Setting aside habitat is a common strategy to maintain viable wildlife populations, but underlying assumptions or effectiveness are rarely evaluated. The Tongass National Forest prioritized habitat management for sensitive species in Southeast Alaska's rainforest, and standards and guidelines were established for northern goshawks (Accipiter gentilis). I used guidelines from other portions of its range and data from Southeast Alaska, USA, to evaluate the conservation strategy. I used published data and nests from this study to define choice habitats; published juvenile movements and female use areas were used to estimate an “average” post-fledging area and female breeding range, respectively. I used nest-tree locations (n = 136) to delineate corresponding virtual post-fledging areas and female home ranges, within which I calculated acreage of 4 cover-type and 4 land-use categories. About 30% of nests had >51% of post-fledging areas in choice habitat; 60% of nests had >51% in unsecure (unprotected from development) land-use designations, whereas 16% had >51% in a protected old-growth designation. The female range was similar to post-fledging areas, but the proportions predominantly (>75%) available for development (land use that modifies landscapes) or with 26–50% of total area in choice habitat were larger than post-fledging areas, and half as many nests had >51% of area in choice habitat. Among cover types, choice habitat averaged 39.4% of the post-fledging area. These findings increase uncertainty about conservation measures contributing sufficient habitat to sustain well-distributed, viable populations of northern goshawks throughout Southeast Alaska and demonstrate the need and feasibility of evaluating assumptions of conservation plans. © 2013 The Wildlife Society.

With >70% of the United States held in private ownership, land-use decisions of landowners will ultimately dictate the future of bird conservation in North America. However, land-use objectives of landowners vary considerably and present opportunities and challenges for bird conservationists. Innovative strategies incorporating proactive approaches to address educational, financial, social, and economic needs of landowners are required to garner participation in conservation programs and practices to create or enhance bird habitat on privately owned working lands. Farm Bill conservation programs and practices provide unprecedented opportunities to facilitate bird conservation at regional and national scales and frequently serve as the primary vehicle for many non-governmental organizations to accomplish their bird conservation goals. We identify current challenges and opportunities for bird conservation on private lands and present 4 case studies whereby partnerships with federal agencies, mainly the U.S. Department of Agriculture's Natural Resources Conservation Service, have proven successful in eliciting positive, measurable outcomes to bird conservation efforts on private lands spanning many North American physiographic regions. The future of bird conservation will increasingly rely upon the ability of federal agencies to prioritize and allocate additional resources to deliver bird conservation programs on private lands and a greater awareness by conservationists of the role of economics in the decision-making process of landowners. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

Riparian zones are important to bats, which use them for foraging, roosting, and drinking. To predict effects of timber harvests in riparian areas on bats, more information is needed on the functional width of riparian zones for bats, and how bats respond to forest removal near small perennial streams. From May to August (2004–2007), we studied bat presence and activity in 1 unharvested site and 3 harvested sites with different riparian-buffer sizes (0 m, 10 m, and 30 m) in the southern Appalachian Mountains of the United States. We measured activity at 3 distances from the stream in each site (0 m, stream; 23 m, mid; and 46 m, far), classified bat calls by phonic group, and tested the effect of harvest on overall activity, detection, and naïve occupancy rates for 4 phonic groups. Pre-harvest activity was higher at the far versus stream or mid positions. Position, harvest, and interactions affected post-harvest change in activity in the treatment sites. Pre- and post-harvest activity was similar at all positions in the 30-m site. Activity increased significantly in the 0-m and 10-m sites, likely due to the presence of edge after harvest. Detection probabilities were higher post-harvest for larger bats and occupancy of 0-m and 10-m sites was higher post-harvest for all phonic groups except Myotis. Post-harvest responses suggest that the functional width of riparian zones in our study area is ≥10 m. This study is the first to test the effects of harvesting on use of riparian forests by bats; further long-term landscape-scale studies are needed. © 2013 The Wildlife Society.

Collecting blood samples is an important aspect of wildlife studies where data on physiological parameters are required. To avoid stress to the test animals and its potential influence on the test parameters, minimally invasive blood sampling offers numerous advantages. Here, we describe using the African tsetse fly (Glossina brevipalpis) to sample blood from meerkats (Suricata suricatta) habituated to human presence. Prior to the experiments, test animals were trained with positive reinforcement to tolerate a box that enclosed the insects being attached to their neck. This method allows drawing blood samples at defined points of time and from specific individuals during captive studies. Additionally, because it presents the first example of an African haematophagous insect suitable for sampling blood, African field studies might benefit from this minimally invasive blood-sampling technique without the risk of importing potentially invasive species. © 2013 The Wildlife Society.

The reconstruction of 90.6 km of U.S. Highway 93 from Evaro to Polson, Montana, USA, includes 41 wildlife crossing structures and 13.4 km of road with wildlife fencing. These measures are aimed at reducing wildlife–vehicle collisions and increasing human safety, while allowing wildlife to traverse the landscape. In the fenced road sections, gaps in the fence for side roads are mitigated by wildlife guards (similar to cattle guards). We monitored wildlife movements with cameras for 2 years from mid-July 2008 to mid-July 2010 at 2 wildlife guards and in 1 large crossing structure adjacent to one of the wildlife guards. We investigated how effective these wildlife guards were as a barrier to deer (Odocoileus spp.), black bear (Ursus americanus), and coyotes (Canis latrans). We also compared movements across a wildlife guard with movements through an adjacent crossing structure. The wildlife guards were ≥85% effective in keeping deer from accessing the road and 93.5% of deer used the crossing structure instead of the adjacent wildlife guard when crossing the road. The wildlife guards were less effective in keeping black bear and coyotes from accessing the road (33–55%). However, all black bears and 94.7% of coyotes used the crossing structure instead of the adjacent wildlife guard when crossing the road. Though the wildlife guards were not an absolute barrier to these species, the results indicate wildlife guards are a substantial barrier to deer and can be considered effective in mitigating gaps in a fence at access roads for these species. © 2013 The Wildlife Society

The Yellowstone ecosystem is a hotbed of environmental issues and conflicts such as endangered species management. The Yellowstone grizzly bear (Ursus arctos horribilis) delisting debate illustrates how rhetoric can contribute to fragmentation and polarization among stakeholders engaged in endangered species conflicts. The partisan view of the grizzly ideograph, and what it represented, created impediments to conflict management (e.g., mistrust and development of and/or belief in stereotypes). The debate coalesced as the U.S. Fish and Wildlife Service began proceedings to delist the Yellowstone population from the endangered species list in 2005. Our objective was to use a rhetorical analysis of the Internet-based debate to identify strategies used by disputants in conflicts over the Endangered Species Act. By analyzing web-based stakeholder texts from 1998 through 2009, we found that rhetoric about grizzly bears fell into three main categories of rhetorical appeal: authority, ethics, and identity. Arguments relying on these appeals contributed to destructive communication amongst stakeholders. Rhetorical strategies served to clearly define stakeholder belief systems and clarify exclusionary practices. We found as an emerging theme that perspectives toward climate change influenced perception of grizzly delisting (e.g., climate change influences grizzly bear food availability). The Endangered Species Act's lack of directives regarding anthropogenic climate change further complicated the debate. We demonstrated how rhetorical analyses can reveal disputants' preferred social control frameworks. This provides important information to managers seeking to promote common ground between otherwise conflicted stakeholders that leads to legitimate and lasting policy decisions. © 2013 The Wildlife Society.

Ponderosa pine (Pinus ponderosa) forests in western North America provide habitat for numerous cavity-using wildlife species that often select large-diameter snags for nesting and roosting. Yet large snags are often removed for their commercial and firewood values. Consequently we evaluated effects of human access on snag densities and diameter-class distributions at nine locations in ponderosa pine forests throughout the interior western United States. We found no relationship between small-diameter (23–50 cm diam breast ht [dbh]) snags and human access measures (i.e., road density, distance to nearest town, and topography). However, large-snag (≥50 cm dbh) density was best predicted by road density, which suggested a decline, on average, of 0.7 large snags/ha for every km of road/km². Most locations had relatively high densities of small-diameter snags (<23 cm dbh) and diminishing density as diameter class increased. Idaho and Colorado study locations had higher snag densities in the largest diameter classes compared with remaining locations. These locations experienced minimal commercial timber harvest, were situated far from towns, and had few or no roads. Persistence of large-diameter snags and adequate snag densities for wildlife requires consideration of human access characteristics at coarse spatial scales. Snag management guidelines may need to incorporate these measures and focus more on retention of large-diameter snags than minimum density targets. © 2013 The Wildlife Society.

Forests are potential sources for a wide range of alternative fuels, which could reduce dependency on fossil fuels and carbon emissions, but sustainability of producing biofuels from forests has not been well-studied. Therefore, we investigated effects of woody biomass harvest, intercropping perennial grasses, and combinations of these treatments on herpetofauna in loblolly pine (Pinus taeda) plantations in a randomized and replicated field experiment in eastern North Carolina, USA. We sampled amphibians and small reptiles with drift fence arrays from April to July during 1 and 2 years after treatment establishment. We had 425 captures of 15 species of herpetofauna across the 2 sampling seasons, but did not observe large general effects of biomass removal or planting of switchgrass (Panicum virgatum) in pine plantations on detection, diversity, or relative abundance. However, planned contrasts indicated Simpson's index of diversity was greater in plots managed for switchgrass only compared with pine plantations during year 2, and that captures of southern toads (Anaxyrus terrestris) were less common in switchgrass plots than in pine plantations intercropped with switchgrass. Neither intercropping switchgrass with pine nor removal of harvest residuals caused herpetofauna diversity or abundance of common species to differ from traditional plantation management during the first 2 years following treatment establishment. With the exception of switchgrass-only plots, which had lower herpetofauna species evenness, the potential practices we considered for biofuels production are unlikely to have short-term effects on herpetofauna relative to traditional pine management. Future research should monitor herpetofauna through succession and consider landscape-scale effects and other potential feedstock sources. © 2013 The Wildlife Society.

In the Unicoi Mountains of southwestern North Carolina, USA, a 2 lane scenic byway created a barrier to dispersal for the federally endangered Carolina northern flying squirrel (Glaucomys sabrinus coloratus). Unable to glide across the road, squirrels in the divided subpopulations faced reduced access to mates, den sites, and foraging grounds. We installed 3 pairs of modified wooden utility poles as crossing structures to enable gliding over the road in both directions. Using wildlife cameras, we monitored use of the crossing poles by northern flying squirrels for 15 months. Additionally, we tracked movements of 4 radiocollared northern flying squirrels between habitat patches and checked nest boxes for evidence of squirrels crossing the road. Cameras recorded 5 still images and 25 videos of northern flying squirrels on the crossing poles, with flying squirrels leaping across the road in 56% of videos. Crossings increased from 0 crossings in a previous study to 14 crossings in this study. For the first time since crossing-pole installation, squirrels used dens on the opposite side of the road from where they were initially captured and tagged. We believe that these structure-assisted road crossings in the Unicois are the first observed in a North American gliding mammal. Although northern flying squirrels used crossing poles to glide over a rural, low traffic, 2-lane road, further research should be conducted to determine whether this technique is applicable to different road types and other types of linear barriers in North America. © 2013 The Wildlife Society.

Concerns regarding the potential negative impacts of regulated furbearer trapping to reintroduced Mexican gray wolves (Canis lupus baileyi), led to an executive order prohibiting trapping in the New Mexico, USA, portion of the Blue Range Wolf Recovery Area. This ban was to last for 6 months and required an evaluation of the risk posed to wolves by traps and snares legally permitted in New Mexico. We reviewed potential threats to wolves in the Blue Range Wolf Recovery Area, including threats associated with regulated furbearer trapping. One hundred Mexican gray wolf mortalities have been documented during the reintroduction effort (1998–2011). Of those mortalities with a known cause, >81% were human-caused resulting from illegal shooting (n = 43), vehicle collisions (n = 14), lethal removal by the United States Fish and Wildlife Service (USFWS; n = 12), non-project-related trapping (n = 2), project-related trapping (n = 1), and legal shooting by the public (n = 1). Ten wolves died due to unknown causes. The remaining 17 mortalities were a result of natural causes (e.g., starvation, disease). An additional 23 wolves were permanently, but non-lethally, removed from the wild by the USFWS. Of 13 trapping incidents in New Mexico that involved non-project trappers (i.e., trappers not associated with USFWS or U.S. Department of Agriculture-Wildlife Services), 7 incidents are known to have resulted in injuries to wolves: 2 wolves sustained injuries severe enough to result in leg amputations and 2 additional wolves died as a result of injuries sustained. Foothold traps with rubber-padded jaws and properly set snares may reduce trap-related injuries to Mexican gray wolves; however, impacts caused by trapping are overshadowed by other anthropogenic impacts (e.g., illegal shooting, non-lethal permanent removal, and vehicle collisions). © 2013 The Wildlife Society.

The jaguarundi (Puma yagouaroundi) is a Neotropical felid that ranges from northern Mexico to South America. The population trend for jaguarundis is declining, yet much remains unknown about their ecology. We live-trapped 11 jaguarundis during 1991–2004 in Tamaulipas, Mexico, and we collected blood for genetic analyses. Our objectives were to 1) estimate neutral diversity using microsatellite and mitochondrial (mtDNA) markers, 2) estimate potentially adaptive diversity in coat coloration via the melanocortin-1 receptor gene (MC1R), and 3) provide recommendations on the use of genetic markers for noninvasive studies. We observed moderate levels of heterozygosity (H_E = 0.49, SD = 0.22) and number of alleles (A = 4.00, SD = 1.65) at 12 feline microsatellite loci. The probability of identifying 2 different jaguarundis as the same individual was low using only 4–7 loci (P_(ID) < 0.001 and P_(ID)sib < 0.01, respectively). We observed one mtDNA haplotype, indicating no mtDNA diversity. However, we documented diversity with the MC1R assay. The frequency of the melanistic mutation (gray phenotype) was 0.33, whereas, the frequency was 0.67 for the ancestral allele (red phenotype). Microsatellite diversity of our sampled jaguarundis was less than that of sympatric populations of ocelots (Leopardus pardalis) in Tamaulipas; however, mtDNA diversity was much lower. The frequency of the melanistic mutation was lower in our sample than was previously reported in captive jaguarundis. Our microsatellite loci provided adequate diversity to implement noninvasive genetic tools to better understand the ecology of the elusive jaguarundi. To our knowledge, this work is the first genetic evaluation of wild jaguarundis and provides baseline information for future research and conservation. © 2013 The Wildlife Society.

The parcelization of exurban landscapes creates a matrix of intermediately sized and privately managed land parcels, presenting a unique challenge to wildlife managers. During 2010–2011, we studied the correlates between land parcelization, deer density, and hunting patterns in exurban northwestern Virginia, USA. We estimated October deer densities (no. deer/km²) and conducted landowner surveys of deer harvest in 13 study blocks of mean size 34.8 km². The extent of parcelization varied between study blocks; mean parcel size ranged from 2.00 ha to 26.12 ha. We used distance-sampling techniques to survey pre-harvest deer densities in each section, with estimated densities ranging from 9.4 deer/km² to 30.1 deer/km². We quantified deer harvest through calculations of harvest density and the percentage of land hunted. As parcel size increased, the percentage of land hunted increased. Harvest densities reported by landowners, however, remained constant with the exception of 2.0–4.0-ha parcels, which had higher harvest densities than 60.8–161.8-ha parcels. We used linear regression analysis to model the response of deer density (natural log) to landscape metrics, and the best-fit model predicted deer density from mean parcel size with equivalent models including habitat with mean parcel size. Our results suggest that development processes that subdivide rural lands can significantly increase deer populations. The mechanism for this increase may be restricted hunter access to smaller property parcels and-or increased probability of deer refuges nearby. © 2013 The Wildlife Society.

Current waterfowl populations provide liberal hunting seasons, but waterfowl hunter numbers have declined since the mid-1990s. We hypothesized that trends in waterfowl hunter numbers, as indicated by Federal Migratory Bird Hunting Conservation Stamp (duck stamp) sales, have become independent of breeding duck populations, and we assess the impacts on habitat conservation. The relationship between duck breeding populations and duck stamp sales changed between 1955–1994 (r = 0.81) and 1995–2008 (r = 0.29). Based on the 1955–1994 relationship between total duck breeding population and duck stamp sales, about 600,000 fewer duck stamps than expected were sold annually during 1995–2008. This equates to a loss of US$126 million in gross revenue and from 42,500 to 80,900 fewer hectares of wetland and upland hectares protected. The current relationship between duck breeding population and duck stamp sales suggests future estimates of waterfowl hunters will decrease below 1 million when the breeding population declines below 32 million. Assuming current trends, expected losses of duck stamp revenues may result in an additional 2,800–13,900 unprotected ha/year if the duck breeding population declines to historical lows. Development and implementation of programs and policies that maintain or increase participation in waterfowl hunting will assist in habitat conservation efforts and continue waterfowl hunting traditions. © 2013 The Wildlife Society.

In Oregon, USA, bobcats on either side of the Cascade Mountain Range are recognized as distinct subspecies, with Lynx rufus fasciatus west and Lynx rufus pallescens east of the Cascades. These subspecies are currently managed for harvest as separate populations primarily because of substantial differences in regional pelt values. We used genetic data to determine whether bobcats in Oregon are subdivided into genetically discernible populations that support current regional management regulations. We collected 250 tissue samples from 12 a priori sampling districts, and generated data from 15 microsatellite markers and approximately 1 kB of mtDNA sequence. Results of clustering analyses based on the microsatellite data indicated strong support for the presence of 2 genetic populations, generally corresponding to the 2 subspecies. Analysis of molecular variance (AMOVA) indicated significant structure between the east and west regions, which accounted for 1.7% of the total variation in microsatellites. AMOVA based on the mtDNA sequences indicated significant structure between regions, accounting for 12.8% of the mtDNA variation. With both microsatellite and mtDNA data, we observed a significant pattern of isolation-by-distance, whereby geographically proximate sampling districts were more genetically similar than were more distant districts. We identified 21 putative migrants, individuals with genotypes more likely to have originated from the opposite region, showing that the Cascade Mountain Range apparently is not an absolute barrier to gene flow. Given the potential for differential harvest effort by region based on differences in pelt values and bobcat densities, and the vulnerability of bobcats to harvest, our results support the current management framework. © 2013 The Wildlife Society.

Wind-energy generation is expanding globally, largely in response to climate change predictions, in an attempt to reduce our dependency on fossil fuels. The increasing demand for locations with suitable wind resource places pressure on bird species and sites of conservation importance. Our understanding of the effects of wind-energy generation on birds is growing, but ambitious targets for wind-energy production mean that we need to apply best available information in smarter ways now, refining our approaches as evidence accrues. This applies especially to the offshore “windrush,” which is taking place in Europe, notably the United Kingdom, which currently leads the world in installed capacity offshore. This paper presents UK experience and European studies, onshore and offshore, to consider lessons learned, especially in view of the fledgling offshore industry in the USA. © 2013 The Wildlife Society.

Estimates of bird and bat fatalities are often made at wind-energy projects to assess impacts by comparing them with other fatality estimates. Many fatality estimates have been made across North America, but they have varied greatly in field and analytical methods, monitoring duration, and in the size and height of the wind turbines monitored for fatalities, and few benefited from scientific peer review. To improve comparability among estimates, I reviewed available reports of fatality monitoring at wind-energy projects throughout North America, and I applied a common estimator and 3 adjustment factors to data collected from these reports. To adjust fatality estimates for proportions of carcasses not found during routine monitoring, I used national averages from hundreds of carcass placement trials intended to characterize scavenger removal and searcher detection rates, and I relied on patterns of carcass distance from wind turbines to develop an adjustment for variation in maximum search radius around wind turbines mounted on various tower heights. Adjusted fatality rates correlated inversely with wind-turbine size for all raptors as a group across the United States, and for all birds as a group within the Altamont Pass Wind Resource Area, California. I estimated 888,000 bat and 573,000 bird fatalities/year (including 83,000 raptor fatalities) at 51,630 megawatt (MW) of installed wind-energy capacity in the United States in 2012. As wind energy continues to expand, there is urgent need to improve fatality monitoring methods, especially in the implementation of detection trials, which should be more realistically incorporated into routine monitoring. © 2013 The Wildlife Society

With the expansion of wind-energy generation, there is a growing need to develop accurate and efficient methods to detect bat casualties resulting from turbine collision and barotrauma. We conducted a formal blinded trial comparing the abilities of search dogs and human observers to locate bat carcasses. Dogs located 73% (46/63) of bats, whereas humans found 20% (12/60). We therefore recommend search dogs as an effective means of monitoring bat fatalities, particularly when a high degree of search accuracy is important. This includes surveys for rare species, or cases where searches are limited in extent or duration, because the application of correction factors is problematic where very few or no casualties are found. The dogs averaged 40 min to complete a survey, which was <25% of the time taken by humans. At large sites, the high initial set-up costs for search dogs can therefore be offset by the increased number of surveys that can be conducted within a given time. However, care must be taken with the selection and training of the dogs and handlers to produce consistent results. To allow fatality rates to be estimated from the number of casualties located, it is essential that assessments of the accuracy of the dog–handler team are made at each site. © 2013 The Wildlife Society.

Worldwide expansion in wind-energy generation has raised concerns about bird collisions—in particular, protected species. Bird collision studies are common in Europe and USA, but none had been done in Japan to date. We studied bird fatalities at 42 turbines (52.8 MW) in Tomamae, northern Hokkaido, Japan. For 17 months from July 2007 to November 2008, we performed 24 fatality surveys at an average 21-day interval and ≤100 m from the wind turbines. We found 52 fatalities, including 4 white-tailed eagles (Haliaeetus albicilla). Our estimate of the adjusted annual mortality at Tomamae, which used a modified equation to factor in the complex topography and dense vegetation spread generically over Japan, was 2.20 bird fatalities/MW/year and 0.36 raptor fatalities/MW/year. Bird utilization rates explained most of the variation in fatality rates among species and among locations. The highest fatality rates occurred at the turbines on a costal cliff where the rotor zones of wind turbines overlapped the frequent flight paths of large birds. The development of generalized models can be useful for predicting the impacts of other wind projects on birds, with the exceptions of high-risk situations. However, more surveys of fatality rates and utilization rates are required at this and additional study sites, and over a longer period with shorter search intervals, to develop predictive models of bird collisions with general applicability. © 2013 The Wildlife Society.

Understanding the interaction between eagles and wind farms is essential for the development of strategies to minimize collision risk, and to quantify avoidance rates for collision risk modeling. The purpose of our study was to measure the avoidance rates of Tasmanian wedge-tailed eagles (Aquila audax fleayi) and white-bellied sea-eagles (Haliaeetus leucogaster) using a new method, and to examine factors affecting these rates. We conducted eagle surveys at the Musselroe Wind Farm (undeveloped and used as a control); Studland Bay Wind Farm during commissioning and operational stages; and Bluff Point Wind Farm during the operational stage, all in northern Tasmania, Australia. Observers documented flight tracks and behavior of eagles over 875 days during the period 2006–2008. Both species demonstrated a distinct avoidance of the turbines, preferring to fly midway between them. Avoidance rates were 81%–97%, and differed significantly between species and sites, with white-bellied sea-eagles avoiding at a higher rate than wedge-tailed eagles. Eagles at Bluff Point had a higher avoidance rate than those at Studland Bay, even though the sites were only 3 km apart. Both species altered their avoidance rates in response to stages in the wind-farm development, but only the wedge-tailed eagle altered its rate in response to weather conditions, demonstrating a higher avoidance rate during wet and windy conditions. Our study found that the interaction of eagles and wind turbines is complex, which highlights the need for further study of avoidance rates in species at different sites. © 2013 The Wildlife Society.

We describe the model of Biosis Propriety Limited for quantifying potential risk to birds of collisions with wind turbines. The description follows the sequence of the model's processes from input parameters, through modules of the model itself. Aspects of the model that differentiate it from similar models are the primary focus of the description. These include its capacity to evaluate risk for multi-directional flights by its calculation of a mean presented area of a turbine; its use of bird flight data to determine annual flux of movements; a mathematical solution to a typical number of turbines that might be encountered in a given bird flight; capacity to assess wind-farm configurations ranging from turbines scattered in the landscape to linear rows of turbines; and the option of assigning different avoidance rates to structural elements of turbines that pose more or less risk. We also integrate estimates of the population of birds at risk with data for numbers of their flights to predict a number of individual birds that are at risk of collision. Our model has been widely applied in assessments of potential wind-energy developments in Australia. We provide a case history of the model's application to 2 eagle species and its performance relative to empirical experience of collisions by those species. © 2013 The Wildlife Society.

Evidence is increasing of bird mortality due to large-scale wind-energy development. Soaring raptors, such as the white-tailed eagle (Haliaeetus albicilla), have proven particularly vulnerable to collisions. In this study, we compared white-tailed eagle flight behavior both inside and outside of the Smøla wind-power plant on coastal Central Norway. During the eagle breeding period (mid-Mar–end May 2008), we collected data on flight activity (directional flight, social behavior, and soaring) and flight altitude (below, within, and above the rotor-swept zone [RSZ]) at 12 vantage points; 6 within the wind-power plant and 6 outside (control area). We found that white-tailed eagles did not show any clear avoidance flight responses to the wind turbines. Hence, we found no significant differences in the total amount of flight activity within and outside the power-plant area. However, we found less flight activity among adults than among subadults within the power plant compared with the control area. We also found a slightly increased probability of flight activity in the RSZ within the power plant, which obviously may increase the risk of collision with wind turbines. Our findings may help explain the relatively high mortality rate of white-tailed eagles in the wind-power-plant area and the recorded peak in eagle fatalities during the breeding season. © 2013 The Wildlife Society.

On average, 7.8 white-tailed eagles (Haliaeetus albicilla) collide with wind turbines annually at the operating wind-power plant on the island of Smøla off the coast of central Norway. To better understand the impact of this wind-power plant on white-tailed eagles, we investigated how habitat utilization affected displacement effects. We collected data on habitat utilization in non-territorial subadult white-tailed eagles using global positioning system satellite telemetry (2004–2009). From these data, we estimated utilization distributions using the Brownian bridge movement model and analyzed them using Resource Utilization Functions. Home ranges were circa 10–30% smaller for subadults hatched on skerries and islets farther from the wind-power plant, and tended to be circa 40% larger during spring. Shallow sea, skerries, and islets were utilized extensively, as was marsh, heathland, and forest on the main island of Smøla. We noted lower selectivity for arable land and higher levels of differentiation in utilization among individuals for forest and islets. Females also had a nearly 4 times higher between-individual variation, which was likely due to long-ranging excursions. The within- and between-individual variation among seasons showed an annual pattern, with increasing between-individual variation toward summer. Displacement (indicated by an overall 40% proportional reduction in utilization) was more pronounced in the birds' second and third calendar year compared with their first calendar year, and during autumn–winter. Reduced displacement during spring coincides with the white-tailed eagle pre-breeding period with increased flight activity. This may, in part, explain increased collision risk during spring. Possible displacement effects in white-tailed eagles may be avoided by siting wind-power plants farther inland or offshore. © 2013 Wiley Periodicals, Inc.

Environmental impact assessment allows for compensation of environmental injuries in the form of resource-based restoration projects. Given that compensation is a desired policy at a given site, this study suggests an interdisciplinary scaling method (Resource Equivalency Analysis) that relies on a non-monetary bird-year metric to quantify and value the impact on human welfare from ecosystem service loss. The lost value associated with white-tailed eagle (Haliaeetus albicilla) turbine collisions at the Smøla wind-power plant (debit) in central Norway is compensated through white-tailed eagle electrocution-prevention measures at nearby power lines (credit), scaled using the same bird-year metric. We found that 172 actual and projected white-tailed eagle turbine collisions (2005–2027) led to a debit of 3,454 discounted bird-years, which captures lost life expectancy discounted to present value. Field searches indicated that annual white-tailed eagle electrocution mortality per electric distribution pole (or pylon) at Smøla ranges from 0.002 to 0.014 (2009–2011). We suggest that retrofitting between 348 and 2,209 pylons at a present-value cost of US$1.2–7.9 million (2011 at 3%) will provide equivalent value and thus compensate the public for their welfare losses. Improved electrocution probability models will improve cost-effectiveness of retrofitting as a compensatory measure. Although Resource Equivalency Analysis may provide an approach for scaling a biodiversity offset, it cannot address the inevitable environmental trade-offs required in assessing the social profitability of choosing to compensate at a particular site. © 2013 The Wildlife Society.

The changing demographics of rural landowners have the potential to affect wildlife management on private land and therefore, there is a need to determine what factors influence landowner participation in wildlife management. We surveyed 1,368 North Carolina, USA, private landowners to determine socio-demographic factors predicting participation in a variety of wildlife management practices. Wildlife management practices most commonly implemented by landowners were providing supplemental feed (21.8%), mowing to improve habitat (16.2%), erecting nesting boxes (14.7%), and planting food plots (14.6%). Ecologically valuable management activities such as prescribed burning (2.3%) were among the least practiced. Hunting or having a family member that hunted was the most consistent predictor of participation in wildlife management practices. Landowners who hunted, resided on their property, were younger and were male were more likely to implement wildlife management practices than their counterparts. Resident landowners, especially those who hunt, may be the most receptive to outreach efforts promoting wildlife habitat management on private lands. Our results indicate outreach efforts should target habitat management practices with longer term wildlife benefits (e.g., prescribed fire, controlling invasive plants), because practices with immediate short-term benefits (e.g., food plots, supplemental feeding, mowing) are currently 3–4 times more prevalent. © 2012 The Wildlife Society.

Female mallards (Anas platyrhynchos) emit a diverse repertoire of vocalizations. Duck hunters and callers mimic these vocalizations using artificial calls made from wood or plastic. The extent to which humans can mimic live mallards using artificial calls is unknown. We compared acoustic features of field recordings of the decrescendo calls of wild female mallards with those of duck callers. A panel of 38 duck callers used artificial calls equipped with single and double reeds that were made of 7 species of hardwoods and cast acrylic. We found that cocobolo (Dalbergia retusa), osage orange (Maclura pomifera), pecan (Carya sp.), acrylic, and bocote (Cordia alliodora) calls with double reeds produced notes acoustically most similar to female mallard decrescendos. We recommend that duck hunters and callers use calls made of acrylic or harder wood species, recognizing that double reed calls generally out-performed single reed calls in this study. We recommend that similar studies be conducted for other types of game calls, and we recommend additional future research to determine whether use of such calls influences mallard harvest and hunter satisfaction. © 2013 The Wildlife Society.

We used structured decision-making to develop a 2-part framework to assist managers in the proactive management of disease outbreaks in Montana, USA. The first part of the framework is a model to estimate the probability of disease outbreak given field observations available to managers. The second part of the framework is decision analysis that evaluates likely outcomes of management alternatives based on the estimated probability of disease outbreak, and applies managers' values for different objectives to indicate a preferred management strategy. We used pneumonia in bighorn sheep (Ovis canadensis) as a case study for our approach, applying it to 2 populations in Montana that differed in their likelihood of a pneumonia outbreak. The framework provided credible predictions of both probability of disease outbreaks, as well as biological and monetary consequences of management actions. The structured decision-making approach to this problem was valuable for defining the challenges of disease management in a decentralized agency where decisions are generally made at the local level in cooperation with stakeholders. Our approach provides local managers with the ability to tailor management planning for disease outbreaks to local conditions. Further work is needed to refine our disease risk models and decision analysis, including robust prediction of disease outbreaks and improved assessment of management alternatives. © The Wildlife Society, 2012

Communication programs are a tool available to wildlife managers for managing risks associated with wildlife diseases such as bovine tuberculosis (TB). Evaluating these communication efforts is vital for successful disease management planning; yet, systematic evaluations of wildlife disease-related communication programs are lacking. To this end, we analyzed the content of 41 print and electronic TB risk communication materials (e.g., brochures, handouts, websites) available to stakeholders in Michigan and Minnesota, USA, during April 2010 to 1) describe and compare the materials; 2) make data-based recommendations to improve existing messages; and 3) highlight the ability of the extended parallel process model (EPPM), a well-known health communication theory, to serve as a framework for evaluation of wildlife disease issues. All message components central to the EPPM were identified in our sample of TB risk communication materials. More than 80% of materials promoted ≥1 behaviors believed to reduce the risks of TB transmission among and between wildlife and livestock in Michigan and Minnesota. Messages conveying severity and susceptibility of TB-related risks were present in 73% and 56% of the materials, respectively; whereas, efficacy messages promoting the ease and effectiveness of recommended behaviors were far less prevalent. Results provide insights for future TB and wildlife disease-related risk communication efforts (e.g., design messages that enhance stakeholder perceptions of efficacy) and demonstrate the utility of the EPPM as a framework to evaluate risk communication materials and messages for wildlife disease-related stakeholders. © 2013 The Wildlife Society

Emotions play a key role in our experiences with and our responses to wildlife. We examined the effectiveness of situational and emotional variables in predicting acceptability of management actions for wolves (Canis lupus) in the Greater Yellowstone Ecosystem, USA. We advanced 3 hypotheses: 1) both situational and emotional variables will influence acceptability ratings; 2) emotions will explain the largest proportion of variance for the lethal management action; and 3) this pattern of findings will be the same for residents and visitors of the Greater Yellowstone Ecosystem. We obtained our data from a survey of residents living near Jackson, Wyoming (n = 604, response rate = 51%) and a survey of visitors to Grand Teton National Park (n = 596, response rate = 81%). We included 2 situational variables (i.e., location of encounter, wolf status) and 3 emotional variables (i.e., sympathy for ranchers, sympathy for wolves, anger about wolves) as independent variables. The dependent variables were acceptability ratings of non-lethal and lethal management actions. Regression analyses supported all 3 hypotheses. For both groups, situational variables accounted for between 1% and 8% of the variance in acceptability of non-lethal management actions, while emotions explained between 3% and 20%. For the lethal management action, situational variables predicted between 3% and 5% of the variance in acceptability ratings, while emotions accounted for between 41% and 49%. Although debates regarding the status of wolves are likely to continue, these findings highlight the role emotion plays in evaluating the acceptability of management actions. © 2013 The Wildlife Society.

Effective deer management must consider diverse stakeholder values. From 2006 to 2011, the Pennsylvania (USA) Game Commission implemented citizen advisory committees (CACs) to measure deer–human conflicts and tolerance for deer populations in each wildlife management unit. There was a general lack of public interest in participating in CACs. Key stakeholder groups were often absent and CACs exhibited a strong hunter bias. Although the CAC process seemed to benefit those involved, the scope was limited and likely did not represent the values and attitudes of the entire citizenry within the wildlife management unit. As a result of this CAC experience, the Pennsylvania Game Commission moved to a citizen survey in 2011 to ensure all interests are represented as the future success of deer management depends on greater understanding of the values and attitudes of every stakeholder. © The Wildlife Society, 2012

Hunting has been the primary white-tailed deer (Odocoileus virginianus) management tool for decades. Regulated hunting has been effective at meeting management objectives in rural areas, but typical logistical constraints placed on hunting in residential and urban areas can cause deer to become overabundant and incompatible with other societal interests. Deer–vehicle collisions, tick-associated diseases, and damage to residential landscape plantings are the primary reasons for implementing lethal management programs, often with objectives of <10 deer/km². There are limited data demonstrating that hunting alone in suburban landscapes can reduce densities sufficiently to result in adequate conflict resolutions or a corresponding density objective for deer. We present data from 3 controlled hunting programs in New Jersey and one in Pennsylvania, USA. Annual or periodic population estimates were conducted using aerial counts and road-based distance sampling to assess trends. Initial populations, some of which were previously subjected to regulated unorganized hunting, ranged from approximately 30–80 deer/km². From 3 years to 10 years of traditional hunting, along with organized hunting and liberalized regulations, resulted in an estimated 17–18 deer/km² at each location. These projects clearly demonstrate that a reduction in local deer densities using regulated hunting can be achieved. However, the sole use of existing regulated hunting techniques in suburban areas appears insufficient to maintain deer densities <17 deer/km² where deer are not limited by severe winter weather. Additional measures, such as sharpshooting or other strategic adjustments to regulations and policies, may be needed if long-term deer-management objectives are much below this level. © The Wildlife Society, 2012

Although wildlife biologists need reliable estimates of white-tailed deer (Odocoileus virginianus) density to facilitate management, few studies have examined distance sampling as a density estimation technique for this species. We compared direct (i.e., spotlighting from road transects) and indirect (i.e., counting pellets on randomly placed transects) distance-sampling techniques for estimating deer densities in east-central Illinois, southern Illinois, and northern Michigan (USA) during 2007–2008. Density estimates (95% CI) from indirect distance sampling for northern Michigan, east-central Illinois, and southern Illinois were 6.1–12.7 deer/km², 11.2–15.8 deer/km², and 15.4 deer/km², respectively. Density estimates from direct distance sampling for northern Michigan, east-central Illinois, and southern Illinois were 18.3–25.2 deer/km², 14.4–18.1 deer/km², and 19.0 deer/km², respectively. Although density estimates did not differ between techniques in east-central Illinois and southern Illinois, density estimates derived by direct sampling were slightly higher than those derived by indirect sampling. Estimates of density from direct distance sampling were higher than indirect distance sampling in northern Michigan. The difference in estimates among study areas may be due to landscape-specific differences in the behavioral response of deer to roads and the representativeness of road transects. In landscapes containing more agriculture, roads tend to be systematically distributed and forest edges are independent of road placement, which may explain why both distance-sampling methods provided similar results in Illinois. However, in more forested landscapes such as Michigan, roads tend to follow streams and may provide forest edges that are relatively scarce on the landscape. Deer in forested landscapes may be attracted to roadsides, resulting in higher density estimates not indicative of surrounding forested areas. Therefore, use of road transects for direct distance sampling may be more applicable in non-forested landscapes. © The Wildlife Society, 2012

Locally overabundant white-tailed deer (Odocoileus virginianus; hereafter, deer) have caused increased damage to agronomic crops across their range. Winter wheat (Triticum aestivum) is grown in >60% of the states in the United States where white-tailed deer occur. Although the effect of deer browsing on corn (Zea mays) and soybean (Glycine max) yields has been documented, research on the effect of deer browsing on winter wheat yields and quality is limited. In 2007–2009, we investigated the effect of deer browse timing and wheat type (bearded and unbearded) on yields and quality in Delaware, USA. We randomly stratified 3 treatments (i.e., no protection, protected at planting, or protected prior to heading) in 1,680 plots. After head emergence, we surveyed the plots weekly to estimate browse rates and biomass removed by deer. We harvested a 1-m² area in the middle of each plot to determine the deer impact on yield. Browsing increased in intensity as head development progressed and more browsing occurring on the unbearded wheat. Unprotected plots had 195 kg/ha greater wheat yield than did protected plots in 2007 (P = 0.08). We found no difference in wheat yield among treatments during 2008 and 2009 (P = 0.38). Bearded wheat fields had 379 kg/ha greater wheat yield during 2007 and 399 kg/ha greater yield during 2008 and 2009 than did unbearded wheat fields (P < 0.001). We also observed no difference in wheat quality among treatments or between types of wheat (P > 0.417). Our browse surveys suggested avoidance of bearded wheat but the overall browsing was not intense enough to affect yield. Our results demonstrated that white-tailed deer had no impact on wheat yield at a deer density of 15 deer/km². © 2013 The Wildlife Society.

Ketamine and xylazine are an effective chemical combination for white-tailed deer (Odocoileus virginianus) immobilization, but the effects of body condition on ketamine–xylazine efficacy have not been examined. We assessed the influence of ketamine dosage, xylazine dosage, body condition, age class, and injection site on successful adult female deer chemical immobilization. From January to March 2009–2011, we captured 87 deer (age ≥1.5 yr) in Clover traps and immobilized them using ketamine–xylazine ratios of 400 mg (n = 58) or 300 mg (n = 29) of ketamine to 100 mg of xylazine. Mean deer body mass was 67.8 kg (SD = 12.3, range = 43.0–93.0). We considered immobilization successful if deer induction was achieved ≤15 minutes from first ketamine–xylazine injection. Seventy-five percent of injected deer (81% with 400:100 mg ketamine:xylazine; 62% with 300:100 mg ketamine:xylazine) achieved successful induction. We recorded deer heart rate, respiration rate and rectal temperature at 0 minutes, 10 minutes, and 20 minutes post-induction. Comparison of 7 generalized linear models indicated that the probability of successful induction increased by about 6.7% with every 1.0 mg/kg increase in ketamine dosage and by about 0.7% with every 1-unit decrease in body-condition index. The remaining parameters did not influence the success of deer induction. Deer heart rate, respiration rate, and rectal temperature decreased over time post-induction, with >95% within reported ranges for ketamine–xylazine immobilization. We suggest that deer weighing ≤93.0 kg be injected with 5.8 mg/kg ketamine and 1.6 mg/kg xylazine to produce satisfactory induction when using similar capture methods during winter. © 2012 The Wildlife Society.

Habitat fragmentation is considered a contributing factor to declining populations of northern bobwhite (Colinus virginianus). Some population strongholds exist within large expanses of habitat; however, many regions of the species' range have become fragmented and populations therein have become nearly extirpated. Our objectives were to determine whether combined habitat management and bobwhite translocation could restore bobwhite populations in habitat patches within a fragmented landscape. We translocated 550 bobwhites to 2 sites (≥660 ha; Caldwell and Fayette counties) in the Post Oak Savannah ecoregion of Texas, USA, during 2004–2006. We compared survival, home-range size, and reproduction between translocated bobwhites in a fragmented landscape and resident bobwhites in contiguous habitat (Brooks County). Pooled over the 3-year study, translocated bobwhites had lower survival (6 Apr–15 Aug, 2004–2006; Ŝ = 0.35; n = 165 bobwhites) than did resident bobwhites (Ŝ = 0.56; n = 224 bobwhites; P < 0.001). Translocated bobwhites also had larger home ranges ( = 398.1 ha; n = 55 bobwhites) than resident bobwhites ( = 10.9 ha; n = 28 bobwhites; P = 0.003). Moreover, percent of hens nesting (95% CI = 36 ± 16.4%) and nesting rate (95% CI = 1.1 ± 0.2 nests/hen) were lower for translocated bobwhites than for resident bobwhites (79 ± 12.4% and 1.6 ± 0.3 nests/hen, respectively). Our restoration efforts were unsuccessful; relative abundance of bobwhites remained low (≤1.0 covey heard/point) on translocation sites despite intensive translocation efforts. Restoring bobwhite populations in areas with few remaining bobwhites may be beyond the realm of practical management in this fragmented ecoregion. © 2012 The Wildlife Society

The northern bobwhite (Colinus virginianus) decline has become a cause célébre of wildlife conservation during the past 2 decades. With few exceptions, current broad-scale population trends show ongoing erosion in bobwhite numbers across most of the species' range. The causes of these declines are ultimate factors exacerbated by certain proximate factors. Ultimate factors are centered on the loss and fragmentation of habitat. Proximate factors such as predation and disease also may be present. The impacts of some factors, such as climate change, remain unknown but may influence bobwhite population trajectories over the long term. Progress has occurred in bobwhite conservation efforts since 1990 and has culminated in the formation of the National Bobwhite Technical Committee and the publication of the Northern Bobwhite Conservation Initiative. The vast majority of prevailing agricultural, forestry, and to some extent rangeland land uses in the United States continue as threats to bobwhite population persistence in the foreseeable future. Land-use patterns that once sustained widespread abundance of northern bobwhite during the early 20th century clearly are past and likely never to return. Landscape features that sustain and elevate northern bobwhite populations will only be maintained as a function of purposeful management actions directed at saving and creating usable space. © The Wildlife Society, 2012

Open pine–grasslands are one of the most threatened ecological communities in the southeastern United States and provide essential habitat for many regionally declining bird species. While open pine–grassland forests have diminished, acreage of pine plantations has increased throughout the Southeast, in part because of the U.S. Department of Agriculture Farm Bill conservation programs. To understand whether fire and herbicide treatments would be effective in creating pine–grassland structure in plantations suitable for a suite of declining early successional and pine–grassland adapted species, we evaluated combined effects of selective herbicide and prescribed fire on plant and bird communities in thinned, mid-rotation pine stands established under the Conservation Reserve Program (CRP) in Mississippi, USA. Within each of the 12 replicate sites, we assigned 2 paired 8.1-ha plots to either treatment (herbicide + prescribed fire) or control in a randomized complete block design. We applied treatments during autumn and winter of 2002–2003. During 2003–2006 breeding seasons, we characterized the bird community using repeated (4–6 repetitions/yr), standardized, 10-minute point counts from which we estimated species richness, total relative abundance, total avian conservation value, and density of select species. Managed plots exhibited reduced hardwood midstory and a greater abundance of grasses and forbs in the ground layer. Although avian species richness and total relative abundance were similar in treatment and control stands, we observed a shift in the bird community from closed-canopy forest species to early successional and pine–grassland adapted species, many of which are experiencing population declines. We recommend thinning, hardwood midstory control, and prescribed burning within CRP pine plantations to provide habitat for a suite of regionally declining bird species. © 2012 The Wildlife Society.

In New York State, USA, the abundance of ruffed grouse (Bonasa umbellus) has declined >75% since the 1960s. We hypothesized that range contraction of grouse in New York State was associated with broad-scale spatial patterns relating to forest maturation and that these patterns would be evident at the landscape scale. We evaluated data available from New York Breeding Bird Atlases conducted in the early 1980s and again in the early 2000s, which included surveys of >5,000, 25-km² sample blocks across a landscape of 125,384 km². We related detection and non-detection of grouse within Breeding Bird Atlas blocks to forest amount, landscape configuration, and presence of neighboring grouse populations via autologistic regression. Loss of early successional forest was inversely related to the continued persistence of grouse (R² = 0.61). Models showed that ruffed grouse were no longer detected in marginal areas of their distribution, blocks with low amounts of forest, and blocks with landscape configurations potentially advantageous to nest predators. We conclude that declines in both habitat quality and quantity have contributed to range contraction within New York State and that the factors affecting grouse populations have acted at broader spatial scales than are typically considered in habitat evaluation. Our work demonstrates that large landscape-scale data sets are valuable in assessing changes in distribution and abundance of wildlife populations. Landscape analyses at large geographic scales (>100,000 km²) are of particular importance to managers because they represent ways of quantifying the influence of economic incentives and land-use policy on habitats across large regions. © The Wildlife Society, 2012

Field borders established for wildlife conservation have been recognized as a possible venue for also promoting beneficial insect populations, such as parasitic wasps and pollinators, on agricultural lands. However, traditional fallow field borders lack nectar sources required to sustain beneficial insect communities, and their value to small mammals is not well-understood. In October–November 2009, we trapped small mammals in four field-border treatments (planted native, warm-season grasses and prairie flowers, planted prairie flowers only, fallow vegetation, and frequently mowed vegetation) replicated around nine organic crop fields, and developed closed-population models in Program MARK to estimate abundance in each border. We also measured vegetation cover within each border treatment from June to August 2009. We captured 491 individuals of two species, the hispid cotton rat (Sigmodon hispidus) and house mouse (Mus musculus). Cotton rat abundance was ≥2 times greater in grass and flower borders and flowers-only borders than in fallow borders, likely because of greater vegetation density and availability of preferred foods in planted borders. No cotton rats were captured in mowed borders, and house mouse abundance was ≥5 times lower in mowed borders than in other border types. Lower abundance of cotton rats and house mice in mowed borders emphasizes the importance of structurally complex non-crop vegetation for supporting small-mammal communities in agricultural landscapes. Field borders planted to promote beneficial insects may be a useful tool for maximizing the ecological services provided by non-crop vegetation. © 2012 The Wildlife Society.

Genetic markers play an important role in elucidating taxonomic uncertainties for a wide range of organisms. We present a set of specific primers to distinguish between Canis mitochondrial DNA (mtDNA) of New World (North American) and Old World (Eurasian) origin using the ATP-8 region and gel electrophoresis. We amplified mtDNA from Old World (gray wolves [Canis lupus L., 1758]) and New World canids (coyotes [C. latrans Say, 1823] and eastern wolves [C. lycaon Schreber, 1775 or C. lupus lycaon]) collected during 2003–2009 in Québec, Canada, using a multiplexed primer triplet. The results showed a standard band of 150 base pairs (bp) for New World and Old World mtDNA. In addition, Old World mtDNA displayed a second band of 100 bp. The range extent of wolves with New World mtDNA has important implications for canid conservation. The new method can assist conservation managers with rapid and cost-effective screening to monitor 1) the distribution and abundance of wolves with New World and Old World mtDNA, and 2) wolf–coyote hybridization, when used in combination with morphological information and other nuclear markers. © 2012 The Wildlife Society.

We explored a one-step method of extracting plant cuticular hydrocarbons for the analysis of diet composition, intake, and passage rate of herbivores. Alkanes (waxes produced by plants) and long-chain alcohols (LCOHs) have traditionally been extracted via a sequence of saponification and esterification (S/E) separation techniques, which are labor- and time-intensive. We improved upon the alkane method by extracting samples in hexane using Dionex's Accelerated Solvent Extractor (ASE®; Dionex Corporation, Bannockburn, IL) with simultaneous purification of long-chain hydrocarbons using Florisil® (U. S. Silica, Berkeley Springs, WV) and Davisil® (W. R. Grace & Co.-Conn., Columbia, MD) solid-phase absorbents. This improvement allows for rapid preparation of samples for analysis of both alkanes and LCOHs for gas chromatography analysis. Recovery and quantification of plant alkanes was assessed using 5 forages that were phenologically and morphologically distinct and endemic to South-central Alaska, USA, to ensure both methods were tested under conditions for which they would be used. We found that recovery of alkanes was 20% higher (P < 0.0001) for the ASE method compared with the S/E method. Correcting for recovery, we found that both methods provided equivalent estimates of alkane concentrations (r² = 0.9987). Recovery of LCOHs was significantly higher by 7.8% (P = 0.03) for the ASE method compared with the S/E method. Both methods provided similarly clean extractions, with satisfactory baseline and peak separations. We found that the single-step ASE process was effective in the extraction, purification, and quantification of both alkanes and LCOHs from plant materials, resulting in significant savings in time while using less corrosive solvents. Recoveries of both alkanes and LCOHs were higher for the ASE method. © 2012 The Wildlife Society.

In 2008, the U.S. Fish and Wildlife Service was petitioned to list the Pacific walrus (Odobenus rosmarus divergens) under the U.S. Endangered Species Act (ESA). Research into stressors that may be negatively affecting walruses is incomplete. We developed a Bayesian belief network model structured around the ESA 5-factor analysis during a workshop attended by walrus and ESA experts to 1) elicit expert opinion on important stressors and their effects, 2) develop the model, and 3) develop and analyze plausible future scenarios. The listing factors and associated stressors were organized as sub-models, capturing the cumulative effects of the factors through model output, which was the probability of negative, neutral, or positive effects. We found that in a time-constrained workshop, the graphical display of Bayesian belief networks allowed for rapid development, assessment, and revision of model structure and parameters. We modeled up to 3 scenarios (most likely-, worst-, and best-case) for each of 4 time periods (recent past, contemporary, mid-century, and late-century). Model output for the recent past (reference condition) was consistent with observations and provided a baseline for comparison of the outcomes of other periods and scenarios; stressor effects became increasingly negative with time. However, scenario analyses indicated that mitigation of relatively few stressors could reduce the cumulative effects of the listing factors. Uncertainty in model output was lowest for the past but differed by only 7% among the other time periods. We used 4 types of sensitivity analyses to identify explanatory variables that had the greatest influence on model outcomes. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.

Distance sampling during aerial surveys has been used extensively to estimate the density of many wildlife species. However, practical issues arise when using distance sampling during aerial surveys, such as obtaining accurate perpendicular distances. We assembled a computerized, electronic system to collect distance-sampling data (e.g., transect length, detection location, and perpendicular distance) during aerial surveys. We tested the accuracy of the system in a controlled trial and a mock survey. We also evaluated the electronic system during field surveys of northern bobwhite (Colinus virginianus) conducted in the Rio Grande Plains and Rolling Plains ecoregions of Texas, USA, during December 2007–2008. For comparison, we evaluated the accuracy of visual estimation of distance during a mock survey. A strong linear relationship existed between estimated and actual distances for the controlled trial (r² = 0.99) and mock survey (r² = 0.98) using the electronic system. Perpendicular-distance error (i.e., absolute difference between estimated distance and actual distance) for the electronic system was low during the controlled trial (1.4 ± 0.4 m;  ± SE) and mock survey (3.0 ± 0.5 m) but not during the visual estimation of distance (10 ± 1.5 m). Estimates of bobwhite density obtained using the electronic system exhibited reasonable precision for each ecoregion during both years (CV < 20%). Perpendicular-distance error slightly increased with target distance (0.7-m increase in error for every 10-m increase in target distance). Overall, the electronic system appears to be a promising technique to estimate density of northern bobwhite and possibly other terrestrial species for which aerial-based distance sampling is appropriate. © The Wildlife Society, 2012