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Recolonization of the Cascade Range in southern British Columbia, Canada, and Washington, USA, by wolverines ( Gulo gulo (L., 1758)) is an ongoing process whose ultimate outcome is unknown. A reliable species distribution model for the wolverine in the Cascades (i.e., their first-order habitat selection) is urgently needed to help inform management and conservation strategies. Using Argos location data obtained on 10 resident adult wolverines (six females, four males) from 2008 to 2016, we generated a multi-covariate species distribution model for the wolverine in the Cascades. Our final model included three climatic covariates and their quadratic terms: Proximity to the Transitional Zone Near Alpine Tree Line, Number of Frost-free Days per Year, and Annual Precipitation as Snow. Model validations indicated that our model was robust and could identify areas of potential wolverine distribution in the Cascades reliably. Our model provides evidence that wolverine distribution in the Cascades is constrained by climatic conditions and that snowy and cold environments define the geographic areas that are overwhelmingly associated with resident wolverines. In addition, our model provides a reliable basis for monitoring the direct effects of climate change on wolverines in the Cascade Range and for predicting the extent to which climate change may impact their populations under various scenarios.

The complex topography, climate, and geological history of Western North America have shaped contemporary patterns of biodiversity and species distributions in the region. Pacific martens (Martes caurina) are distributed along the northern Pacific Coast of North America with disjunct populations found throughout the Northwestern Forested Mountains and Marine West Coast Forest ecoregions of the West Coast. Martes in this region have been classified into subspecies; however, the subspecific designation has been extensively debated. In this study, we use genomic data to delineate conservation units of Pacific marten in the Sierra-Cascade-Coastal montane belt in the western United States. We analyzed the mitochondrial genome for 94 individuals to evaluate the spatial distribution and divergence times of major lineages. We further genotyped 401 individuals at 13 microsatellite loci to investigate major patterns of population structure. Both nuclear and mitochondrial DNA suggest substantial genetic substructure concordant with historical subspecies designations. Our results revealed that the region contains 2 distinct mitochondrial lineages: a Cascades/Sierra lineage that diverged from the Cascades/coastal lineage 2.23 (1.48–3.14 mya), consistent with orogeny of the Cascade Mountain chain. Interestingly, Pacific Martes share phylogeographic patterns similar with other sympatric taxa, suggesting that the complex geological history has shaped the biota of this region. The information is critical for conservation and management efforts, and further investigation of adaptive diversity is warranted following appropriate revision of conservation management designations.

The management of rare species is a conservation priority worldwide, but this task is made difficult by detection errors in population surveys. Both false positive (misidentification) and false negative (missed detection) errors are prevalent in surveys for rare species and can affect resulting inferences about their population status or distribution. Environmental DNA (eDNA)—DNA shed from an organism in its environment—coupled with quantitative PCR (qPCR) analyses, has become a reliable and extremely sensitive mean for identifying rare species in aquatic systems. Due to the demonstrated effectiveness of these methods, we tested their efficacy in surveys for rare species in terrestrial settings to reduce detection errors for three rare forest carnivores of conservation concern: Canada lynx (Lynx canadensis), fisher (Pekania pennanti), and wolverine (Gulo gulo). We specifically investigated our ability to reliably: 1) identify species directly from snow samples collected within tracks; 2) identify species by collecting snow in locations where an animal had been photographed; and 3) identify species from hair samples collected during the summer after being deployed throughout the winter (i.e., overwinter surveys). Our findings indicated that qPCR assays can effectively detect DNA of all three species, including from snow-track surveys, snow collected at camera stations, and overwinter samples that failed to amplify with conventional PCR techniques. All results indicate that the sources of targeted DNA collection provided adequate quantities of DNA for robust species detection. We suggest that using qPCR methods to detect DNA has the potential to revolutionize winter surveys for rare species in terrestrial settings by reducing or eliminating misidentifications and missed detections.

The Fisher (Pekania pennanti) is a mesocarnivore of conservation concern in the Pacific coastal region of North America with a diverse but poorly understood diet. From 1995 to 2001, we collected 297 scats from 11 radio-collared females and 83 scats from 8 radio-collared males, and used frequency of occurrence (percentage of scats containing a particular food item) to investigate their diets. Mammals were the most frequently occurring food item in the diets of both female and male Fishers (84.8 and 77.1 % of scats, respectively); however, the prevalence of small (≤166 g) mammalian prey was relatively low (

The Demonstration of Ecosystem Management Options (DEMO) Study is an operational-scale experiment in variable-retention harvests with six installations in western Washington and Oregon. Initiated in 1994, the experiment was designed to test key assumptions underlying standards and guidelines in the Northwest Forest Plan for regeneration harvests on matrix lands. The orthogonal portion of the six-treatment design (15 and 40 percent retention in both aggregated and dispersed patterns) is unique among large-scale variable-retention experiments, allowing for independent tests of responses to retention level and pattern and to their interaction. The DEMO Study is a multidisciplinary experiment designed to evaluate the dynamics of a diverse array of forest organisms (understory and overstory vegetation, wildlife, arthropods, and fungi), including their short-term responses to disturbance and longer term responses to changes in forest structure. However, maintaining financial support for the study over several decades has been challenging. Consequently, most studies were limited to the short term, although assessments of overstory structure and conifer regeneration extend to 18 to 19 years after treatment. This comprehensive reference document is designed to facilitate future research on the DEMO sites by providing information needed to relocate or reestablish the sampling grids, and to access existing data for comparative analyses or syntheses. It contains details on the study design, treatment histories, experimental sites, sampling infrastructure, response variables, methods and histories of sampling, and data and metadata archives.

The Cascade red fox (CRF) occurred historically throughout subalpine and alpine habitats in the Cascade Range of Washington and southernmost British Columbia, but now appears to be extremely rare. Causes for its apparent decline are unknown, as is the current distribution and connectivity of its populations. Additionally, the introduction of nonnative (fur-farm) red foxes to surrounding lowland areas during the past century raises concerns about their expansion to higher elevations and potential hybridization with the CRF. We conducted noninvasive genetic sampling and analyses of CRFs in a 5575 km2 region in the southern portion of its range, which is thought to contain a significant proportion of the current population. We obtained 154 mitochondrial DNA sequences and microsatellite genotypes for 51 individuals to determine trends in genetic diversity, assess evidence for nonnative introgression, and describe population structure. Although heterozygosity (He = 0.60, SE = 0.03) was only slightly lower than an estimate obtained from samples collected during the 1980s (He = 0.64, SE = 0.05), genetic effective size of the current population based on a one-sample estimate was very small (Ne = 16.0, 95% CI 13.3–19.4), suggesting a loss of genetic diversity and the potential for inbreeding depression in future decades. Genetic connectivity was high and we found no evidence for hybridization with nonnative lowland red foxes. Thus, although a small effective population size indicates the possibility of inbreeding depression and loss of evolutionary potential, high connectivity and genetic integrity could mitigate this to some extent, indicating that the population could respond to conservation efforts. Ultimately, successful conservation of this species depends on a better understanding of the factors that originally contributed to its decline and that currently limit its growth.

Most previous studies of resting habitat for fishers (Pekania pennanti) in the Pacific coastal region of the western United States and Canada were focused on habitat conditions within rest sites (typically ≤0.5 ha), which include the rest structure (e.g., live tree, snag, log) at its center. Studies of selection for rest structures were sparse and compared characteristics of rest structures to those occurring within rest sites; none investigated selection by sampling resource availability throughout the study area. In addition, limited data were available on the use of rest microsites (e.g., mistletoe brooms, platform branches, cavities) by fishers, and no studies have quantified their availability. To better inform forest management activities designed to improve resting habitat for fishers, we documented use of rest structures and microsites throughout the year by 12 female and 7 male fishers on the west slope of the Cascade Range in southern Oregon, USA from 1995 to 2001, systematically sampled the availability of rest structures and microsites, and used logistic regression modeling to investigate selection of rest structures. Fishers primarily used live trees (65%), snags (14%), and logs (16%) for resting; in all 3 resulting models, the characteristic that best distinguished used from available rest structures was the presence of a suitable rest microsite: mistletoe broom or cavity in live trees, cavity in snags, and hollow end in logs. Only the snag and log models included covariates associated with tree size, likely reflecting the need for enclosed rest microsites (cavities, hollow ends) to be large enough to contain an adult fisher. We then used our availability data to model the ecological characteristics associated with mistletoe brooms in live trees, cavities in snags, and hollow ends in logs. Whether a tree was a hemlock (Tsuga spp.) had the greatest effect on the presence of suitable mistletoe broom microsites, but the most important characteristics of snags with cavities and logs with hollow ends were being in moderate stages of decay and relatively large in diameter at breast height (snags) or diameter 3 m from the large end (logs). Forest structures containing suitable rest microsites for fishers were uncommon in our study and may represent a limited resource. Accordingly, we recommend that management of resting habitat for fishers be focused on retaining relatively large structures that already contain suitable rest microsites, rather than simply retaining the largest available structures. Published 2018. This article is a U.S. Government work and is in the public domain in the USA.

The Rocky Mountain Red Fox (Vulpes vulpes macroura), once common in the Blue Mountains ecoregion of northeastern Oregon, was considered rare in eastern Oregon by the 1930s and thought to be extirpated by the 1960s, when putatively new Red Fox populations began to appear. Although the new foxes were long presumed to be nonnative (originating from fur-farms or deliberate release), they were often phenotypically similar to native Red Foxes, suggesting the alternative possibility that they arose from range expansions, either by small numbers of remnant native foxes at higher elevations or by Rocky Mountain Red Foxes to the east. In this study, we used mitochondrial DNA to investigate the origins of extant Red Fox populations in northeastern Oregon. Our findings show that both native and nonnative sources contributed to the Red Fox populations currently occupying this region. In particular, Red Foxes in montane habitats of their former range in northeastern Oregon reflect predominantly native ancestry, whereas those in more lowland habitats outside the boundaries of their former range represent a mix of native and nonnative ancestry. Recognizing the existence of foxes with native ancestry in northeastern Oregon may shape management decisions regarding this species, especially in respect to control versus conservation.

Social behaviour in solitary carnivores has long been an active area of investigation but for many species remains largely founded in conjecture compared to our understanding of sociality in group-living species. The social organization of the wolverine has, until now, received little attention beyond its portrayal as a typical mustelid social system. In this chapter the authors compile observations of social interactions from multiple wolverine field studies, which are integrated into an ecological framework. An ethological model for the wolverine is proposed that reveals an intricate social organization, which is driven by variable resource availability within extremely large territories and supports social behaviour that underpins offspring development.

The availability of spatially referenced environmental data and species occurrence records in online databases enable practitioners to easily generate species distribution models (SDMs) for a broad array of taxa. Such databases often include occurrence records of unknown reliability, yet little information is available on the influence of data quality on SDMs generated for rare, elusive, and cryptic species that are prone to misidentification in the field. We investigated this question for the fisher (Pekania pennanti), a forest carnivore of conservation concern in the Pacific States that is often confused with the more common Pacific marten (Martes caurina). Fisher occurrence records supported by physical evidence (verifiable records) were available from a limited area, whereas occurrence records of unknown quality (unscreened records) were available from throughout the fisher's historical range. We reserved 20% of the verifiable records to use as a test sample for both models and generated SDMs with each dataset using Maxent. The verifiable model performed substantially better than the unscreened model based on multiple metrics including AUCtest values (0.78 and 0.62, respectively), evaluation of training and test gains, and statistical tests of how well each model predicted test localities. In addition, the verifiable model was consistent with our knowledge of the fisher's habitat relations and potential distribution, whereas the unscreened model indicated a much broader area of high-quality habitat (indices > 0.5) that included large expanses of high-elevation habitat that fishers do not occupy. Because Pacific martens remain relatively common in upper elevation habitats in the Cascade Range and Sierra Nevada, the SDM based on unscreened records likely reflects primarily a conflation of marten and fisher habitat. Consequently, accurate identifications are far more important than the spatial extent of occurrence records for generating reliable SDMs for the fisher in this region. We strongly recommend that practitioners avoid using anecdotal occurrence records to build SDMs but, if such data are used, the validity of resulting models should be tested with verifiable occurrence records.

Wolverines were greatly reduced in number and possibly extirpated from the contiguous United States (U.S.) by the early 1900s. Wolverines currently occupy much of their historical range in Washington, Idaho, Montana, and Wyoming, but are absent from Utah and only single individuals are known to occur in California and Colorado. In response, the translocation of wolverines to California and Colorado is being considered. If wolverines are to be reintroduced, managers must identify appropriate source populations based on the genetic affinities of historical and modern wolverine populations. We amplified the mitochondrial control region of 13 museum specimens dating from the late 1800s to early 1900s and 209 wolverines from modern populations in the contiguous U.S. and Canada and combined results with previously published haplotypes. Collectively, these data indicated that historical wolverine populations in the contiguous U.S. were extirpated by the early 20th century, and that modern populations in the contiguous U.S. are likely the descendants of recent immigrants from the north. The Cali1 haplotype previously identified in California museum specimens was also common in historical samples from the southern Rocky Mountains, and likely evolved in isolation in the southern ice-free refugium that encompassed most of the contiguous U.S. during the last glaciation. However, when southern populations were extirpated, these matrilines were eliminated. Several of the other haplotypes found in historical specimens from the contiguous U.S. also occur in modern North American populations, and belong to a group of haplotypes that are associated with the rapid expansion of northern wolverine populations after the last glacial retreat. Modern wolverines in the contiguous U.S. are primarily haplotype A, which is the most common and widespread haplotype in Canada and Alaska. For the translocation of wolverines to California, Colorado, and other areas in the western U.S., potential source populations in the Canadian Rocky Mountains may provide the best mix of genetic diversity and appropriate learned behavior.

Pacific martens (Martes caurina) remain common in montane regions of the Pacific states, yet their distribution and status on the Olympic Peninsula, Washington, is uncertain. Between 1968–2008, six reliable marten detections exist; a dead juvenile female (2008) indicates martens were reproducing on the Peninsula within the last decade. To assess the status of martens, we describe carnivore surveys conducted from 1991–2008 (n = 223 stations). Additionally, we present results from three survey efforts we conducted from 2013–2016 (n = 747 stations). Although a suite of carnivore species was detected, surveys from 1991–2008 failed to detect either martens or fishers. Surveys from 2013–2016 detected reintroduced fishers, and resulted in two marten detections near Mt. Olympus, 4 km apart. A marten was photographed opportunistically near Mt. Cruiser in 2015, 44 km from Mt. Olympus. Altogether, nine reliable detections of Pacific martens were obtained between 1968 and 2016, including three since 2008. Evidence suggests martens are absent from the lower elevation regions they once occupied and occur at exceedingly low densities at higher elevations. To understand the trend in marten populations on the Peninsula and develop appropriate conservation strategies, additional broad- and fine-scale surveys using detection devices that enable the genetic identification of individuals will be needed.

Thefisher (Pekania pennanti) isa species of conservationconcern throughout the Pacific coastal region in North America. A number of radiotelemetry studies of habitat selection by fishers at resting sites have been conducted in this region, but the applicability of observed patterns beyond the boundaries of each study area is unknown. Broadly applicable information on habitat selection by fishers in this region would be useful for conservationplanning andfor informingforestmanagement decisionsinareas where intensivefield studies have notbeenconducted. To providesuch information, weconducted formal meta-analysesofhabitat selection by fishers at resting sites in 8 study areas located from central British Columbia to the southern Sierra Nevada in California, including all areas that currently contain established fisher populations. Each study included in the meta-analyses measured environmental attributes at sites used byfishers for resting (i.e., the immediate vicinity of resting structures; typically � 0.5 ha) and at random or systematically located sites representing resource availability in each study area. We selected 9 environmental attributes that we expected to be associated with fisher resting sites: slope, heat load index, percent cover of vegetation � 2 m above the ground, volume of moderately decayed logs � 26 cm in mean diameter, basal area of live conifers 51-100 cm in diameter at breast height (dbh), basal area of live hardwoods 51-100 cm in dbh, basal area of moderately decayed snags 51-100 cm in dbh, mean dbh of live conifers � 10 cm in dbh, and mean dbh of live hardwoods � 10 cm in dbh. Despite substantial variation in environmental conditions among study locations, our analyses revealed statistically significant summary effect sizes for each of the 9 environmental attributes we analyzed. Fishers selected sites for resting that had steeper slopes, cooler microclimates, denser overhead cover, a greater volume of logs, and a greater prevalence of large trees and snags than were generally available. Thus, in areas within the Pacific coastal region where fishers have not been studied and data on selection of resting sites are lacking, our findings provide empirical support for management or conservation actions for fishers that promote the retention or development of these environmental attributes. 2013 The Wildlife Society.

Red foxes (Vulpes vulpes) are native to boreal and western montane portions of North America but their origins are unknown in many lowland areas of the United States. Red foxes were historically absent from much of the East Coast at the time of European settlement and did not become common until the mid-1800s. Some early naturalists described an apparent southward expansion of native foxes that coincided with anthropogenic habitat changes in the region. Alternatively, red foxes introduced from Europe during Colonial times may have become established in the east and subsequently expanded their range westward. The red fox also was absent historically from most lowland areas of the western United States. Extant populations of red foxes in those areas are considered to have arisen from intentional introductions from the east (and by extension are putatively European), escapes or releases from fur farms, or range expansions by native populations. To test these hypotheses we compared mitochondrial DNA sequences (cytochrome b and D-loop) from 110 individuals from 6 recently established populations to 327 native (primarily historical) individuals from Eurasia, Alaska, Canada, the northeastern United States, and montane areas in the western contiguous United States, and to 38 individuals from fur farms. We found no Eurasian haplotypes in North America, but found native haplotypes in recently established populations in the southeastern United States and in parts of the western United States. Red foxes from the southeastern United States were closely related to native populations in eastern Canada and the northeastern United States, suggesting that they originated from natural range expansions, not from translocation of European lineages, as was widely believed prior to this study. Similarly, recently established populations in the Great Basin and in western Oregon originated primarily from native populations in western montane regions, but also contained a few nonnative North American haplotypes. In contrast, populations in western Washington and southern California contained nonnative, highly admixed stock that clearly resulted from intracontinental translocations. Several common haplotypes in these populations originated in regions where fur-farm stocks originated. Although European red foxes translocated to the eastern United States during Colonial times may have contributed genetically to extant populations in that region, our findings suggest that most of the matrilineal ancestry of eastern red foxes originated in North America.

Boreal species sensitive to the timing and duration of snow cover are particularly vulnerable to global climate change. Recent work has shown a link between wolverine (Gulo gulo) habitat and persistent spring snow cover through 15 May, the approximate end of the wolverine's reproductive denning period. We modeled the distribution of snow cover within the Columbia, Upper Missouri, and Upper Colorado River Basins using a downscaled ensemble climate model. The ensemble model was based on the arithmetic mean of 10 global climate models (GCMs) that best fit historical climate trends and patterns within these three basins. Snow cover was estimated from resulting downscaled temperature and precipitation patterns using a hydrologic model. We bracketed our ensemble model predictions by analyzing warm (miroc 3.2) and cool (pcm1) downscaled GCMs. Because Moderate-Resolution Imaging Spectroradiometer (MODIS)-based snow cover relationships were analyzed at much finer grain than downscaled GCM output, we conducted a second analysis based on MODIS-based snow cover that persisted through 29 May, simulating the onset of spring two weeks earlier in the year. Based on the downscaled ensemble model, 67% of predicted spring snow cover will persist within the study area through 2030-2059, and 37% through 2070-2099. Estimated snow cover for the ensemble model during the period 2070- 2099 was similar to persistent MODIS snow cover through 29 May. Losses in snow cover were greatest at the southern periphery of the study area (Oregon, Utah, and New Mexico, USA) and least in British Columbia, Canada. Contiguous areas of spring snow cover become smaller and more isolated over time, but large (.1000 km 2 ) contiguous areas of wolverine habitat are predicted to persist within the study area throughout the 21st century for all projections. Areas that retain snow cover throughout the 21st century are British Columbia, north-central Washington, northwestern Montana, and the Greater Yellowstone Area. By the late 21st century, dispersal modeling indicates that habitat isolation at or above levels associated with genetic isolation of wolverine populations becomes widespread. Overall, we expect wolverine habitat to persist throughout the species range at least for the first half of the 21st century, but populations will likely become smaller and more isolated.

Most native red foxes (Vulpes vulpes) in the western contiguous United States appear to be climatically restricted to colder regions in the major mountain ranges and, in some areas, have suffered precipitous declines in abundance that may be linked to warming trends. However, another population of unknown origin has occurred in arid habitats in the Sacramento Valley of California well out- side this narrow bioclimatic niche since at least 1880. If native, this population would be ecologically distinct among indigenous North American red foxes. We used mitochondrial and microsatellite markers from historical and modern samples (modes: 1910-1930 and 2000-2008, respectively) obtained throughout the western United States to determine the origins of the Sacramento Valley red fox, and assess the historical and modern connectivity and genetic effective population sizes of Sacramento Val- ley and montane red foxes. We found clear and consistent evidence supporting the indigenous origin of the Sacra- mento Valley population, including the phylogenetic positioning of the dominant, endemic mtDNA clade and microsatellite clustering of the Sacramento Valley popu- lation with the nearest montane population. Based on both mitochondrial and microsatellite AMOVAs, connectivity among Western populations of red foxes declined sub- stantially between historical and modern time periods. Estimates based on temporal losses in gene diversity for both marker types suggest that both the Sierra Nevada (including the Southern Cascades population) and the Sacramento Valley populations have small genetic effec- tive population sizes. Significant heterozygote excesses also indicate the occurrence of recent bottlenecks in these populations. Both substitutions distinguishing the 2 ende- mic Sacramento Valley haplotypes from the dominant montane haplotype were in the coding region and nonsynonymous, consistent with adaptive differences. These findings along with previously reported body size distinctions between Sacramento Valley and montane red foxes argue for distinct subspecific status for the Sacra- mento Valley red fox, for which we propose the designa- tion V. v. patwin n. subsp. The small genetic effective population size estimates for the Sierra Nevada red fox and Sacramento Valley red fox are cause for concern, as is the possibility of genetic introgression into the latter popula- tion from an adjacent, recently established nonnative

We propose a fundamental geographic distribution for the wolverine ( Gulo gulo (L., 1758)) based on the hypothesis that the occurrence of wolverines is constrained by their obligate association with persistent spring snow cover for successful reproductive denning and by an upper limit of thermoneutrality. To investigate this hypothesis, we developed a composite of MODIS classified satellite images representing persistent snow cover from 24 April to 15 May, which encompasses the end of the wolverine’s reproductive denning period. To investigate the wolverine’s spatial relationship with average maximum August temperatures, we used interpolated temperature maps. We then compared and correlated these climatic factors with spatially referenced data on wolverine den sites and telemetry locations from North America and Fennoscandia, and our contemporary understanding of the wolverine’s circumboreal range. All 562 reproductive dens from Fennoscandia and North America occurred at sites with persistent spring snow cover. Ninety-five percent of summer and 86% of winter telemetry locations were concordant with spring snow coverage. Average maximum August temperature was a less effective predictor of wolverine presence, although wolverines preferred summer temperatures lower than those available. Reductions in spring snow cover associated with climatic warming will likely reduce the extent of wolverine habitat, with an associated loss of connectivity.

In the Pacific Northwest (PNW) region of the contiguous United States, retention of live (green) trees in harvest units is an integral part of forest management practices on federal lands, yet the ecological benefits that result from various levels or patterns of retained trees remain speculative. The Demonstration of Ecosystem Management Options (DEMO) study was established to address these informational gaps. The experimental design consists of six treatments, each 13 ha in size, replicated at six locations (blocks) in western Washington and Oregon. Treatments represent strong contrasts in retention level (15–100% of original basal area) and pattern (trees dispersed vs. aggregated in 1-ha patches) in mature Douglas-fir (Pseudotsuga menziesii) forests. A wide variety of ecological responses and public perceptions of visual quality have been examined; this paper provides a comprehensive review of the short-term (1–7 years) results of these studies. Level of retention had a strong effect on many responses. At 15% retention, regardless of pattern, microclimate, ecological responses, and public perceptions of visual quality did not differ from those measured in the ‘‘clearcut’’ areas of aggregated treatments. In contrast to level of retention, pattern of retention had limited effect on most measures of biological response. Small changes within forest aggregates were balanced by large changes in adjacent harvested areas, thus on average, responses within aggregated treatments were comparable to those in dispersed treatments. Nevertheless, retaining trees in 1-ha aggregates provided several benefits over dispersed retention. Aggregates greatly reduced damage to and mortality of residual trees (particularly at lower levels of retention) and provided short-term refugia for forest organisms sensitive to disturbance or environmental stress (e.g., bryophytes and late-seral herbs). However, aggregates were susceptible to edge effects (e.g., elevated light and temperature), which may compromise their ability to serve as sources for recolonization of adjacent harvested areas. Collectively, our findings suggest that retention levels >15% are needed to effectively retain sensitive plants and animals, ameliorate harsh microclimatic conditions, and gain public acceptance of retention harvests in these forests. A combination of relatively large (1 ha) aggregates and dispersed trees at levels considerably greater than current minimum standards in the PNW may be the most effective strategy for sustaining a broad array of forest values in managed stands. Published by Elsevier B.V.

Lynx (Lynx canadensis) occur in the northern counties of Washington state, USA; however, current distribution and status of lynx in Washington is poorly understood. During winters 2002–2004 we snow-tracked lynx for 155 km within a 211-km2 area in northern Washington, to develop a model of lynx–habitat relationships that we could use to assess their potential distribution and status in the state. We recorded movements and behaviors of lynx with a Global Positioning System and overlaid digitized lynx trails on various habitat layers using a Geographic Information System. Based on univariate analyses, lynx preferred Engelmann spruce (Picea engelmannii) and subalpine fir (Abies lasiocarpa) forests, with moderate canopy and understory cover, and elevations ranging from 1,525 m to 1,829 m but avoided Douglas-fir (Pseudotsuga menziesii) and ponderosa pine (Pinus ponderosa) forests, openings, recent burns, open canopy and understory cover, and steep slopes. A map of suitable lynx habitat based on a logis...

Effectively managing habitat for threatened populations of Canada lynx (Lynx canadensis) requires knowledge of habitat conditions that provide for the ecological needs of lynx. We snow-tracked lynx to identify habitat conditions associated with hunting behavior and predation during winters of 2002–2003 and 2003–2004 in the northern Cascade Range in Washington state, USA. We recorded number and success of predation attempts, prey species killed, and trail sinuosity on 149 km of lynx trails. Lynx killed snowshoe hares (Lepus americanus), red squirrels (Tamiasciurus hudsonicus), and cricetids more than expected in Englemann spruce (Picea engelmannii) and subalpine fir (Abies lasiocarpa) forests, where snowshoe hare densities were highest. Lynx killed prey less than expected in Douglas-fir (Pseudotsuga menziesii) and ponderosa pine (Pinus ponderosa) forests and forest openings. We used the sinuosity of lynx trails as an index of quality of habitat hunted. Lynx trails that included predation attempts were more sinuous than trail segments without predation attempts. Lynx trails had greater sinuosity in forest stands with high hare densities dominated by Engelmann spruce and subalpine fir than in stands with low hare densities dominated by Douglas-fir and ponderosa pine or in forest openings. We encourage forest managers to maintain or create sufficient understory cover to support high densities of snowshoe hares as foraging habitat for lynx.

Anecdotal occurrence data (unverifiable observations of organisms or their sign) and inconclusive physical data are often used to assess the current and historical ranges of rare or elusive species. However, the use of such data for species conservation can lead to large errors of omission and commission, which can influence the allocation of limited funds and the efficacy of subsequent conservation efforts. We present three examples of biological misunderstandings, all of them with significant conservation implications, that resulted from the acceptance of anecdotal observations as empirical evidence. To avoid such errors, we recommend that a priori standards constrain the acceptance of occurrence data, with more stringent standards applied to the data for rare species. Because data standards are likely to be taxon specific, professional societies should develop specific evidentiary standards to use when assessing occurrence data for their taxa of interest.

In the Pacific Northwest, providing adequate habitat for pileated woodpeckers (Dryocopus pileatus) has been a key component of federal forest management strategies for over 20 years. Although their nesting and roosting ecology has been well studied, information on their foraging ecology is limited. From 1990 to 1995, we studied food habits of pileated woodpeckers in coastal forests (with scat analysis); estimated the relative abundance of their primary prey, carpenter ants (Camponotus spp.), associated with logs and cut stumps; and investigated selection of forest structures and site characteristics used by pileated woodpeckers for foraging. Pileated woodpeckers primarily consumed carpenter ants (54% of diet), but round-headed beetle larvae (Coleoptera, Cerambycidae) and dampwood termites (Isoptera, Termopsidae) were important food items during the breeding season (Mar–Jun). Selection of foraging structures was related to wood characteristics and microsite conditions that influence the presence and abundance of arthropod prey. Pileated woodpeckers foraged almost exclusively (95%) on standing structures, selecting tall, large-diameter snags in early to moderate stages of decay. Contrary to previous studies, pileated woodpeckers rarely (2%) foraged on logs. Carpenter ants were scarce at logs in closed-canopy habitats, which suggested that in coastal forests logs are too cool and wet to support abundant populations of carpenter ants. Selection of foraging sites by pileated woodpeckers was influenced by the abundance of potential foraging structures; 0.4-ha plots with recent foraging activity had greater densities of large snags (>51 cm dbh and ≥7.5 m tall) than plots without recent foraging. The efficacy of management strategies designed to provide habitat for pileated woodpeckers would be enhanced if they included specific provisions for foraging habitat and accounted for regional differences in the types of structures that provide suitable conditions for wood-dwelling arthropods.

Snow tracking is often used to inventory carnivore communities, but species identification using this method can produce ambiguous and misleading results. DNA can be extracted from hair and scat samples collected from tracks made in snow. Using DNA analysis could allow positive track identification across a broad range of snow conditions, thus increasing survey accuracy and efficiency. We investigated the efficacy of DNA identification using hairs and scats collected during the winter along putative Canada lynx (Lynx canadensis) snow tracks and compared our findings to those obtained using hair-snaring techniques during the summer. We were able to positively identify 81% and 98% of the hair and scat samples, respectively, that were collected in or near snow tracks. Samples containing amplifiable lynx DNA were collected at rates of 1.2–1.3 per km of lynx tracks followed. These amplification rates and encounter frequencies validate the collection and use of DNA samples from snow tracks as a feasible technique for identifying Canada lynx and possibly other rare carnivores. We recommend that biologists include the collection of hairs and scats for DNA analysis as part of snow-tracking surveys whenever species identification is a high priority.

Evolutionary processes can be strongly affected by landscape features. In vagile carnivores that disperse widely, however, genetic structure has been found to be minimal. Using microsatellite DNA primers developed for other mustelids, we found that populations of a vagile forest carnivore, the fisher (Martes pennanti), exhibit high genetic structure (FST ¼ 0.45, SE ¼ 0.07) and limited gene flow (Nm , 1) within a .1,600-km narrow strip of forested habitat; that genetic diversity decreases from core to periphery; and that populations do not show an equilibrium pattern of isolation-by-distance. Genetic structure was greater at the periphery than at the core of the distribution and our data fit a 1-dimensional model of stepping-stone range expansion. Multiple lines of paleontological and genetic evidence suggest that the fisher recently (,5,000 years ago) expanded into the mountain forests of the Pacific coast. The reduced dimensionality of the distribution of the fisher in western coastal forests appears to have contributed to the high levels of structure and decreasing diversity from north to south. These effects were likely exacerbated by human-caused changes to the environment. The low genetic diversity and high genetic structure of populations in the southern Sierra Nevada suggest that populations in this part of the geographic range are vulnerable to extinction.

Translocation of animals to re-establish extirpated populations or to maintain declining ones has often been carried out without genetic information on source or target populations, or adequate consideration of the potential effects of mixing genetic stocks. We consider the conservation status of the fisher (Martes pennanti) and evaluate the potential genetic consequences of past and future translocations on this medium-sized carnivore by examining population variation in mitochondrial control-region sequences. We sampled populations throughout the fisher's range in North America including five populations unaffected by translocations and two western populations that had received long-distance translocations. Twelve haplotypes showed little sequence divergence. Haplotype frequencies differed significantly among subspecies and between populations within subspecies. Analysis of molecular variance (amova) and neighbour-joining analyses of haplotype relationships revealed population subdivision similar to current subspecies designations, but which may reflect an isolation-by-distance pattern. Populations in Oregon and in Montana and Idaho received several translocations and each showed greater similarity to the populations where translocations originated than to adjacent populations. Additional sequences obtained from museum specimens collected prior to any translocations suggest historical gene flow among populations in British Columbia, Washington, Oregon, and California. Anthropogenic impacts in that region have greatly reduced and isolated extant populations in Oregon and California. Future translocations may be necessary to recover populations in Washington and portions of Oregon and California; our results indicate that British Columbia would be the most appropriate source population.

Several recent studies base assessment of conservation priorities primarily on the current protection status of vertebrate species and vegetation communities. Our objective was to compare prioritization using current protection status alone with prioritization using more traditional methods. We mapped land cover of Washington State at a 100 ha minimum mapping unit using 1991 Landsat satellite thematic mapper imagery, and modeled the distributions of all breeding terrestrial vertebrates in the State using the land cover map. We determined the level of protection for each vertebrate species based on its current modeled distribution and for vegetation communities based on their current mapped distribution. We also compiled subjective lists of vertebrate species most at risk from human activities and vertebrate species most well-adapted to human activities, and we used information about potential vegetation and historic conditions to determine past anthropogenic conversion of vegetation communities. We concluded that, while knowledge of current protection status is critical for assessing conservation priorities, use of such information without ecological context (potential vegetation and historic conditions for vegetation and habitat requirements, population trends, and historic distribution for vertebrates) can give results that would direct scarce conservation resources to species and communities unlikely to need protection in the foreseeable future.