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Montesano, WA, United States

Cook R.C.,National Council for Air and Stream Improvement Inc. | Cook J.G.,National Council for Air and Stream Improvement Inc. | Stephenson T.R.,07 W Line Street | Myers W.L.,315 Discovery Place | And 8 more authors.
Journal of Wildlife Management

Because they do not require sacrificing animals, body condition scores (BCS), thickness of rump fat (MAXFAT), and other similar predictors of body fat have advanced estimating nutritional condition of ungulates and their use has proliferated in North America in the last decade. However, initial testing of these predictors was too limited to assess their reliability among diverse habitats, ecotypes, subspecies, and populations across the continent. With data collected from mule deer (Odocoileus hemionus), elk (Cervus elaphus), and moose (Alces alces) during initial model development and data collected subsequently from free-ranging mule deer and elk herds across much of the western United States, we evaluated reliability across a broader range of conditions than were initially available. First, to more rigorously test reliability of the MAXFAT index, we evaluated its robustness across the 3 species, using an allometric scaling function to adjust for differences in animal size. We then evaluated MAXFAT, rump body condition score (rBCS), rLIVINDEX (an arithmetic combination of MAXFAT and rBCS), and our new allometrically scaled rump-fat thickness index using data from 815 free-ranging female Roosevelt and Rocky Mountain elk (C. e. roosevelti and C. e. nelsoni) from 19 populations encompassing 4 geographic regions and 250 free-ranging female mule deer from 7 populations and 2 regions. We tested for effects of subspecies, geographic region, and captive versus free-ranging existence. Rump-fat thickness, when scaled allometrically with body mass, was related to ingesta-free body fat over a 38522-kg range of body mass (r2 0.87; P < 0.001), indicating the technique is remarkably robust among at least the 3 cervid species of our analysis. However, we found an underscoring bias with the rBCS for elk that had >12 body fat. This bias translated into a difference between subspecies, because Rocky Mountain elk tended to be fatter than Roosevelt elk in our sample. Effects of observer error with the rBCS also existed for mule deer with moderate to high levels of body fat, and deer body size significantly affected accuracy of the MAXFAT predictor. Our analyses confirm robustness of the rump-fat index for these 3 species but highlight the potential for bias due to differences in body size and to observer error with BCS scoring. We present alternative LIVINDEX equations where potential bias from rBCS and bias due to body size are eliminated or reduced. These modifications improve the accuracy of estimating body fat for projects intended to monitor nutritional status of herds or to evaluate nutrition's influence on population demographics. © The Wildlife Society. Source

Cook R.C.,National Council for Air and Stream Improvement Inc. | Cook J.G.,National Council for Air and Stream Improvement Inc. | Vales D.J.,Muckleshoot Indian Tribe | Johnson B.K.,401 Gekeler Lane | And 15 more authors.
Wildlife Monographs

Demographic data show many populations of Rocky Mountain (Cervus elaphus nelsoni) and Roosevelt (Cervus elaphus roosevelti) elk have been declining over the last few decades. Recent work suggests that forage quality and associated animal nutritional condition, particularly in late summer and early autumn, influence reproduction and survival in elk. Therefore, we estimated seasonal nutritional condition of 861 female elk in 2,114 capture events from 21 herds in Washington, Oregon, Wyoming, Colorado, and South Dakota from 1998 to 2007. We estimated ingesta-free body fat and body mass, and determined age, pregnancy status, and lactation status. We obtained estimates for most herds in both late winter-early spring (late Feb-early Apr) and in autumn (Nov-early Dec) to identify changes in nutritional condition of individuals across seasons. Body fat levels of lactating females in autumn were consistently lower than their non-lactating counterparts, and herd averages of lactating elk ranged from 5.5% to 12.4%. These levels were 30-75% of those documented for captive lactating elk fed high-quality diets during summer and autumn. Body fat levels were generally lowest in the coastal and inland northwest regions and highest along the west-slope of the northern Cascades. Adult females in most herds lost an average of 30.7 kg (range: 5-62 kg), or about 13% (range: 2.6-25%) of their autumn mass during winter, indicating nutritional deficiencies. However, we found no significant relationships between spring body fat or change in body fat over winter with winter weather, region, or herd, despite markedly different winter weather among herds and regions. Instead, body fat levels in spring were primarily a function of fat levels the previous autumn. Thinner females in autumn lost less body fat and body mass over winter than did fatter females, a compensatory response, but still ended the season with less body fat than the fatter elk. Body fat levels of lactating females in autumn varied among herds but were unrelated to their body fat levels the previous spring. Within herds, thinner females exhibited a compensatory response during summer and accrued more fat than their fatter counterparts over summer, resulting in similar body fat levels among lactating elk in autumn despite considerable differences in their fat levels the previous spring. Level of body fat achieved by lactating females in autumn varied 2-fold among herds, undoubtedly because of differences in summer nutrition. Thus, summer nutrition set limits to rates of body fat accrual of lactating females that in turn limited body condition across the annual cycle. Pregnancy rates of 2- to 14-year-old females ranged from 68% to 100% in coastal populations of Washington, 69% to 98% in Cascade populations of Washington and Oregon, 84% to 94% in inland northwestern populations of Washington and Oregon, and 78% to 93% in Rocky Mountain populations. We found evidence of late breeding, even in herds with comparatively high pregnancy rates. Mean body mass of calves (n = 242) in 3 populations was 75 kg, 81 kg, and 97 kg, representing 55-70% of potential mass for 6- to 8-month-old calves on high-quality diets. Mean mass of 11 yearling females caught in autumn was 162 kg, approximately 70% of potential for autumn, and pregnancy rate was 27%. Mean mass of 28 yearlings caught in spring was 163 kg and pregnancy rate was 34%. Our data suggest widespread occurrence of inadequate summer nutrition. Summer ranges of just 3 herds supported relatively high levels of autumn body fat (11-13% body fat) and pregnancy rates (>90%) even among females that successfully raised a calf year after year. Most other summer ranges supported relatively low autumn levels of body fat (5-9% body fat), and reproductive pauses were common (<80% pregnancy rates). Overall, our data failed to support 2 common assumptions: 1) summer and early autumn foraging conditions are typically satisfactory to prevent nutritional limitations to adult fat accretion, pregnancy rates, and calf and yearling growth; and 2) winter nutrition and winter weather are the principal limiting effects on elk productivity. Instead, a strong interaction existed among level of summer nutrition, lactation status, and probability of breeding that was little affected by winter conditions - adequacy of summer nutrition dictated reproductive performance of female elk and growth as well as growth and development of their offspring in the Northwest and Rocky Mountains. Our work signals the need for greater emphasis on summer habitats in land management planning on behalf of elk. © 2013 The Wildlife Society. Source

Cope J.M.,National Oceanic and Atmospheric Administration | Devore J.,Pacific Fishery Management Council | Dick E.J.,Southwest Fisheries Science Center | Ames K.,Pacific Fishery Management Council | And 7 more authors.
North American Journal of Fisheries Management

The Magnuson-Stevens Fishery Conservation and Management Act (MSA) requires active management of all stocks at risk of overfishing or otherwise in need of conservation andmanagement. In the Pacific Fishery Management Council groundfish fishery management plan, about two-thirds of the more than 90 managed stocks are currently without traditional assessments to help define stock status in relation to management targets. Stock complexes are often employed for management purposes in such situations. The guidelines issued in respons to the 2006 MSA amendments defined a complex as a group of stocks with similar geographic distributions, life histories, and vulnerabilities to fisheries. This work uses productivity-susceptibility analysis (PSA) to measure the vulnerabilities of 90 managed groundfish stocks, 64 of which are currently managed within stock complexes. These stock complexes are reevaluated by first using a partitioning cluster analysis to group the stocks by depth and latitude. Vulnerability reference points are then established based on the PSA results to determine vulnerability groups of low, medium, high, and major concern within each ecological group. This method is a simple and flexible approach to incorporating vulnerability measures into stock complex designations while providing information with which to prioritize stockand complex-specific management. © American Fisheries Society 2011. Source

Most traditional fisheries models have size or stage-age relationships as their foundation. Two long-established metrics used are FL and TL. Body length measurements are linked to age, maturity, and fecundity. Obtaining FL or TL measurements are not always convenient, especially for larger fish (>100 cm TL). Two skate species, Longnose Skate Raja rhina and Big Skate R. binoculata, were collected from commercial fishery landings along the coast of Washington State and length-length or width-length conversions were investigated for four metrics of size: TL, tail only length (TOL), interspiracular width (ISW), and interorbital width (IOW). Relationships between TL and alternative measures were examined using model II regression analyses and confirmed a strong linear relationship in all cases (R2 > 0.94). It is likely that both TL and TOL measures have errors due to worn-off tail portions; conversely, the ISW is nonlaborious and convenient to obtain. The ISW metric has a smaller coefficient of variation compared with IOW if we assume that both metrics have the same distribution of measurement errors. We recommend ISW as the preferred alternative metric in the assessment of large skate. The ISW will probably yield measurements that are equivalent, or potentially superior, to traditional metrics because the measurement is taken from body parts devoid of worn-off portions. © 2013 Copyright Taylor and Francis Group, LLC. Source

Buchanan J.B.,Cascadia Research Collective | Brady K.,8 Devonshire Road | Michaelis W.,8 Devonshire Road
Wader Study Group Bulletin

Red Knots Calidris canutus that migrate along the Pacific Flyway during spring are believed to belong to the roselaari subspecies, and in coastal Washington, USA, these knots aggregate in numbers not exceeded elsewhere in the flyway south of Alaska. In May 2010, as part of a continuing effort to investigate knot migration, including an effort to develop an estimate of abundance, we searched the northern areas of Grays Harbor and Willapa Bay, Washington, from airboats for flagged Red Knots originating from Baja California Sur, Mexico. We observed Red Knots roosting on sand or dredge-spoil islands, on estuarine shorelines, and at primary foraging areas. Red Knots were observed roosting primarily at shoreline and island locations, including sites that would not be available to them during extreme high tides or during storm events. The peak abundance of Red Knots occurred on 8 May, when 5,665 were in Grays Harbor and 1,314 in Willapa Bay. We documented 157 individually-marked Red Knots including 154 from Guerrero Negro, Baja California Sur, Mexico, one from the Yukon-Kuskokwim River Estuary in western Alaska, one from Wrangel Island, Russia, and one from Golfo de Santa Clara, Gulf of California, Mexico. We found a significant positive correlation between the dates of first observation of 43 individuals observed in both 2009 and 2010 (rs = 0.42, P = 0.005) and this may reflect different timing of individual or cohort movements. Space use by knots changed during the migration period, with early migrants generally using areas near shore and late-season migrants using areas farther from shore. We observed 15 hunting flights by Peregrine Falcons Falco peregrinus directed at Red Knots, but none of these was successful. Key subjects requiring additional investigation are identified. Source

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