered species in Central and North America. The medical importance (contains taxol, a substance to treat cancer) of this plant and its endemic status make it a highly priority species that requires all efforts to preserve it. Hypothesis evaluation of the abiotic variable–probability of occurrence relationships we did by using the generalized additive model with a Bayesian approach. Small climatic intervals we observed and response curves were asymmetric in most cases. Variables that showed statistical significance in the analyses were the mean temperature in the warmest month, mean annual temperature and the summer dryness index. The findings contribute to the scientific basis for the conservation and management of the species and could implement specific actions, such as the exact location of sites in the wildlife for assisted propagation trials, to establish or expand natural protected areas based on the altitudinal gradient or suitable climate ranges. [ABSTRACT FROM AUTHOR]

Anthropogenic habitat modification is a major driver of global biodiversity loss. In North America, one of the primary sources of habitat modification over the last 2 decades has been exploration for and production of oil and natural gas (hydrocarbon development), which has led to demographic and behavioral impacts to numerous wildlife species. Developing effective measures to mitigate these impacts has become a critical task for wildlife managers and conservation practitioners. However, this task has been hindered by the difficulties involved in identifying and isolating factors driving population responses. Current research on responses of wildlife to development predominantly quantifies behavior, but it is not always clear how these responses scale to demography and population dynamics. Concomitant assessments of behavior and population‐level processes are needed to gain the mechanistic understanding required to develop effective mitigation approaches. We simultaneously assessed the demographic and behavioral responses of a mule deer population to natural gas development on winter range in the Piceance Basin of Colorado, USA, from 2008 to 2015. Notably, this was the period when development declined from high levels of active drilling to only production phase activity (i.e., no drilling). We focused our data collection on 2 contiguous mule deer winter range study areas that experienced starkly different levels of hydrocarbon development within the Piceance Basin. We assessed mule deer behavioral responses to a range of development features with varying levels of associated human activity by examining habitat selection patterns of nearly 400 individual adult female mule deer. Concurrently, we assessed the demographic and physiological effects of natural gas development by comparing annual adult female and overwinter fawn (6‐month‐old animals) survival, December fawn mass, adult female late and early winter body fat, age, pregnancy rates, fetal counts, and lactation rates in December between the 2 study areas. Strong differences in habitat selection between the 2 study areas were apparent. Deer in the less‐developed study area avoided development during the day and night, and selected habitat presumed to be used for foraging. Deer in the heavily developed study area selected habitat presumed to be used for thermal and security cover to a greater degree. Deer faced with higher densities of development avoided areas with more well pads during the day and responded neutrally or selected for these areas at night. Deer in both study areas showed a strong reduction in use of areas around well pads that were being drilled, which is the phase of energy development associated with the greatest amount of human presence, vehicle traffic, noise, and artificial light. Despite divergent habitat selection patterns, we found no effects of development on individual condition or reproduction and found no differences in any of the physiological or vital rate parameters measured at the population level. However, deer density and annual increases in density were higher in the low‐development area. Thus, the recorded behavioral alterations did not appear to be associated with demographic or physiological costs measured at the individual level, possibly because populations are below winter range carrying capacity. Differences in population density between the 2 areas may be a result of a population decline prior to our study (when development was initiated) or area‐specific differences in habitat quality, juvenile dispersal, or neonatal or juvenile survival; however, we lack the required data to contrast evidence for these mechanisms. Given our results, it appears that deer can adjust to relatively high densities of well pads in the production phase (the period with markedly lower human activity on the landscape), provided there is sufficient vegetative and topographic cover afforded to them and populations are below carrying capacity. The strong reaction to wells in the drilling phase of development suggests mitigation efforts should focus on this activity and stage of development. Many of the wells in this area were directionally drilled from multiple‐well pads, leading to a reduced footprint of disturbance, but were still related to strong behavioral responses. Our results also indicate the likely value of mitigation efforts focusing on reducing human activity (i.e., vehicle traffic, light, and noise). In combination, these findings indicate that attention should be paid to the spatial configuration of the final development footprint to ensure adequate cover. In our study system, minimizing the road network through landscape‐level development planning would be valuable (i.e., exploring a maximum road density criteria). Lastly, our study highlights the importance of concomitant assessments of behavior and demography to provide a comprehensive understanding of how wildlife respond to habitat modification. © 2021 The Wildlife Society. SUMMARY OF CONCLUSIONS AND MANAGEMENT IMPLICATIONS: Adult female mule deer showed substantial behavioral plasticity in the face of natural gas development, with no apparent demographic consequences. Topographically diverse winter range with adequate vegetation providing sufficient food and cover allow deer to alter behavior in an adaptive manner, and similar features should be considered in future development planning. [ABSTRACT FROM AUTHOR]

Long‐distance migration presents complex conservation challenges, and migratory species often experience shortfalls in conservation due to the difficulty of identifying important locations and resources throughout the annual cycle. In order to prioritize habitats for conservation of migratory wildlife, it is necessary to understand how habitat needs change throughout the annual cycle, as well as to identify key habitat sites and features that concentrate large numbers of individuals and species. Among long‐distance migrants, sea ducks have particularly complex migratory patterns, which often include distinct post‐breeding molt sites as well as breeding, staging and wintering locations. Using a large set of individual tracking data (n = 476 individuals) from five species of sea ducks in eastern North America, we evaluated multi‐species habitat suitability and partitioning across the breeding, post‐breeding migration and molt, wintering and pre‐breeding migration seasons. During breeding, species generally occupied distinct habitat areas, with the highest levels of multi‐species overlap occurring in the Barrenlands west of Hudson Bay. Species generally preferred flatter areas closer to lakes with lower maximum temperatures relative to average conditions, but varied in distance to shore, elevation and precipitation. During non‐breeding, species overlapped extensively during winter but diverged during migration. All species preferred shallow‐water, nearshore habitats with high productivity, but varied in their relationships to salinity, temperature and bottom slope. Sea ducks selected most strongly for preferred habitats during post‐breeding migration, with high partitioning among species; however, both selection and partitioning were weaker during pre‐breeding migration. The addition of tidal current velocity, aquatic vegetation presence and bottom substrate improved non‐breeding habitat models where available. Our results highlight the utility of multi‐species, annual‐cycle habitat assessments in identifying key habitat features and periods of vulnerability in order to optimize conservation strategies for migratory wildlife. [ABSTRACT FROM AUTHOR]

The "green wave" hypothesis posits that during spring consumers track spatial gradients in emergent vegetation and associated foraging opportunities. This idea has largely been invoked to explain animal migration patterns, yet the general phenomenon underlies trends in vertebrate reproductive chronology as well. We evaluated the utility of this hypothesis for predicting spatial variation in nest initiation of greater sage‐grouse (Centrocerus urophasianus), a species of conservation concern in western North America. We used the Normalized Difference Vegetation Index (NDVI) to map the green wave across elevation and then compiled dates and locations of >450 sage‐grouse nests from 20 study sites (2000–2014) to model nest initiation as a function of the start of the growing season (SOS), defined here as the maximum daily rate of increase in NDVI. Individual sites were drawn from three ecoregions, distributed over 4.5° latitude, and spanning 2,300 m in elevation, which captured the climatic, edaphic, and floristic diversity of sagebrush ecosystems in the southern half of current sage‐grouse range. As predicted, SOS displayed a significant, positive relationship with elevation, occurring 1.3 days later for each 100 m increase in elevation. In turn, sage‐grouse nest initiation followed SOS by 22 ± 10 days (r2 =.57), with hatch dates falling on or just prior to the peak of the growing season. By timing nesting to the green wave, sage‐grouse chicks hatched when the abundance of protein‐rich invertebrate biomass is hypothesized to be nearing a seasonal high. This adaptation likely represents a strategy for maximizing reproductive success in the arid, variable environments that define sagebrush ecosystems. Given projected changes in climate and land use, these results can be used to predict periods of relative sensitivity to habitat disturbance for sage‐grouse. Moreover, the near real‐time availability of satellite imagery offers a heretofore underutilized means of mapping the green wave, planning habitat restoration, and monitoring range conditions. [ABSTRACT FROM AUTHOR]

North America has a diverse array of mammalian species. Model projections indicate significant variations in future climate conditions of North America, and the habitats of woodland mammals of this continent may be particularly sensitive to changes in climate.We report on the potential spatial distributions of 13 wide‐ranging, relatively common species of North American woodland mammals under future climate scenarios.We examined the potential influence of the mean and seasonal climate variables on the distribution of species. Presence‐only occurrence records of species, four predictor variables, two future climate scenarios (Representative Concentration Pathways 4.5 and 8.5), and two time steps (current and 2070) were used to build species' distribution models using a maximum entropy algorithm (MaxEnt).Our results suggested that overall, 11 of the 13 species are likely to gain climatically suitable space (regions where climate conditions will be similar to those of area currently occupied) at the continental scale, but American marten Martes americana and 'woodland' caribou Rangifer tarandus are likely to lose suitable climate range by 2070. Furthermore, climate space is likely to be expanding northwards under future climate scenarios for most of the mammals, and many jurisdictions in the border region between Canada and the USA are likely to lose iconic species, such as moose Alces alces. We identified regions as potential in situ and ex situ climate change refugia, which are increasingly considered to be important for biodiversity conservation.The model results suggest significant implications for conservation planning for the 13 mammalian species under global climate change, especially at fine spatial scales. Numerous species that are presently common at their southern range edge will be functionally or completely extirpated in 50 years. The potential in situ and ex situ climate change refugia could provide an effective support for adaptive strategies aimed at species conservation planning. [ABSTRACT FROM AUTHOR]

The effects that microorganisms (bacteria, viruses and fungi) have on their hosts remain unexplored for most vulture species. This is especially relevant for vultures, as their diet consists of carcasses in various stages of decomposition, which are breeding grounds for potentially pathogenic microorganisms. Here we review current knowledge of bacterial, viral and mycotic microorganisms present in wild vultures. We consider their potential to cause disease in vultures and whether this poses any population‐level threats. Furthermore, we address the question of whether vultures may act as disease spreaders or mitigators. We found 76 articles concerning bacterial, viral and mycotic microorganisms present in 13 vulture species, 57 evaluating bacteria, 13 evaluating viruses and six evaluating mycotic microorganisms. These studies come from all continents where vultures are present, but mainly from Europe and North America, and the most studied species was the Griffon Vulture Gyps fulvus. We found that vultures are colonized by zoonotic pathogens, and even host‐specific human pathogens. Some recorded bacteria showed multi‐antibiotic resistance, especially those that can be associated with anthropogenic food subsides such as supplementary feeding stations. We found evidence that vulture health can be affected by some microorganisms, producing a wide array of clinical alterations that have the potential to influence mortality risk and fitness. We did not find clear scientific evidence that vultures play an epidemiological role spreading microorganisms to humans and other species. However, there is evidence that vultures could prevent the spread of infectious diseases through their removal of decomposing organic material. The evaluation of vulture exposure to microorganisms is of fundamental importance to design better conservation policies for this threatened group, which may serve a key role as ecosystem cleaners. [ABSTRACT FROM AUTHOR]

The Sage Grouse Centrocercus urophasianus is a species of conservation concern throughout its range in western North America. Since the 1950s, the high count of males at leks has been used as an index for monitoring populations. However, the relationship between this lek‐count index and population size is unclear, and its reliability for assessing population trends has been questioned. We used non‐invasive genetic mark‐recapture analysis of faecal and feather samples to estimate pre‐breeding population size for the Parachute‐Piceance‐Roan, a small, geographically isolated population of Sage Grouse in western Colorado, during two consecutive winters from 2012 to 2014. We estimated total pre‐breeding population size as 335 (95% confidence interval (CI): 287–382) in the first winter and 745 (95% CI: 627–864) in the second, an approximate doubling in abundance between years. Although we also observed a large increase in the spring lek‐count index between those years, high male count data poorly represented mark‐recapture estimates of male abundance in each year. Our data suggest that lek counts are useful for detecting the direction and magnitude of large changes in Sage Grouse abundance over time but they may not reliably reflect small changes in abundance that may be relevant to small populations of conservation concern. [ABSTRACT FROM AUTHOR]

Emerging fungal diseases have become challenges for wildlife health and conservation. North American hibernating bat species are threatened by the psychrophilic fungus Pseudogymnoascus destructans (Pd) causing the disease called white‐nose syndrome (WNS) with unprecedented mortality rates. The fungus is widespread in North America and Europe, however, disease is not manifested in European bats. Differences in epidemiology and pathology indicate an evolution of resistance or tolerance mechanisms towards Pd in European bats. We compared the proteomic profile of blood plasma in healthy and Pd‐colonized European Myotis myotis and North American Myotis lucifugus in order to identify pathophysiological changes associated with Pd colonization, which might also explain the differences in bat survival. Expression analyses of plasma proteins revealed differences in healthy and Pd‐colonized M. lucifugus, but not in M. myotis. We identified differentially expressed proteins for acute phase response, constitutive and adaptive immunity, oxidative stress defence, metabolism and structural proteins of exosomes and desmosomes, suggesting a systemic response against Pd in North American M. lucifugus but not European M. myotis. The differences in plasma proteomic profiles between European and North American bat species colonized by Pd suggest European bats have evolved tolerance mechanisms towards Pd infection. [ABSTRACT FROM AUTHOR]

Declines in the spatial extent of the sagebrush ecosystem have prompted the consideration of conservation efforts that view the greater sage‐grouse (Centrocercus urophasianus; sage‐grouse) as an umbrella species at landscape scales. Conservation strategies that focus on an umbrella species, however, may have unintended negative consequences for co‐occurring species at finer scales. In North America, grassland and shrubland songbird populations are declining faster than other avian groups. Conservation of sage‐grouse habitats may protect songbird habitats where distributions overlap. To assess the umbrella species concept at fine scales, we quantified nest‐site selection for a sagebrush‐obligate songbird, the Brewer's sparrow (Spizella breweri). We then compared the fine‐scale habitat variables that influenced Brewer's sparrow nest‐site selection with fine‐scale nest‐site selection for sage‐grouse in the Powder River Basin region of northeastern Wyoming, USA. We modeled nest‐site selection using conditional logistic regression for Brewer's sparrow (2016–2017) and logistic regression for sage‐grouse (2004–2007). Both species selected nest sites with higher visual obstruction, shrub height, and branching density, although the selection for higher shrub height was stronger for sage‐grouse. Brewer's sparrows selected nest shrubs with higher percentage of living foliage (vigor), and the opposite was shown for sage‐grouse. At the nest site, based on the variables we measured, our results suggest that Brewer's sparrows and sage‐grouse select for similar habitat attributes, with the exception of shrub vigor of the nest shrub. The stronger selection for more vigorous shrubs in Brewer's sparrows may be because they nest in shrubs, rather than on the ground under shrubs (as in sage‐grouse). Most of the conservation objectives for protection of sage‐grouse habitats appear to be beneficial or inconsequential for Brewer's sparrow. Local habitat management for sage‐grouse as a proxy for conservation of other species may be justified if the microhabitat preferences of the species under the umbrella are understood to avoid unintentional negative effects. © 2019 The Wildlife Society. At the nest‐shrub and nest‐patch scale, greater sage‐grouse is an effective umbrella for Brewer's sparrow in our region. Local habitat management for greater sage‐grouse as a proxy for conservation of other species may be justified if the microhabitat preferences of the species under the umbrella are well understood to avoid unintentional negative effects. [ABSTRACT FROM AUTHOR]

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Aim: Estimating the distribution and abundance of wildlife is an essential task in species conservation, wildlife management and habitat prioritization. Although a host of methods and tools have been proposed to accomplish this undertaking, several challenges remain in accurately forecasting occurrence and abundance for highly mobile species. Exhibiting extensive geographic ranges with seasonally varying local occupancy, migratory ducks are exemplar highly mobile species and are foci for waterfowl conservation and management globally. With the goal of informing species conservation and management, our aim was to leverage citizen science data to estimate occurrence and relative abundance for ten dabbling duck species across the continental United States. Location: Conterminous United States. Methods: We applied spatially and temporally explicit Bayesian hierarchical modelling to jointly estimate season‐specific occurrence and relative abundance for ten dabbling duck species in the Genus Anas. Our conditionally dependent model design enabled relative abundance estimates to be informed by occurrence probability while accounting for cumulative spatial and temporal errors across shared model components. Results: Outcomes suggest that although dabbling duck distributions show little inter‐annual variability at the continental scale, local relative abundances may differ year to year. Commensurate with being highly mobile migratory species, estimates indicate considerable intra‐annual variation with occurrence probability, local abundance and habitat preferences differing by season and species. Main conclusions: Our approach offers a powerful and flexible framework for quantifying intra‐/inter‐annual duck occurrence and relative abundance while accounting for spatial, temporal and data collection biases. We believe that model produced maps can be applied to inform waterfowl conservation and management throughout the continental United States. [ABSTRACT FROM AUTHOR]

A global decline in large trees, largely driven by anthropogenic influences, has potentially dire consequences for cavity-dependent wildlife. For several species of conservation concern in western North America, including Pacific martens (Martes caurina), fishers (Pekania pennanti), and spotted owls (Strix occidentalis), large live and dead trees (snags) with cavities are forest structural elements that are requisite to fulfilling life history requirements. More than a century may be necessary for trees to develop cavities of a suitable size for use by martens, fishers, and owls, yet the relative amount of time that such trees persist as usable prior to senescence is largely unknown, despite the implications for how forests are managed as habitat for these wildlife species. To address this uncertainty, in 2016, we re-located 44 live trees and snags identified as marten rest structures between 2009 and 2012 in the Lassen National Forest, California. Upon re-location, we assessed structure persistence by determining whether structures had changed type (e.g., a live tree that died and transitioned to a snag) or usability (any structure that was degraded to a point where it was no longer usable by a marten). After 5–7 yr, 25% (n = 11) of marten rest structures changed type and 16% (n = 7) appeared to be unusable—a stark contrast compared to a similar study investigating persistence of fisher rest structures, which documented one-third of the change in structure type and no change in usability over roughly twice the return interval (8–12 yr). Our results emphasize the vast disparity between the lengthy period required for trees to become suitable formarten use and the potentially short period for which they may remain usable.We suggest that forest managers consider the importance of these fine-scale forest structural elements when developing broad-scale strategies to reduce fire risk and improve resilience in western North American forests. [ABSTRACT FROM AUTHOR]

The effects that fishes have on rates of one or more ecosystem processes (hereafter referred to as functional effects) are often invoked as an important reason for imperilled species conservation. However, the degree to which we understand these effects is rarely evaluated for most groups of fishes. We assessed how well the functional effects of freshwater and diadromous fishes, one of the most imperilled groups of animals, are quantified to date. We found that 88% of studies considering the functional effects of imperilled North American fishes were conducted on one family, Salmonidae. Studies of the functional effects of fishes were also concentrated in Pacific drainages of North America, with few studies in hotspots of imperilled fish diversity such as the Southeastern United States, the arid Southwest and central Mexico. Our results demonstrate the vast taxonomic and geographic gaps in our functional understanding of imperilled fishes and highlight the need to broaden this work to justify the argument that they are functionally important in the ecosystems they inhabit. [ABSTRACT FROM AUTHOR]

Accurate knowledge of geographic ranges and genetic relationships among populations is important when managing a species or population of conservation concern. Along the western coast of Canada, a subspecies of the northern goshawk (Accipiter gentilis laingi) is legally designated as Threatened. The range and distinctness of this form, in comparison with the broadly distributed North American subspecies (Accipiter gentilis atricapillus), is unclear. Given this morphological uncertainty, we analyzed genomic relationships in thousands of single nucleotide polymorphisms identified using genotyping‐by‐sequencing of high‐quality genetic samples. Results revealed a genetically distinct population of northern goshawks on the archipelago of Haida Gwaii and subtle structuring among other North American sampling regions. We then developed genotyping assays for ten loci that are highly differentiated between the two main genetic clusters, allowing inclusion of hundreds of low‐quality samples and confirming that the distinct genetic cluster is restricted to Haida Gwaii. As the laingi form was originally described as being based on Haida Gwaii (where the type specimen is from), further morphological analysis may result in this name being restricted to the Haida Gwaii genetic cluster. Regardless of taxonomic treatment, the distinct Haida Gwaii genetic cluster along with the small and declining population size of the Haida Gwaii population suggests a high risk of extinction of an ecologically and genetically distinct form of northern goshawk. Outside of Haida Gwaii, sampling regions along the coast of BC and southeast Alaska (often considered regions inhabited by laingi) show some subtle differentiation from other North American regions. These results will increase the effectiveness of conservation management of northern goshawks in northwestern North America. More broadly, other conservation‐related studies of genetic variation may benefit from the two‐step approach we employed that first surveys genomic variation using high‐quality samples and then genotypes low‐quality samples at particularly informative loci. [ABSTRACT FROM AUTHOR]

ABSTRACT: Waterfowl monitoring, research, regulation, and adaptive planning are leading the way in supporting science‐informed wildlife management. However, increasing societal demands on natural resources have created a greater need for adaptable and successful linkages between waterfowl science and management. We presented a special session at the 2016 North American Duck Symposium, Annapolis, Maryland, USA on the successes and challenges of linking research and management in waterfowl conservation, and we summarize those thoughts in this commentary. North American waterfowl management includes a diversity of actions including management of harvest and habitat. Decisions for waterfowl management are structured using decision analysis by incorporating stakeholder values into formal objectives, identifying research relevant to objectives, integrating scientific knowledge, and choosing an optimal strategy with respect to objectives. Recently, the consideration of the value of information has been proposed as a means to evaluate the utility of research designed to meet objectives. Despite these advances, the ability to conduct waterfowl research with direct management application may be increasingly difficult in research institutions for several reasons including reduced funding for applied research and the lower perceived value of applied versus theoretical research by some university academics. In addition, coordination between researchers and managers may be logistically constrained, and communication may be ineffective between the 2 groups. Strengthening these links would help develop stronger and more coordinated approaches for the conservation of waterfowl and the wetlands upon which they depend. © 2017 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Management of many North American forests is challenged by the need to balance the potentially competing objectives of reducing risks posed by high-severity wildfires and protecting threatened species. In the Sierra Nevada, California, concern about high-severity fires has increased in recent decades but uncertainty exists over the effects of fuel-reduction treatments on species associated with older forests, such as the california Spotted Owl (Strix occidentalis occidentalis). Here, we assessed the effects of forest conditions, fuel reductions, and wildfire on a declining population of Spotted owls in the central Sierra Nevada using 20 years of demographic data collected at 74 Spotted Owl territories. Adult survival and territory colonization probabilities were relatively high, while territory extinction probability was relatively low, especially in territories that had relatively large amounts of high canopy cover (≥70%) forest. Reproduction was negatively associated with the area of medium-intensity timber harvests characteristic of proposed fuel treatments. our results also suggested that the amount of edge between older forests and shrub/sapling vegetation and increased habitat heterogeneity may positively influence demographic rates of Spotted Owls. Finally, high-severity fire negatively influenced the probability of territory colonization. Despite correlations between owl demographic rates and several habitat variables, life stage simulation (sensitivity) analyses indicated that the amount of forest with high canopy cover was the primary driver of population growth and equilibrium occupancy at the scale of individual territories. Greater than 90% of medium-intensity harvests converted high-canopy-cover forests into lower-canopy-cover vegetation classes, suggesting that landscape-scale fuel treatments in such stands could have short-term negative impacts on populations of california Spotted Owls. Moreover, high-canopy-cover forests declined by an average of 7.4% across territories during our study, suggesting that habitat loss could have contributed to declines in abundance and territory occupancy. We recommend that managers consider the existing amount and spatial distribution of high-canopy forest before implementing fuel treatments within an owl territory, and that treatments be accompanied by a rigorous monitoring program. [ABSTRACT FROM AUTHOR]

The North American Breeding Bird Survey, Christmas Bird Count, and regional and national conservation assessments provide convincing evidence that the short-eared owl ( Asio flammeus) is experiencing a range-wide, long-term decline in abundance in North America. However, the species has received little conservation or research attention. The short-eared owl is vulnerable to decline because it relies heavily on large, intact grasslands and a specialized diet of unpredictable small mammal prey. The species' nomadic movements compound these vulnerabilities by making a decline difficult to detect with current monitoring programs while obfuscating stewardship responsibilities for managers. The primary threat to the species is loss, fragmentation, and degradation of large tracts of native grasslands and wetlands. We propose the following conservation priorities to better understand and begin addressing the short-eared owl's decline: 1) better define and protect important habitats; 2) improve population monitoring; 3) determine seasonal and annual movements; 4) re-evaluate NatureServe's short-eared owl national conservation classifications; 5) develop management plans and tools; and 6) classify raptors, including short-eared owls, as migratory birds in Canada. We contend that the short-eared owl's need for habitat conservation at large spatial scales, status as a predator, and high reproductive potential that affords the species capacity to recover, make it an effective and useful candidate as an umbrella species for grassland conservation. © 2014 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Aim New conservation approaches that account for broad-scale ecological processes must underpin decisions about conservation planning in the world's remaining wilderness areas. Our goal is to make the relevant tools and methods that have been developed by conservation scientists accessible to conservation practitioners working towards wilderness preservation. Location Wilderness areas, in particular the North American boreal region. Methods We describe prominent spatial tools from natural resource management, landscape ecology and conservation biology for incorporating natural disturbance dynamics into systematic conservation planning. Then, we identify emerging methods that combine and customize these types of tools to account for interacting ecological processes in wilderness conservation plans with a specific focus on conserving natural disturbances in the North American boreal region. Results Two classes of tools are well suited to the task of conservation planning in dynamic landscapes: site-selection tools (e.g. Marxan and Zonation) and process-based modelling tools (e.g. CONSERV and LANDIS- II). Four methods for explicitly including natural disturbance dynamics into conservation plans emerge from the combination of these tools: spatial catalysts combined with site-selection tools, probability theory combined with site-selection tools, spatial simulation models and spatial simulation models combined with site-selection tools. Main conclusions Globally, there are few wilderness areas remaining; therefore, there is increasing impetus to effectively protect the world's remaining intact areas. Careful combinations of probabilistic models, such as Markov chain models, or spatial simulation tools, such as CONSERV and Spatially Explicit Landscape Event Simulator, with site-selection tools, such as Benchmark Builder and Marxan, are promising approaches for accounting for natural disturbance dynamics when land use planning in wilderness areas such as the North American boreal region. The protection of natural disturbance dynamics will play an increasingly important role in the long-term persistence of biodiversity in earth's remaining wilderness areas as ongoing anthropogenic disturbances and climate change imperil broad-scale ecological processes. [ABSTRACT FROM AUTHOR]

Decisions affecting wildlife management and conservation policy of imperiled species are often aided by population models. Reliable population models require accurate estimates of vital rates and an understanding of how vital rates vary geographically. The eastern massasauga ( Sistrurus catenatus catenatus) is a rattlesnake species found in the Great Lakes region of North America. Populations of the eastern massasauga are fragmented and only a few areas harbor multiple, sizable populations. Eastern massasauga research has typically focused on single populations or local metapopulations but results suggest that demographic parameters vary geographically. We used 21 radiotelemetry datasets comprising 499 telemetered snakes from 16 distinct locations throughout the range of the eastern massasauga to characterize geographic patterns of adult survival using the known-fate model in Program MARK. Annual adult survival ranged from 0.35 to 0.95 (mean = 0.67) and increased along a southwest to northeast geographic axis. Further analysis of 6 datasets indicated no consistent difference in survival between males and females. Our results provide a better understanding of the relationship between survivorship and geography for the eastern massasauga and suggest that such variation should be incorporated into population models as well as local and regional management plans. © 2012 The Wildlife Society. [ABSTRACT FROM AUTHOR]

The North American population of king eiders ( Somateria spectabilis) has declined by more than 50% since the late 1970s for unknown reasons. King eiders spend most of their lives in remote areas, forcing managers to make regulatory and conservation decisions based on very little information. We incorporated available published estimates of vital rates with new estimates to build a female, stage-based matrix population model for king eiders and examine the processes underlying population dynamics of king eiders breeding at 2 sites, Teshekpuk and Kuparuk, on the coastal plain of northern Alaska and wintering around the Bering Sea (2001-2010). We predicted a decreasing population ( λ = 0.981, 95% CI: 0.978-0.985), and that population growth was most sensitive to changes in adult female survival (sensitivity = 0.92). Low duckling survival may be a bottleneck to productivity (variation in ducking survival accounted for 66% of retrospective variation in λ). Adult survival was high (0.94) and invariant ( ${\hat {\sigma }}^{2} $ = 0.0002, 95% CI: 0.0000-0.0007); however, catastrophic events could have a major impact and we need to consider how to mitigate and manage threats to adult survival. A hypothetical oil spill affecting breeding females in a primary spring staging area resulted in a severe population decline; although, transient population dynamics were relatively stable. However, if no catastrophic events occur, the more variable reproductive parameters (duckling and nest survival) may be more responsive to management actions. Published 2012. This article is a U.S. Government work and is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

Animal populations at northern range limits may use habitat differently from those at range cores, requiring distinct conservation plans. Snakes are ectotherms that often have very specific requirements, but few studies have focused on the effect of northern latitudes on habitat selection by grassland snakes. We studied movement and habitat selection of 2 sympatric snake species at their northern range limits on the North American Great Plains: the eastern yellow-bellied racer ( Coluber constrictor flaviventris, hereafter racer), a Threatened species in Canada, and the bullsnake ( Pituophis catenifer sayi), which is listed as Data Deficient. Both of these species are potentially vulnerable to extinction in Canada because of habitat loss. Snakes from our study populations traveled up to 10-times farther from winter dens and occupied home ranges 3-104 times larger than populations further south. Both snake species moved from winter dens in the slopes of a major river valley to habitat in adjacent lowlands, including riparian zones (racers) and hilly areas with native grass species (bullsnakes). Multivariate modeling revealed that proximity to retreat sites was a significant predictor of snake site use for both species. Considering the need for winter dens and summering areas, our data suggest that snakes in northern latitudes should ideally have much larger protected areas compared to snakes near the core of their range. An alternative strategy is to conserve corridors linking wintering dens and summer habitats. Retreat sites such as burrows and shrubs are critical components of local habitat and should be included in conservation plans. © 2011 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Wetlands in the Upper Mississippi River and Great Lakes Region (UMRGLR) must annually sustain populations of migrating waterfowl from the mid-continent of North America. We used multi-stage sampling to estimate plant and invertebrate food biomasses (kg/ha) for ducks in 3 wetland habitat types at 6 stop-over locations in the UMRGLR during 2006 and 2007. Total biomass was greatest in palustrine emergent (PEM; ${\bar {x}}$ = 208 kg/ha, SE = 23, median = 120), followed by palustrine forested (PF; ${\bar {x}}$ = 87 kg/ha, SE = 7; median = 43), and lacustrine-riverine (LR; ${\bar {x}}$ = 52 kg/ha, SE = 7; median = 27) wetlands. Ducks that foraged in forested and LR wetlands encountered the least food abundance during spring in the UMRGLR. Our estimates of food abundance were the lowest reported among other landscape scale surveys from mid-continent North America. About 1 in every 5 PEM wetlands and over half of our PF and LR wetlands that we sampled contained <50 kg/ha of food, suggesting many had little or no forage value to ducks during spring. Biomass of plant foods generally exceeded invertebrate biomass in all habitat types, although invertebrate biomass estimates exceeded plant biomass in 8 of 29 sites when considered by wetland type and year. Total food biomass estimates varied widely ( ${\bar {x}}$ = 6-425 kg/ha) between years and among habitats; thus, using global arithmetic means to estimate food abundance for conservation planning obscures fine scale temporal and spatial variation that may be necessary for management on local and sub-regional levels. Distributions of food biomass estimates were right-skewed, causing us to question whether arithmetic means realistically represent levels of food abundance that all ducks encounter during spring migration. Alternative measures of central tendency (e.g., median) may be more biologically realistic, particularly if spring-migrating ducks are not distributed in an ideal-free manner with respect to food abundance. Future research should determine how ducks distribute themselves in relation to variation in food abundance in space and time during spring migration to strengthen the biological approach to conservation planning in non-breeding Joint Venture areas of the North American Waterfowl Management Plan. © 2011 The Wildlife Society. [ABSTRACT FROM AUTHOR]

The Public Trust Doctrine (PTD) is considered the cornerstone of the North American Model of Wildlife Conservation. Effective application of the PTD requires a clear understanding of the doctrine and appropriate behavior by trustees, trust managers, and beneficiaries. Most PTD literature refers generically to the role of the government as the people's trustee, without addressing the differences between the legislative, executive, and judicial branches of government in the United States or recognizing the distinction between elected and appointed officials and career civil servants. Elected and appointed officials, especially in the legislative branch, have policy-level decision-making authority that makes them trustees of the people's wildlife under the PTD. In contrast, career professionals working for state wildlife agencies (SWA's) have ministerial duties as trust managers. The differences between the roles of trustees and trust managers are important. By focusing on their role as trust managers, while supporting and respecting the role of elected and appointed officials as trustees, SWA professionals can more effectively advance application of the PTD. [ABSTRACT FROM AUTHOR]

Geographic patterns of species distributions and the factors contributing to species endangerment are necessary for the development of integrative conservation strategies. Freshwater mussels Unionidae have among the highest levels of imperilment recorded in North America. This paper describes the biogeography and diversity of Unionidae along climate and habitat gradients in Texas, evaluates human impact, and identifies the hot spots of diversity and endemism that should be targeted for conservation. Texas, North America. Unionids were surveyed in all major Texas river basins in 2003-2009. Multivariate statistics were used to test for differences in environmental parameters and among unionid assemblages in different bioprovinces, and to determine to what extent the multivariate pattern of species distribution was affected by environmental factors. To estimate human impact, we examined the relationship between human population density and the proportion of rare species, as well with the proportion of historically present species that persist in the watershed. Correlation between biotic and environmental similarity matrices indicated concordance in the differences among unionid assemblages and environmental factors that could cause these differences. Lake surface evaporation rate and percentage of forest cover in the watershed were among the most important parameters explaining the differences in unionid assemblages. Human population density was negatively correlated with the proportion of rare species. The proportion of species found live relative to the total number of live and relic species found in our surveys and to the number of historically known species decreased with the increase in human population density. Climate, landscape, geology, and land use type were important factors influencing unionid distribution patterns among biotic provinces. Increased human population density was associated with the loss of rare species over several decades, but this loss was not recognized because of a lack of assessing the conservation status of unionids. [ABSTRACT FROM AUTHOR]

Wildlife population models are potentially valuable for conservation planning. Validation is necessary to ensure that models are sufficiently robust for predicting management outcomes consistent with conservation objectives. Sorensen et al. (2008) produced a model of woodland caribou (Rangifer tarandus) population growth rate that was recently modified and used as a predictive tool at several scales. We computed confidence intervals and evaluated the performance of this model using novel data. Confidence intervals were wide, and results suggested that the model may have a positive bias, resulting in over-estimation of population growth rates, as well as low predictive power. Wide confidence intervals mean that current understanding of factors governing woodland caribou herd dynamics is not sufficient for wildlife managers to make reliable projections of responses to management. [ABSTRACT FROM AUTHOR]

Chlorinated hydrocarbon concentrations in eggs of fish-eating birds from contaminated environments such as the Great Lakes of North America tend to be highly intercorrelated, making it difficult to elucidate mechanisms causing reproductive impairment, and to ascribe cause to specific chemicals. An information- theoretic approach was used on data from 197 salvaged bald eagle (Haliaeetus leucocephalus) eggs (159 clutches) that failed to hatch in Michigan and Ohio, USA (1986–2000). Contaminant levels declined over time while eggshell thickness increased, and by 2000 was at pre-1946 levels. The number of occupied territories and productivity increased during 1981 to 2004. For both the entire dataset and a subset of nests along the Great Lakes shoreline, polychlorinated biphenyls (ΣPCBs, fresh wet wt) were generally included in the most parsimonious models (lowest-Akaike's information criterion [AICs]) describing productivity, with significant declines in productivity observed above 26 µg/g ΣPCBs (fresh wet wt). Of 73 eggs with a visible embryo, eight (11%) were abnormal, including three with skewed bills, but they were not associated with known teratogens, including ΣPCBs. Eggs with visible embryos had greater concentrations of all measured contaminants than eggs without visible embryos; the most parsimonious models describing the presence of visible embryos incorporated dieldrin equivalents and dichlorodiphenyldichloroethylene (DDE). There were significant negative correlations between eggshell thickness and all contaminants, with ΣPCBs included in the most parsimonious models. There were, however, no relationships between productivity and eggshell thickness or Ratcliffe's index. The ΣPCBs and DDE were negatively associated with nest success of bald eagles in the Great Lakes watersheds, but the mechanism does not appear to be via shell quality effects, at least at current contaminant levels, while it is not clear what other mechanisms were involved. Environ. Toxicol. Chem. 2010;29:1581–1592. © 2010 SETAC [ABSTRACT FROM AUTHOR]

Quantifying sources of variation in demographic rates can provide insight into processes underlying population dynamics and subsequently direct wildlife conservation. In the context of avian life history, understanding patterns of variation in survival rates of breeding females is particularly relevant because this cohort often has a disproportionately large effect on population dynamics. We estimated survival probability for 144 adult female harlequin ducks (Histrionicus histrionicus) that we marked with radiotransmitters and tracked at 4 breeding areas in western North America. Model selection results indicated both regional and temporal variation in survival rates, with most mortality attributed to predation. Cumulative survival probability (6SE) during the 100-day study period was lower at 2 sites in the Rocky Mountains of Alberta, Canada (AB1 and AB2: 0.75 6 0.11) than in the Coast Mountains of British Columbia, Canada (BC: 0.88 6 0.08) or the Cascade Mountains of Oregon, USA (OR: 0.89 6 0.08). Survival also was lower during incubation than nest-initiation or brood-rearing stages at all 4 study areas. In comparison to other annual cycle stages and locations, harlequin duck mortality rates were highest on the breeding grounds, suggesting that management actions designed to reduce mortality during breeding would achieve meaningful population-level benefits. [ABSTRACT FROM AUTHOR]

Population trend data from the North American Breeding Bird Survey (BBS) have been used to identify conservation priorities and justify major conservation initiatives. Yet the BBS has been criticized for potential habitat bias and reliance on abundance indices to estimate trends. We compared 1992-2003 BBS trend estimates to trend estimates derived from bird-banding data collected as part of the Monitoring Avian Productivity and Survivorship (MAPS) program for 36 wood warbler species. Similarity in trends between the 2 monitoring programs at the survey-wide and program-wide scales suggested that each program can provide accurate trend information. The MAPS program, however, was designed primarily to complement (rather than duplicate) count-based efforts, such as the BBS, by providing estimates or indices of demographic rates. Demographic data from MAPS can be used to lend insight into proximate (demographic) causes of population trends and inform management. We illustrate this with analyses of 1992-2003 MAPS data for yellow warbler (Dendroica petechia). We used reverse-time capture-recapture models to evaluate importance of new recruits (including immigrating adults and young from the previous year) relative to surviving adults in explaining variation in trend among BBS physiographic strata. We included the number of young per adult captured (an index of productivity) as a covariate in models to assess effects of productivity on trends. Survival was the key demographic driver of recent population trends. Comparison of MAPS productivity indices and adult apparent survival rate estimates to BBS trend estimates largely confirmed this inference. We suggest that increased MAPS coverage, better coordination between MAPS and the BBS, and continued development of analytical methods that link the 2 programs will enhance the value of these monitoring efforts to land managers and conservation planners working at a variety of spatial scales. [ABSTRACT FROM AUTHOR]

Determining population size and long-term trends in population size for species of high concern is a priority of international, national, and regional conservation plans. Long-billed curlews (Numenius americanus) are a species of special concern in North America due to apparent declines in their population. Because long-billed curlews are not adequately monitored by existing programs, we undertook a 2-year study with the goals of 1) determining present long-billed curlew distribution and breeding population size in the United States and 2) providing recommendations for a long-term long-billed curlew monitoring protocol. We selected a stratified random sample of survey routes in 16 western states for sampling in 2004 and 2005, and we analyzed count data from these routes to estimate detection probabilities and abundance. In addition, we evaluated habitat along roadsides to determine how well roadsides represented habitat throughout the sampling units. We estimated there were 164,515 (SE = 42,047) breeding long-billed curlews in 2004, and 109,533 (SE = 31,060) breeding individuals in 2005. These estimates far exceed currently accepted estimates based on expert opinion. We found that habitat along roadsides was representative of long-billed curlew habitat in general. We make recommendations for improving sampling methodology, and we present power curves to provide guidance on minimum sample sizes required to detect trends in abundance. [ABSTRACT FROM AUTHOR]

Conservation of the wolverine (Gulo gulo) at the southern extent of its North American range requires reliable understandings of past and present distribution patterns and broad-scale habitat relations. We compiled 820 verifiable and documented records of wolverine occurrence (specimens, DNA detections, photos, and accounts of wolverines being killed or captured) in the contiguous United States from museums, the literature, and institutional archives. We spatially referenced 729 records with areal precision ≤1 township (93.2 km²) and temporal precision ≤10 years. Historical records (1827-1960) were located primarily in the western mountains and Great Lakes region. However, our data suggest that the historical distribution of wolverines in the Cascade Range and Sierra Nevada was disjunct, contradicting previous interpretations. Our results indicate that wolverine range in the contiguous United States had contracted substantially by the mid-1900s. Current records (1995-2005) are limited to north-central Washington, northern and central Idaho, western Montana, and northwestern Wyoming. We investigated potential relations between wolverines and alpine vegetation, cold temperatures, and spring snow cover by comparing the distribution of historical wolverine records with Kuchler's potential natural vegetation types, Holdridge's climatic life zones, and EASE snow-cover maps during the latter portion of the wolverine denning period (15 Apr-14 May). In the western mountains, historical wolverine records generally occurred in or near alpine vegetation and climatic conditions, especially at the limits of their distribution in the Cascade Range, Sierra Nevada, and southern Rocky Mountains. However, the only habitat layer that fully accounted for historical distribution patterns was spring snow cover. Causal factors for the extirpation of wolverines from the southern portions of their range in the contiguous United States are unknown, but are likely related to high levels of human-caused mortality and low to nonexistent immigration rates. [ABSTRACT FROM AUTHOR]

Although lead shot has been banned for waterfowl hunting in North America, some predators continue to exhibit elevated lead burdens, which has been attributed to ingesting metallic lead from other projectiles. Few studies have investigated residual lead fragments in hunted upland animals. Therefore, specific portals for lead entering wildlife food chains remain largely unknown. Prairie dogs (Cynomys spp.) are shot for recreation with minimal regulation in western North America. Because recreational shooters mostly use expanding bullets and rarely remove or bury carcasses, shot prairie dogs could make lead accessible to predators and scavengers. To determine whether and to what degree shot prairie dogs carry lead fragments, we analyzed carcasses shot by recreational shooters with 2 bullet types. Bullet 13T, e influenced the probability of bullet fragments being retained in carcasses; 87% of prairie dogs shot with expanding bullets contained bullet fragments, whereas 7% of carcasses shot with non expanding bullets did. The amount of bullet fragments per carcass also differed between hailer t types: carcasses shot with expanding bullets contained a mean of 228.4 mg of the lead-containing bullet core and 74.4 mg of the copper alloy jacket, whereas carcasses shot with non expanding bullets averaged only 19.g mg of the core and 23.2 mg of the jacket. Lead fragments in carcasses shot with expanding bullets were small in size; 73% of all lead mass in each carcass was from fragments that weighed <25 mg each, small enough to be easily ingested and absorbed by secondary consumers. The amount of lead in a single prairie dog carcass shot with an expanding bullet is potentially sufficient to acutely poison scavengers or predators. Therefore, shot prairie dogs may provide an important portal for lead entering wildlife food chains and may pose risks to raptors and carnivores. Managers should consider measures, such as using non expanding or lead-free ammunition, to reduce the likelihood of lead consumption and poisoning in upland wildlife. [ABSTRACT FROM AUTHOR]

Several studies have reported climate-associated changes in phenotypically plastic traits of amphibians, yet it remains unknown whether amphibians can manifest an evolutionary response to global climate change at the rate and magnitude that it is occurring. To assess this issue, we examined temporal change in the morphology of the red-backed salamander (Plethodon cinereus ), a small, abundant woodland salamander distributed widely in eastern North America with two distinct morphotypes: striped individuals associated with cooler microclimates and unstriped individuals associated with warmer microclimates. We compiled morph frequencies for 50,960 individual salamanders from 558 sites as recorded in the published literature and in unpublished field notes of herpetologists between 1908 and 2004. We observed that striping probability increased with increasing latitude, longitude, and elevation and decreased (from 80% to 74% range wide) with time. The combined forces of regional climate warming and, particularly, forest disturbance have evidently been sufficient to cause morphological evolution in this amphibian over the last century. [ABSTRACT FROM AUTHOR]

In the last decade, there has been increasing interest—particularly among international nongovernmental and multilateral development organizations—in evaluating the effectiveness of conservation and development projects. To evaluate success, we need more comprehensive and case-specific information on how conservation decisions are made. I report on a database that synthesizes information on 27 marine conservation planning cases from around the world. I collected data on each case's geographic scale, primary planning objective and outcome, legal and institutional context, degree of stakeholder involvement, and the ecological criteria and tools used to facilitate conservation decisions. The majority of cases were located in North and Central America, were regional in nature, and had biodiversity conservation as the primary planning objectives. Outcomes included priority-setting plans and implementation of marine reserves and other types of marine protected areas. Governments and local nongovernmental organizations led more participatory processes than national and international nongovernmental organizations. Eleven cases considered ecological criteria first, whereas 16 relied on integrated criteria (ecological plus socioeconomic data and other pragmatic considerations) to select priority areas for conservation and management action. Key tools for data integration and synthesis were expert workshops, maps, and reserve-selection algorithms (i.e., computer-based tools for priority setting and reserve design). To facilitate evaluation of success, future documentation of marine conservation planning cases should include a standard set of ecological, social, economic, and institutional elements. To develop standards for effective marine conservation, a more diverse set of documented cases is needed; for example, those that failed were located outside North and Central America, focused on the local geographic scale, or were motivated by objectives other than biodiversity conservation. [ABSTRACT FROM AUTHOR]

Humboldt Lake, a hypertrophic prairie lake typical of many found on the Great Plains of North America, is usually ice-covered from early November to about mid-May. The lake is an important recreational fishery, now mainly stocked with walleye. It has a high potential risk of experiencing fish kills because of the very large cyanobacterial blooms that develop in it, the high rates of algal and bacterial production and the high concentrations of ammonia (NH3-N) and dissolved organic matter. Following the collapse of cyanobacterial blooms, shallow prairie lakes are known to undergo periods of anoxia that can lead to summer fish kills. In some of the lakes, anoxia forms during the long period of ice cover, causing winter fish kills. Two years of seasonal and diel data (total phosphorus, dissolved oxygen (DO), NH3-N and chlorophyll- a concentrations, and bacterial production) were analysed in this study to assess why significant fish kills did not occur during this period or during the ≈ 30 years of records from Saskatchewan Environment. Humboldt Lake did not become anaerobic, either following the collapse of the cyanobacterial bloom or under ice cover, indicating that the oxygen (O2) influx (strong mixing) and production processes were greater than the microbial and chemical O2 demands, both over seasonal and diel time scales. Several published risk threshold criteria to predict the probability of summer and/or winter fish kills were applied in this study. The threshold criteria of maximum summer chlorophyll and maximum winter NH3-N concentrations indicated that a summer fish kill was unlikely to occur in this hypertrophic prairie lake, provided its water quality remained similar to that during this study. Similarly, the threshold criteria of initial DO storage before ice cover and the rate of O2 depletion under ice cover also indicated a winter fish kill was unlikely. However, recent development in the watershed might have resulted in significant water quality deterioration and the winter fish kill that occurred in 2005. [ABSTRACT FROM AUTHOR]

Text․Knowledge of the natal origins of individual birds could provide valuable information for waterfowl conservation and harvest management programs. We used stable isotopes to differentiate birds from major western North America production areas, thereby providing a means of elucidating the natal origins of waterfowl. We used a multi-isotope approach (δ34S, δ2H, δ13C, δ15N) to determine if ducks originating from different geographic areas had unambiguous multi-isotopic signatures. During 1999-2001 we took secondary feathers from prefledged mallard (Anas platyrhynchos) and northern pintail (A. acuta) ducklings from 52 sites in western North America (n=284). Ducklings from Alaska, northern Canada (YT, NWT), the Prairies (AB, SK, MB, MT, ND, SD), and California could be distinguished based upon their feather isotope values. Geographic patterns in feather isotopes were related to natural gradients produced by biogeochemical cycles and anthropogenic factors such as agrochemical usage. Stable isotopes are naturally occurring markers that may be a useful tool in the effective management of waterfowl populations. [ABSTRACT FROM AUTHOR]

1. Supplementary winter feeding of game animals, and particularly deer, is a common practice throughout northern (continental) Europe and parts of North America. Feeding is normally associated with maintaining high densities of animals for hunting, in terms of: (i) maintaining or increasing body weights and condition overwinter; (ii) improving reproductive performance and fertility; (iii) increasing overwinter survival; and (iv) reducing levels of damage caused to agriculture and forestry or the natural heritage. We consider the balance of evidence on the effectiveness of winter feeding of red deerCervus elaphusin achieving these objectives. Where that evidence is equivocal, we attempt to reconcile apparent contradictions to evaluate the circumstances under which winter feeding may or may not be effective.2. In general, feeding of red deer on open range appears to have relatively little effect on body weights or fecundity. Effects on increasing antler size and quality are variable and seem to depend on the degree to which animals may be mineral limited on native range. Effects on survival are similarly ambiguous. It is apparent, however, that to be effective in reducing mortality, any supplementation is required early in the season and not simply when heavy mortalities are already being experienced. If provision of supplementary foods is delayed until animals are perceived already to be in poor condition, such feeding may have little effect.3. One of the primary goals of winter feeding in both Europe and the USA has become the prevention of environmental damage, particularly damage to commercial and native forests, while maintaining deer populations at densities suitable for hunting. Again, empirical evidence for effectiveness in this regard is inconclusive, with some studies showing a decrease in damage caused, some showing no effect and others showing a significant increase in local impact.4. There are equally a number of problems associated with the provision of supplementary feeds overwinter. Those animals which come to the feeding stations may develop a reliance on the food supplement provided, reducing intake of natural forages to near zero; where feed provided is less than 100% of daily requirement, such animals may regularly lose, rather than gain condition. Feed provision is also extremely uneven at such feeding stations; dominant stags displace younger stags and hinds from the feed provided until they have themselves finished feeding. Concentrations of high densities of animals around small feed-areas may also increase the risk of infection and lead to development of high parasite burdens.5. In an attempt to assess the current status and distribution of supplementary winter feeding in Scotland, a questionnaire was circulated to a number of individual across the country. Results of this survey are summarized and conclusions presented on the likely effectiveness of current feeding practices in achieving their aims. [ABSTRACT FROM AUTHOR]

Deals with a study which evaluated the use of the North American Breeding Bird Survey (BBS) to meet information needs for conservation planning in bird conservation regions. Background on BBS; Methods; Results; Discussion; Implications for wildlife management.