Northwest Science最新文献_第8页

Salmonid Habitat and Population Capacity Estimates for Steelhead Trout and Chinook Salmon Upstream of Scott Dam in the Eel River, California 加州鳗鱼河斯科特水坝上游钢头鳟鱼和支努克鲑鱼的栖息地和种群容量估算

IF 0.4 4区环境科学与生态学

Northwest Science Pub Date : 2020-04-22 DOI: 10.3955/046.094.0106

Emily J. Cooper, A. O’Dowd, J. Graham, D. Mierau, W. Trush, Ross Taylor

{"title":"Salmonid Habitat and Population Capacity Estimates for Steelhead Trout and Chinook Salmon Upstream of Scott Dam in the Eel River, California","authors":"Emily J. Cooper, A. O’Dowd, J. Graham, D. Mierau, W. Trush, Ross Taylor","doi":"10.3955/046.094.0106","DOIUrl":"https://doi.org/10.3955/046.094.0106","url":null,"abstract":"Abstract Estimating salmonid habitat capacity upstream of a barrier can inform priorities for fisheries conservation. Scott Dam in California's Eel River is an impassable barrier for anadromous salmonids. With Federal dam relicensing underway, we demonstrated recolonization potential for upper Eel River salmonid populations by estimating the potential distribution (stream-km) and habitat capacity (numbers of parr and adults) for winter steelhead trout (Oncorhynchus mykiss) and fall Chinook salmon (O. tshawytscha) upstream of Scott Dam. Removal of Scott Dam would support salmonid recovery by increasing salmonid habitat stream-kms from 2 to 465 stream-km for steelhead trout and 920 to 1,071 stream-km for Chinook salmon in the upper mainstem Eel River population boundaries, whose downstream extents begin near Scott Dam and the confluence of South Fork Eel River, respectively. Upstream of Scott Dam, estimated steelhead trout habitat included up to 463 stream-kms for spawning and 291 stream-kms for summer rearing; estimated Chinook salmon habitat included up to 151 stream-kms for both spawning and rearing. The number of returning adult estimates based on historical count data (1938 to 1975) from the South Fork Eel River produced wide ranges for steelhead trout (3,241 to 26,391) and Chinook salmon (1,057 to 10,117). An approach that first estimated juvenile habitat capacity and then used subsequent life stage survival rates yielded 1,281 (CV 56%) steelhead trout and 4,593 (CV 34%) Chinook salmon returning adults. Variability in estimated fish numbers reflects application of densities and survival rates from other populations, assumptions about salmonid productivity in response to potential spawning habitat capacity, residency and outmigration of early life-stages, summertime water quality conditions, and inter-annual hydrograph, marine, and population variability.","PeriodicalId":49743,"journal":{"name":"Northwest Science","volume":"94 1","pages":"70 - 96"},"PeriodicalIF":0.4,"publicationDate":"2020-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42002743","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

A Long-Awaited Key for the Grasses of Oregon and Washington 俄勒冈州和华盛顿州草原上等待已久的钥匙

IF 0.4 4区环境科学与生态学

Northwest Science Pub Date : 2020-04-22 DOI: 10.3955/046.094.0107

R. Halvorson

引用次数: 0

Tardigrades in the Forest Canopy: Associations with Red Tree Vole Nests in Southwest Oregon 森林冠层中的缓步动物:与俄勒冈州西南部红树田鼠巢的关系

IF 0.4 4区环境科学与生态学

Northwest Science Pub Date : 2020-04-22 DOI: 10.3955/046.094.0102

J. Villella, Jesse E. D. Miller, Alexander R. Young, Greg Carey, Andrew Emanuels, W. R. Miller

{"title":"Tardigrades in the Forest Canopy: Associations with Red Tree Vole Nests in Southwest Oregon","authors":"J. Villella, Jesse E. D. Miller, Alexander R. Young, Greg Carey, Andrew Emanuels, W. R. Miller","doi":"10.3955/046.094.0102","DOIUrl":"https://doi.org/10.3955/046.094.0102","url":null,"abstract":"Abstract Tardigrades live in many ecosystems, but local dispersal mechanisms and the influence of ecological gradients on tardigrade communities are not fully understood. Here we examine tardigrade communities in nests of the red tree vole (Arborimus longicaudus True), an arboreal mammal occupying the canopy of coniferous forests in western Oregon and northwestern California. We found 12 species of tardigrades from resin ducts sampled from 43 nests along a transect that spanned the east-west range of the red tree vole in southern Oregon. Tardigrade occurrence was more likely in larger trees and species numbers were significantly higher in areas that received more precipitation. At sites where they occurred, tardigrades were more abundant in red tree vole nests at greater heights within the forest canopy. Of the 12 species of tardigrades that were found, seven have not been previously reported in Oregon. Our results suggest that tardigrades in forest canopies in the Pacific Northwest are affected by regional precipitation gradients as well as local environmental variables, and that nest building by small mammals may facilitate dispersal of tardigrades within the forest canopy.","PeriodicalId":49743,"journal":{"name":"Northwest Science","volume":"94 1","pages":"24 - 30"},"PeriodicalIF":0.4,"publicationDate":"2020-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43051339","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

Inside Front Cover 封二

IF 0.4 4区环境科学与生态学

Northwest Science Pub Date : 2020-04-22 DOI: 10.3955/046.094.0109

引用次数: 0

Insect Visitors of Sidalcea hickmanii ssp. petraea (Malvaceae) and Their Effect on Flower, Fruit, and Seed Production 山菖蒲的访虫者。锦葵属植物及其对花、果、种生产的影响

IF 0.4 4区环境科学与生态学

Northwest Science Pub Date : 2020-04-22 DOI: 10.3955/046.094.0105

C. S. Ferguson, P. Schroeder, K. Donham, Marcia L. Wineteer

{"title":"Insect Visitors of Sidalcea hickmanii ssp. petraea (Malvaceae) and Their Effect on Flower, Fruit, and Seed Production","authors":"C. S. Ferguson, P. Schroeder, K. Donham, Marcia L. Wineteer","doi":"10.3955/046.094.0105","DOIUrl":"https://doi.org/10.3955/046.094.0105","url":null,"abstract":"Abstract This study sought to document potential insect pollinators of Neil Rock checkerbloom, Sidalcea hickmanii ssp. petraea (Malvaceae) and measure the effects of pollinator exclusion and plant type on flower, fruit, and seed production. Prior to this study, the pollination requirements of this gynodioecious plant were unknown and potentially complicated by its hermaphroditic and female-only plant types. Analyses showed that pollinator exclusion had no effect on mean number of flowers produced per raceme but significantly reduced the mean number of fruits produced per raceme and mean number of fruits produced per flower, as well as the mean number of seeds produced per raceme in both female-only and hermaphroditic plants. These results suggested that S. hickmanii ssp. petraea is pollinator dependent. Six orders (Hymenoptera, Coleoptera, Homoptera, Lepidoptera, Diptera, and Hemiptera) representing 29 taxa of insects (primarily Hymenoptera – notably Osmia and Hoplitis, and Coleoptera – notably Anthonomus and Trichodes) were collected from flowering S. hickmanii ssp. petraea plants. Adult Anthonomus weevils were observed selectively feeding on the developing fruits of hermaphroditic over female-only plants. This selective predation may have a significant impact on the maintenance of gynodioecy in this endemic, narrowly-isolated subspecies of Sidalcea hickmanii.","PeriodicalId":49743,"journal":{"name":"Northwest Science","volume":"152 2","pages":"62 - 69"},"PeriodicalIF":0.4,"publicationDate":"2020-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41291247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Exploiting the Winter Trophic Relationship between Weasels (Mustela spp.) and their Microtine Prey as a Survey Method for Weasels in Meadow Ecosystems 利用黄鼠狼与猎物间的冬季营养关系作为草甸生态系统黄鼠狼的调查方法

IF 0.4 4区环境科学与生态学

Northwest Science Pub Date : 2020-01-28 DOI: 10.3955/046.093.0303

W. Zielinski, M. Linnell, M. Schwartz, Kristy P. Pilgrim

{"title":"Exploiting the Winter Trophic Relationship between Weasels (Mustela spp.) and their Microtine Prey as a Survey Method for Weasels in Meadow Ecosystems","authors":"W. Zielinski, M. Linnell, M. Schwartz, Kristy P. Pilgrim","doi":"10.3955/046.093.0303","DOIUrl":"https://doi.org/10.3955/046.093.0303","url":null,"abstract":"Abstract Weasels can be important components of grassland and meadow communities where they influence the dynamics of small mammal populations which, in turn, can be keystone species in these communities. We evaluate a method for detecting and identifying two species of North American mustelines (i.e., Mustela frenata and M. erminea) in mountain meadow systems. It is based on previous knowledge that weasels often co-opt the winter nests of their vole (or lemming) prey and frequently deposit scats there. We exploit this aspect of the predator-prey relationship and describe how, when paired with genetic identification of species from scat, searching after spring melt for weasel scats in winter-constructed vole nests may be an alternative survey method for detecting weasels in meadows. Our work was conducted at the Sagehen Experimental Forest in the Sierra Nevada Mountains. We discovered and examined 90 winter vole nests over four spring seasons, resulting in an average (SD) of 3.31 (1.81) nests found per survey hour per year. From these nests we collected an average of 0.57 (0.37) putative weasel scats per survey hour. Of the seven scats that were verified to be from a weasel, five were from M. frenata and two from M. erminea. This was a proof of concept effort, to which we conclude that searches of vole nests for scat that can be genetically verified as weasel should have a place in the biologist's toolkit. The method is likely to be the most efficient for obtaining a genetic sample for weasels in mountain meadow systems.","PeriodicalId":49743,"journal":{"name":"Northwest Science","volume":"93 1","pages":"185 - 192"},"PeriodicalIF":0.4,"publicationDate":"2020-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43644297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Changes in Primary Producer and Consumer Communities in Response to Upstream Nutrient Addition in the Kootenai River, Idaho 库特奈河上游养分添加对初级生产者和消费者群落的影响

IF 0.4 4区环境科学与生态学

Northwest Science Pub Date : 2020-01-28 DOI: 10.3955/046.093.0306

G. Kruse, Bahman Shafii, Genevieve M. Hoyle, Charlie Holderman, P. Anders

{"title":"Changes in Primary Producer and Consumer Communities in Response to Upstream Nutrient Addition in the Kootenai River, Idaho","authors":"G. Kruse, Bahman Shafii, Genevieve M. Hoyle, Charlie Holderman, P. Anders","doi":"10.3955/046.093.0306","DOIUrl":"https://doi.org/10.3955/046.093.0306","url":null,"abstract":"Abstract The purpose of this study was to assess potential effects of nutrient addition in the previously unassessed lower Kootenai River (Meander Reach), 44–155 km downstream from the nutrient dosing site. We hypothesized that downstream periphyton and plankton densities would increase due to nutrient spiraling and organismal drift following seasonal upstream nutrient addition. Liquid inorganic ammonium polyphosphate fertilizer (10:34:0, N:P:K) was added to the Kootenai River in Idaho immediately downstream from the Idaho-Montana border with an in-river target concentration of 3.0 µg L-1 total dissolved phosphorus for 16 weeks (01 June–01 October) from 2006 through 2012. As predicted, mean periphyton, phytoplankton, and zooplankton densities increased significantly (P < 0.05) post-nutrient addition. Periphyton density increased 5.1 times (pre: 685.1 mm-2, post: 3501.0 mm-2), phytoplankton densities increased 1.7 times (pre: 1775.9 L-1, post: 3005.4 L-1), and zooplankton densities increased by 49% (pre: 67.0 L-1, post: 99.7 L-1). While nutrient uptake, water chemistry, algal and chlorophyll accrual, periphyton, macroinvertebrate, and native fish community responses to nutrient addition have been previously published, including results from upstream reaches of the Kootenai River, this study provides the first published account of lower trophic level responses at considerable distances downstream from the dosing site in altered, low velocity habitats which are very different from the upstream gravel-bed reaches reported in other studies. Results of this study add to the growing body of empirical knowledge regarding the use of nutrient addition for restoring large culturally denutrified rivers in the Pacific Northwest and provide valuable new insights regarding the longitudinal patterns of response magnitude.","PeriodicalId":49743,"journal":{"name":"Northwest Science","volume":"93 1","pages":"226 - 243"},"PeriodicalIF":0.4,"publicationDate":"2020-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45342622","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Short-Term Stream and Riparian Responses to Beaver Dam Analogs on a Low-Gradient Channel Lacking Woody Riparian Vegetation 在缺乏木质河岸植被的低坡度河道上，海狸坝对河流和河岸的短期响应

IF 0.4 4区环境科学与生态学

Northwest Science Pub Date : 2020-01-28 DOI: 10.3955/046.093.0302

M. Orr, Nicholas P. Weber, Wesley N. Noone, Megan G. Mooney, Taiontorake M. Oakes, Heather M. Broughton

{"title":"Short-Term Stream and Riparian Responses to Beaver Dam Analogs on a Low-Gradient Channel Lacking Woody Riparian Vegetation","authors":"M. Orr, Nicholas P. Weber, Wesley N. Noone, Megan G. Mooney, Taiontorake M. Oakes, Heather M. Broughton","doi":"10.3955/046.093.0302","DOIUrl":"https://doi.org/10.3955/046.093.0302","url":null,"abstract":"Abstract As ecosystem engineers, beavers (Castor canadensis) influence biogeomorphology and riparian vegetation. Streams with historic beaver removal and grazing often become incised, thereby altering stream and riparian processes. Anthropogenic structures that mimic beaver dams called beaver dam analogs (BDAs) may reverse incision by reintroducing historic processes. To understand BDAs as a process-based restoration tool, monitoring is needed across a range of watershed and stream conditions, but monitoring lags behind implementation. We constructed five BDAs in Central Oregon, on a low-gradient stream to test whether it may transport sufficient sediment to favor streambed aggradation behind BDAs. The stream also lacks woody riparian vegetation, and we examined how water temperatures and restoration plantings respond to BDAs where woody riparian vegetation is absent. We monitored structure integrity, aggradation, water temperature, groundwater, and vegetation for 1–2 yr after structures were installed. BDAs retained flows equally whether they were constructed from on-site juniper or off-site willow. During high flows, three structures failed and were rebuilt using improved design. After one year, aggradation of sediment above the two structures that survived flooding was negligible at one structure and high (33.7 m3) at the other. Groundwater levels rose 18–30 cm up to 135 m upstream of BDAs and 12 m into the floodplain. We found no evidence that BDAs raised stream temperatures. Within six months, willow cuttings planted near BDAs exhibited 1.3 times more growth than those on unimpounded locations. Overall, BDAs promoted a restoration trajectory on a low-gradient stream lacking woody riparian vegetation.","PeriodicalId":49743,"journal":{"name":"Northwest Science","volume":"93 1","pages":"171 - 184"},"PeriodicalIF":0.4,"publicationDate":"2020-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48368890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 8

A Scientific Chronicle of Pacific Salmon and Their Ecosystems 太平洋鲑鱼及其生态系统的科学编年史

IF 0.4 4区环境科学与生态学

Northwest Science Pub Date : 2020-01-28 DOI: 10.3955/046.093.0309

R. Bellmore

引用次数: 0

The Blues—A Diverse, Visually Appealing, and Thoughtfully Written Natural History of the Blue Mountains 蓝调——一部多样化的、视觉上吸引人的、深思熟虑的蓝山自然史

IF 0.4 4区环境科学与生态学

Northwest Science Pub Date : 2020-01-28 DOI: 10.3955/046.093.0308

P. Pringle

引用次数: 0