In two recent studies, North American river otters (Lontra canadensis) inhabiting the urbanized/industrialized harbors of southern Vancouver Island, British Columbia, Canada were found to be exposed to elevated levels of environmental contaminants, primarily industry-produced polychlorinated biphenyls (PCBs). Contaminant exposure in those studies was assessed non-invasively, by measuring chemical residue concentrations in river otter feces collected from established marking sites (latrines). As river otter exposure to contaminants is primarily through their diet, our aim was to characterize river otter prey selection from feces collected at latrine sites inside the contaminated harbors and along the relatively uncontaminated coastline outside the harbor systems. Fish occurred in 95.5% of all feces analyzed, with species of gunnels (Pholidae), sculpins (Cottidae), pricklebacks (Stichaeidae), toadfish (Batrachoididae), clingfish (Gobiesocidae), flatfish (Pleuronectiformes), and snailfish (Liparidae) being the most common prey consumed. Crustaceans were the only non-fish prey identified. Feces collected outside the harbors had a higher prevalence of pricklebacks, clingfish, and greenlings, whereas feces collected inside the harbor systems had a higher prevalence of toadfish and crustaceans. Because of the diversity of the river otter's diet, prey species from each of the main families described here should be analyzed for environmental contaminants to fully characterize concentrations of persistent compounds in the food-web. Prey sampling should be location-specific (i.e., inside and outside the urban/industrial harbors) to elucidate possible location effects on contaminant exposure.

We characterized winter concealment behavior (WCB) for juvenile spring Chinook salmon (Oncorhynchus tshawytscha) from October through January in three study streams of the Grande Ronde River Basin, Oregon. The Nocturnal Index (NI), the frequency of fish using WCB, increased significantly as mean daily water temperature decreased. WCB was negatively associated with mean daily water temperature in all three streams, and positively associated with fish size in Catherine Creek and the Lostine River. WCB was not significantly associated with fish density in any of the three streams. Both the NI and detections of concealed fish indicated that fish were concealing amid interstitial spaces during the day and emerging at night as early as October-November, yet no population fully exhibited WCB during any month sampled. Although low water temperature influenced WCB in the Grande Ronde River Basin, other ecological factors affected the behavior because not all fish used WCB even when mean daily water temperatures were < 1°C.

The effects of large ungulate herbivory on plant community structure and composition can vary considerably in regions susceptible to frequent wildfires. The Cerro Grande Fire (CGF) of May 2000 burned 17,400 ha of elk transitory-use range in the Jemez Mountains, north-central New Mexico. Our objective was to determine if habitat use changed temporally following the fire and if graminoid cover offset use of regenerating woody species. We assessed female elk habitat use at the landscape, home range, and burned area scales using distance analyses techniques, diet analyses, and browsing data. Across the landscape, elk selected home ranges with a grassland component. Selection of home ranges across the landscape was not influenced by the burned area within 4 years post-fire. Within home ranges, preference for burned area was similar to other habitats suggesting the burned area played a more important role at the home range scale compared to the landscape scale, particularly during drought. The presence of graminoids in elk pellets collected from the burned area increased while shrubs decreased over time. The decrease in shrubs may have been due to an increase in graminoid production after the fire. Applying burn treatments to transitory ranges in the Jemez Mountains at a rate that will maintain growth of early to mid-seral stage vegetation may help off-set use of sensitive woody plant communities via the production of graminoids. Re-seeding grasses immediately following fire may help to reduce herbivore use of woody plants such as aspen during the earlier stages of re-growth.

This was a study of vegetation and soil properties in tree-fall gaps in a coniferous forest of the Pacific Northwest. It had three objectives: (1) to determine if there are correlations between above-ground vegetation and below-ground soil properties within large 50 m diameter gaps, (2) to determine how large gaps influence forest soils compared with non-gap soils, and (3) to measure the effects of differently sized gaps on gap soils. To address these objectives, circular canopy gaps were created in old-growth Douglas-fir forests of the H. J. Andrews Experimental Forest in the western Oregon Cascade Mountains. To address the first objective, within-gap soil spatial patterns were compared with above ground distributions of both vegetation and large woody debris in two large gaps. Spatial and Pearson correlation analyses showed no consistent correlations between soil characteristics and above ground vegetation and coarse woody debris. With reference to the second objective, statistically significant differences between gap and non-gap soil characteristics were observed. Soil moisture, temperature and denitrification potentials were all elevated in forest 50 m diameter gaps and litter depth, labile C, soil respiration, β-gluosidase activity, and ectomytcorrhizal mat concentrations were all reduced. Comparisons between north and south gap soils, showed significant differences in soil characteristics in one but not the other 50 m gap. The third objective was addressed by documenting gap size effects on differences between gap and non gap soil characteristics in two gaps each of 10, 20, 30, and 50 m diameter. Differences between gap and nongap soil moisture, litter depth and ectomycorrhizal mat coverages were essentially the same regardless of gap size. Soil respiration rates and soil organic matter concentrations were similar in 10 m gaps but both lower in gaps 20 m and larger.

Population genetics can facilitate efforts to curb amphibian decline by enabling accurate delineation of population boundaries and by characterizing extant genetic diversity. We used data from five microsatellite markers, which are highly variable and thus can resolve fine-scale genetic patterns, to conduct a preliminary investigation of nuclear genetic diversity among broadly distributed populations of coastal giant salamanders (Dicamptodon tenebrosus), a Pacific Northwest endemic threatened by deforestation and habitat fragmentation in the northern part of its range. The main aim was to compare a limited nuclear genetic data set with already available mitochondrial DNA (mtDNA) data and to summarize what available genetic data suggests in terms of conservation management for this species. Multiple measures presented here support that northern and southern groups of coastal giant salamanders are highly divergent genetically. Results presented here were consistent with those from an mtDNA study, thus supporting earlier evidence of very high levels of genetic divergence between northern and southern groupings separated by the Columbia River Valley. Available genetic evidence suggests that conservation management for this species should at minimum recognize these two groups as distinct units. Despite sparse sampling of the southern group of coastal giant salamanders in this study, results showed evidence of remarkably high genetic diversity there such that further study is recommended to fully characterize fine-scale population level structuring, which would ensure that all distinct genetic units within the species have been elucidated.

There is growing concern in the Pacific Northwest over predation by migratory male California sea lions (Zalophus californianus) on threatened and endangered salmonid (Onchorynchus spp.) stocks. We compared movements of 14 male California sea lions known to have previously consumed salmonids at Bonneville Dam on the Columbia River or Willamette Falls on the Willamette River (“river”-types), with 12 animals of unknown foraging history (“unknown”-types). We captured sea lions in the Columbia River and instrumented them with satellite-linked transmitters during 2003–2004, 2004–2005, and 2006–2007. Transmitters operated for an average of 87.9 d (range 23-200 d) resulting in 14,539 location fixes. All 14 river-type animals returned to either Bonneville Dam or Willamette Falls whereas none of the 12 unknown-types exhibited this behavior. Minimum upstream and downstream transit times between the mouth of the Columbia River and Bonneville Dam (210 rkm) were 1.9 d and 1 d. Duration at the dam ranged from 2 d to 43 d. The median start dates of the southbound migration from the Columbia River to the breeding grounds for river-type and unknown-type sea lions were 20 May and 15 June, respectively. The maximum travel speed during migration was approximately 130 km d^-1 (5.4 km h^-1). Our results clearly show that not all California sea lions in the Columbia River prey on salmonids at Bonneville Dam or Willamette Falls. However, factors influencing recruitment into the upriver salmonid-foraging subpopulation are unknown.

Site factors predispose yellow-cedar (Chamaecyparis nootkatensis D. Don (Spach)) to a widespread climate-induced mortality in Southeast Alaska. We investigated the influence of canopy cover and snow on microclimate at two small watersheds across a range of declining yellow-cedar stands on Baranof and Chichagof Islands in Southeast Alaska. Two measures of canopy cover, derived from hemispherical photography and LiDAR, were correlated (r = 0.74 and 0.80) at the two sites; both had significant relationships (all R2 ≥ 0.61) with basal area of live trees on plots. Reduced canopy cover increases soil warming in spring and leads to rapid changes in air temperature. There is also a positive feedback where the loss of tree overstory due to yellow-cedar mortality contributes to open, exposed site conditions. Variable patterns of snow depth in late winter and spring at one of the sites, documented with daily remote photography, were associated with elevation and cover. Dead trees predominate where lethal shallow soil temperatures occurred but not where snow buffers these temperatures because of existing snow pack. Canopy cover estimates, landscape analysis, and snow modeling could provide the components for a regional risk model to identify areas in Southeast Alaska that are suitable and unsuitable for future conservation and management of yellow-cedar.

We used fire scars and tree ages to reconstruct a 440-year fire history in a portion of the Elwha River watershed, Olympic National Park, Washington. At least nine fire events occurred in the 1873 ha study area during the period 1568 to 2007. Reconstructed fires occurred in 1568, 1661, 1676, 1729, 1868, 1890, 1898, 1927, and 1977. A 140-year natural fire rotation and a 127-year mean fire return interval were calculated for the study area. Fires were more frequent on south aspects, at low elevations, and in Douglasfir forest types. Fire suppression has likely prevented fires larger than 20 ha over the past century although large fires were also absent during a 140-year period in the 18th and 19th centuries. Continued suppression may limit forest structural heterogeneity and the establishment of early seral species in this area.

Historical records of moose (Alces alces) in Washington are limited to the northeastern corner of the state. There are no paleozoological records of moose in Washington. Since the beginning of the third millennium, moose have been occasionally reported in southeastern Washington. A sub-adult bull moose was photographed in southeastern Washington in July 2009, about 80 km west of the nearest historically documented occurrence of moose. The observed individual and other recent sightings in southeastern Washington are likely the result of an increasing population of Idaho moose and their expansion into western areas of that state and eastern Washington.

We developed a stereophotographic technique to estimate browse use by moose. We collected 30 whole plant specimens representing 4 different browse species and placed them in an outdoor compound on the campus of The University of Northern BC. We physically counted all branches on each plant and categorized them as recently browsed, browsed prior to the preceding winter, or unbrowsed. Then, we stereophotographed the plants against a white backdrop in ambient outdoor light. We viewed stereopair prints under a stereoviewer and classified them using the same method as was used in manual counting. We found that this stereophotographic technique tended to underestimate total browse removal, but allowed us to determine browse availability (the number of unbrowsed shoots) and percentage of plant shoots removed by browsing for all species examined. Of the 4 species we examined, we were able to most accurately determine the number of total browsed shoots through stereoscopy on Cornus stolonifera, Acer douglasii and Salix scouleriana while the percentage of newly browsed shoots was best determined on Betula papyrifera, A. douglasii and C. stolonifera. Our findings suggested that estimating browse supply with stereophotography is possible, whereas estimating browse use is more appropriate for some species, but not for others. With adjustments, the method may be useful in reducing field time and costs involved with spring browse surveys.

We report here the first records of the non-native northern crayfish (Orconectes virilis) in the Columbia River basin within Washington State. Confirmed occurrences include the reservoirs Lake Rufus Woods and Lake Roosevelt on the Columbia River, North Twin Lake in the upper Columbia River basin, Lake Patterson in the Methow River basin, Wapato Lake in the Lake Chelan basin, and Moses Lake in central Washington. Uncertainty remains as to the source, extent of current distribution, and potential impacts of these O. virilis populations. Release of live bait by anglers is a common pathway for crayfish introductions, although stocking for harvest or aquaculture and releases of pets or laboratory animals is equally likely for the introduction of O. virilis to the region. Evaluating potential impacts of O. virilis on native crayfish, fish, and other species in the Columbia River basin will require additional study. These newly discovered O. virilis populations are likely to naturally disperse further through the Columbia River, its tributaries, and the irrigation infrastructure of central Washington's Columbia Basin Project.

The Point Arena mountain beaver (Aploclontia rufa nigra) is a federally listed endangered species, but has been the subject of few studies. Mountain beavers use burrows that include a single subterranean den. Foremost among the information needs for this subspecies is a description of the above-ground habitat features associated with dens. Using telemetry we located dens of 23 individuals in Manchester State Park, Mendocino County, California. We measured vegetation and topographic variables directly above the dens and at two availabel sites within the same burrow system. Alternative resource selection functions, based on multivariate expressions of important ecological characteristics, were developed to model features associated with dens. The best model contained three variables: MEANDENS (mean vegetation density), PAMBTOP4 (cover of the four plant species most frequently used), and COSASPECT (cosine aspect). Interestingly, PAMBT0P4 was negatively associated with dens, indicating that dens were not chosen for their proximity to important plant species. Topography plays an important role in that western and northern aspects were favored and SLOPE was included in the second-highest ranked model. Cross validation indicated moderate stability for the top model suggesting that potentially important predictors that were excluded from the analysis (e.g., soil characteristics, social context) may be influential. Nonetheless, we demonstrated that dense vegetation and aspect/slope considerations are more important predictors of Point Arena mountain beaver den selection than proximity to cover of important plant species. Our results apply to Point Arena mountain beaver populations in coastal shrub communities; den selection may be different farther inland, in forests.

We assessed species composition and relative biomass densities of large medusae (bell diameters larger than 4 cm) at four locations in Puget Sound, Washington, over two sampling periods (June and September). We specifically sampled sites in southern Hood Canal (near Hoodsport), northern Hood Canal (Hazel Point), southern Admiralty Inlet (Useless Bay) and Possession Sound using a bottom trawl as part of a larger survey of demersal fish and invertebrate community structure. In total, four species were observed during June sampling: three schyphomedusae (Phacellophora camtschatica, Cyanea capillata, Aurelia labiata) and one hydromedusa (Aequorea victoria). The highest jellyfish densities in June were observed off Hoodsport where Aurelia labiata and Cyanea capillata dominated the assemblage. In the remaining locations, Cyanea capillata dominated catches. In September, relative biomass densities were lower throughout the area surveyed and species composition simplified with usually one species of jellyfish clearly dominating each location. Our results indicate that jellyfish biomass changed markedly within and among locations, which has implications for modeling energy flows in Puget Sound and developing monitoring schemes that are able to capture interannual variability in jellyfish biomass. Given the abundance of jellyfish in our survey and their potential as sentinels of change in the marine environment we recommend that jellyfish populations be routinely monitored in Puget Sound.

The Whitetail Watershed Restoration Project used prescribed fire in 2005 and 2006 to address quaking aspen (Populus tremuloides Michx.) decline, conifer encroachment and altered hydrologic function in a forested watershed in southwest Montana. As part of this effort, we evaluated aspen response to fire in two sub-drainages of the Whitetail Basin three years after treatment. Unburned stands were surveyed to determine whether aspen regeneration was occurring following long term disruption of historical fire return intervals. This information was compared to stem response in nearby burned stands. Regeneration was noted in only one of 40 unburned stands, suggesting aspen stands were declining in this area. Three years after prescribed fire sucker density was significantly higher in the burned stands. This increased the likelihood that stands could regenerate. Based on earlier studies describing suppression of stand regeneration by cattle (Bos taurus) and elk (Cervus elaphus nelsoni) browsing impacts on aspen sucker height and density were measured in a sub-sample of burned stands. Within the first three years post-fire big game and the combination of big game and cattle did not affect sucker density in the burned stands. Although sucker height was significantly less in plots used by ungulates it may not be high enough to prevent regeneration. This assertion was supported by sufficient annual growth rates and the recruitment of individual regeneration stems into burned stands. Results from this study indicate that aspen stands can be successfully regenerated in areas where elk numbers are less than 1 animal/km² and cattle grazing is closely managed. Monitoring will continue to learn if stand regeneration does occur.

We measured winter thermal characteristics longitudinally in four third-order streams, two each in the Idaho Batholith and Blue Mountain ecoregions. From November to April we measured temperature along 3.7 km to 11.9 km of stream at six to eight sites. Streams were snow covered for most of the winter. There was a seasonal pattern of stream-wide cooling in November and warming in April at all streams. In the mid-winter months (December, January, and February), the sites in the Blue Mountain streams had mean monthly maxima ranging from 0.2 to 3.0 °C and minima -0.1 to 1.5 °C stream-wide, whereas both Idaho Batholith streams were near 0.0 °C throughout their length and had monthly ranges of 0.2 °C or less. Winter temperature differences between streams of the two ecoregions create substantial differences in cumulative degree-days which could be a factor in the structure of instream biotic communities.

Voles are well-known crop pests, especially when peak populations are present, but their role in soil fertility and impacts on agricultural sustainability are not well understood. Five months after the abrupt disappearance of a peak in a gray-tailed vole (Microtus canicaudus) population, we examined burrow structure, determined concentrations of trace elements, carbon and nitrogen in the soil immediately surrounding vole burrows, and compared soil chemical properties to a depth of 90 cm between areas with prior vole activity and areas of no activity. Vole tunneling activity was confined to the top 10 cm of the soil profile and was coincident with the majority of root biomass. Soil NH₄ , NO₃^-, extractable organic carbon, and soil organic matter were greater below vole tunnels than above; however, due to small sample sizes, differences were not significant. There were no differences in trace elements with respect to position around vole tunnels. Vole activity was associated with increased soil nitrate concentrations and decreased soil pH to a depth of 90 cm, indicating that nitrification might be enhanced by vole activity, and that this effect continues after vole populations crash. Greater inorganic nitrogen could have long-term effects on ecosystem productivity. The effects voles have on soil processes that influence carbon and nutrient cycle requires further investigation.

Identification of biodiversity hotspots (hereafter, hotspots) has become a common strategy to delineate important areas for wildlife conservation. However, the use of hotspots has not often incorporated important habitat types, ecosystem services, anthropogenic activity, or consistency in identifying important conservation areas. The purpose of this study was to identify hotspots to improve avian conservation efforts for Species of Greatest Conservation Need (SGCN) in the state of Idaho, United States. We evaluated multiple approaches to define hotspots and used a unique approach based on weighting species by their distribution size and conservation status to identify hotspot areas. All hotspot approaches identified bodies of water (Bear Lake, Grays Lake, and American Falls Reservoir) as important hotspots for Idaho avian SGCN, but we found that the weighted approach produced more congruent hotspot areas when compared to other hotspot approaches. To incorporate anthropogenic activity into hotspot analysis, we grouped species based on their sensitivity to specific human threats (i.e., urban development, agriculture, fire suppression, grazing, roads, and logging) and identified ecological sections within Idaho that may require specific conservation actions to address these human threats using the weighted approach. The Snake River Basalts and Overthrust Mountains ecological sections were important areas for potential implementation of conservation actions to conserve biodiversity. Our approach to identifying hotspots may be useful as part of a larger conservation strategy to aid land managers or local governments in applying conservation actions on the ground.

The freshwater polychaete Manayunkia speciosa serves as the obligate intermediate host for the myxosporean parasites Ceratomyxa shasta and Parvicapsula minibicornis, which adversely affect the survival and freshwater production of juvenile salmon in the Klamath River and elsewhere in the Pacific Northwest USA. Scant information on the life history of the polychaete and inability to maintain individuals in culture has hindered development of management strategies to control disease outbreaks in Klamath River salmon. Through trial-and error- manipulations of food and water sources, culture environments and water velocities, we established conditions that allowed us to maintain M. speciosa in culture over a 10-mo period. In lab culture, eggs and young were brooded within the maternal tube for a 6–8 wk period during which 5 developmental stages were distinguished. Peak egg production occurred in late spring-early summer, with each female brooding up to 35 offspring. Juveniles left the maternal tube at a length of approximately 1 mm, and became reproductively mature in late December to early January at a length of approximately 2 mm. Duration of survival in lab culture, coupled with the absence of adult polychaetes in preserved river samples that were collected in mid-summer, suggests that M. speciosa has an approximately annual generation time.

We examined old bark lesions on Lutz spruce in young stands on the Kenai Peninsula, Alaska, to determine their cause. Distribution of these lesions along lower stems was similar to the distribution of spruce beetle attacks during epidemics. These lesions apparently resulted from unsuccessful attacks by spruce beetles during the late 1980s and early 1990s and appear to be symptomatic of conifer tree resistance reactions to cambial zone injury by Dendroctonus beetles.

Laboratory experiments were conducted to measure the prolonged-sustained and burst swimming speeds of wild larval (ammocoete) Pacific lamprey (Lampetra tridentate). Prolonged-sustained speeds were measured using an annular variable speed swimming chamber and burst speeds were determined using a swimming raceway and digital video analysis. During prolonged-sustained swimming experiments, the mean length of time lamprey (72 – 143 mm TL) were able to swim in the chamber ranged from 43.0 min when exposed to a velocity of 10 cm/s, to 0.4 min when exposed to 50 cm/s. The burst swimming speeds of lamprey tended to increase as length increased from 107 to 150 mm TL, and ranged from 33.3 to 75.0 cm/s. Our estimates of the overall swimming performance of this life-stage are the first reported for this species, and can provide important information when developing approach velocities and infrastructure to improve lamprey passage while minimizing entrainment loss.