Northwest Science最新文献_第5页

Benthic Insect Assemblage and Species-Level Responses to Eleven Years of Nutrient Addition in the Kootenai River, Idaho 爱达荷州库特奈河底栖昆虫群落和物种水平对11年营养添加的响应

IF 0.4 4区环境科学与生态学

Northwest Science Pub Date : 2021-10-12 DOI: 10.3955/046.095.0105

Bahman Shafii, G. Minshall, Charles E. Holderman, P. Anders, W. Price

{"title":"Benthic Insect Assemblage and Species-Level Responses to Eleven Years of Nutrient Addition in the Kootenai River, Idaho","authors":"Bahman Shafii, G. Minshall, Charles E. Holderman, P. Anders, W. Price","doi":"10.3955/046.095.0105","DOIUrl":"https://doi.org/10.3955/046.095.0105","url":null,"abstract":"Abstract Because of their abundance and intermediate trophic level positions, benthic invertebrates can affect trophic dynamics in aquatic ecosystems by routing and regulating energy through aquatic food webs. Significant reductions in nutrient loading and primary production downstream from dams can profoundly affect benthic insect assemblages. The Kootenai River, a large 7th order river in Idaho, Montana, and British Columbia, experienced such changes following construction of Libby Dam in 1972. A nutrient addition program was initiated in 2005 to mitigate the resulting cultural oligotrophication. The goal of this study was to evaluate long-term responses to nutrient addition among benthic insects at the assemblage and species levels, using replicated data collected from 2003 to 2016, and classified into pre-, early post-, and late post-nutrient addition periods. Response metrics included total abundance and biomass measures across all species, as well as aggregated species of major insect orders, five functional feeding groups, and species richness. We also included abundance responses from a substantial number of individual Chironomidae, and non-Chironomidae insect species. Effects of nutrient addition were assessed using before-after-control-impact and before-and-after analyses. Spearman's Rank correlation coefficients were used to express the degree of association between biotic and abiotic factors. Nutrient addition consistently contributed to increased individual and total insect abundance each year for over a decade without inducing substantive changes in community composition or species dominance. Overall, benthic insects responded positively to nutrient addition and did so in a similar fashion in the early and late nutrient addition periods.","PeriodicalId":49743,"journal":{"name":"Northwest Science","volume":"95 1","pages":"73 - 97"},"PeriodicalIF":0.4,"publicationDate":"2021-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48661253","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

Status and Distribution: A Key to Bird Identification 现状与分布:鸟类鉴定的关键

IF 0.4 4区环境科学与生态学

Northwest Science Pub Date : 2021-10-12 DOI: 10.3955/046.095.0109

A. J. McCormick

引用次数: 0

Passive Restoration of a Small Mountain Stream in Eastern Oregon 俄勒冈州东部一条小山溪的被动修复

IF 0.4 4区环境科学与生态学

Northwest Science Pub Date : 2021-10-12 DOI: 10.3955/046.095.0104

A. Holthuijzen

{"title":"Passive Restoration of a Small Mountain Stream in Eastern Oregon","authors":"A. Holthuijzen","doi":"10.3955/046.095.0104","DOIUrl":"https://doi.org/10.3955/046.095.0104","url":null,"abstract":"Abstract In this study, I documented the results of 11 years of passive restoration of a small mountain stream in northeastern Oregon. Removal of the main stressors on the system, grazing and agricultural practices, resulted in a strong recovery of the riparian vegetation over the middle two-thirds of the reach. Cover of trees and shrubs tripled, tree density increased sevenfold, and stream shading fourfold over the period 2007 through 2018. Average maximum daily stream temperature declined by 2.1 to 2.8 °C, and average maximum diurnal temperature range narrowed by 3.7 to 4.6 °C. Recolonizing American beavers (Castor canadensis) played an essential role in improving the condition of the streambed over 18% of the reach. Their dams and ponds initiated the process of streambed aggradation and transformed the single-thread, incised channel into a multi-thread configuration within beaver complexes. Vegetation expansion was much stronger in impounded than in un-impounded parts of the stream. Passive restoration was not effective in two sections, together comprising one-third of the reach. In the upper part of the stream, recovery stalled because of continued (unauthorized) trespass grazing during late summer and fall. The channelized lower section of the stream was too severely modified for measurable recovery to occur. I concluded that 11 years of passive restoration improved the functionality of the stream from 24% to 32%, and within beaver complexes, up to 57% of its pre-disturbance condition.","PeriodicalId":49743,"journal":{"name":"Northwest Science","volume":"95 1","pages":"54 - 72"},"PeriodicalIF":0.4,"publicationDate":"2021-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43150099","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

Factors Affecting Angling Fight and Air Exposure Times for Yellow Perch, Smallmouth Bass, and Crappie in Lentic Fisheries 影响黄鲈、小嘴鲈鱼和鲷鱼钓鱼斗争和暴露时间的因素

IF 0.4 4区环境科学与生态学

Northwest Science Pub Date : 2021-05-21 DOI: 10.3955/046.094.0307

K. Meyer, Jeff C. Dillon, D. Schill

{"title":"Factors Affecting Angling Fight and Air Exposure Times for Yellow Perch, Smallmouth Bass, and Crappie in Lentic Fisheries","authors":"K. Meyer, Jeff C. Dillon, D. Schill","doi":"10.3955/046.094.0307","DOIUrl":"https://doi.org/10.3955/046.094.0307","url":null,"abstract":"Abstract The effects of catch-and-release related fight and air exposure times on post-release stress response or mortality of fishes has repeatedly been investigated, but rarely have anglers been observed to determine fight and air exposure times to which caught-and-released fish are actually exposed. We observed anglers land and either harvest or release yellow perch (Perca flavescens), smallmouth bass (Micropterus dolomieu), white crappie (Pomoxis annularis), and black crappie (P. nigromaculatus) to evaluate associated fight time and air exposure time. A total of 237 fight and 312 air exposure times were recorded; mean fight time was 10.1 s (range 1 to 40 s), mean air exposure of released fish was 20.1 s (range 2 to 141 s), and 95% of anglers subjected fish to < 24 s of fight time and < 51 s of air exposure. Landing crappie required less time (X̄ = 8.5 s) than landing yellow perch (X̄ = 12.8 s) or smallmouth bass (X̄ = 12.9 s). Air exposure was longer for yellow perch (X̄ = 28.1 s) and smallmouth bass (X̄ = 25.9 s) than for crappie (X̄ = 14.9 s), and small fish were subjected to less air (X̄ = 17.6 s) than larger fish (X̄ = 28.5 s). Results of the present study suggest that air exposure and fight times for warm-water and cool-water fish released by Idaho anglers are relatively short and therefore appear to be biologically inconsequential. Further work is needed to support or refute these findings for actual anglers across a larger geographic area.","PeriodicalId":49743,"journal":{"name":"Northwest Science","volume":"94 1","pages":"302 - 308"},"PeriodicalIF":0.4,"publicationDate":"2021-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42160828","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

Temporal Variability in Climate-Growth Response of Mountain Hemlock at Treeline in Washington and Oregon 华盛顿州和俄勒冈州林线山区铁杉气候-生长响应的时间变异

IF 0.4 4区环境科学与生态学

Northwest Science Pub Date : 2021-05-21 DOI: 10.3955/046.094.0306

Summer Kemp-Jennings, D. Peterson, A. Bunn

{"title":"Temporal Variability in Climate-Growth Response of Mountain Hemlock at Treeline in Washington and Oregon","authors":"Summer Kemp-Jennings, D. Peterson, A. Bunn","doi":"10.3955/046.094.0306","DOIUrl":"https://doi.org/10.3955/046.094.0306","url":null,"abstract":"Abstract Climate-growth relationships in altitudinal treeline forests are particularly informative because they represent the upper limit of a species range where growth is often especially sensitive to climatic variation. Radial growth response to climatic variables typically ranges from energy limited to water limited. In the Pacific Northwest region of North America, treeline forests are typically energy limited. Results from a recent study (Marcinkowski et al. 2015) indicate a change in climate-growth relationships over time in treeline mountain hemlock (Tsuga mertensiana) in northern Washington state. Here, we investigate whether these same relationships hold across 700 km of the range of treeline mountain hemlock in Oregon and Washington. Using cores from trees > 200 years old, we examined temporal and spatial variability of climate-growth relationships since the early 20th century. Results indicate 1) a potential weakening of energy limitation in forest growth at treeline, 2) a nonstationary growth response to climate variables through time, and 3) different patterns of growth response to climate from north to south. Climate-growth relationships were generally similar between different aspects in the same geographic location, with some exceptions. Correlations between climate variables and radial growth differ over time (ranging from significantly positive to significantly negative), indicating the non-stationary nature of climate-growth relationships. These results identify where changes in growth-limiting variables may be occurring at treeline. Additional changes in the effects of climate change on growth at treeline are expected, and may be temporally complex.","PeriodicalId":49743,"journal":{"name":"Northwest Science","volume":"94 1","pages":"286 - 301"},"PeriodicalIF":0.4,"publicationDate":"2021-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43971185","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: 3

Generous Lives: Oregon's Nature Stirs Hearts to Action 慷慨的生活:俄勒冈州的自然激发人们的行动

IF 0.4 4区环境科学与生态学

Northwest Science Pub Date : 2021-05-21 DOI: 10.3955/046.094.0308

R. Lawton

引用次数: 0

Tui Chub (Siphateles bicolor) are Native to the Columbia River Basin in Washington State Tui Chub（Siphateles bicolor）原产于华盛顿州哥伦比亚河流域

IF 0.4 4区环境科学与生态学

Northwest Science Pub Date : 2021-05-21 DOI: 10.3955/046.094.0303

Patrick M. Lubinski, A. T. Scholz

引用次数: 0

A Small Proportion of Breeders Drive American Bullfrog Invasion of the Yellowstone River Floodplain, Montana 一小部分繁殖者驱使美国牛蛙入侵蒙大拿州黄石河漫滩

IF 0.4 4区环境科学与生态学

Northwest Science Pub Date : 2021-05-21 DOI: 10.3955/046.094.0302

Daniel M. Bingham, Adam J. Sepulveda, S. Painter

{"title":"A Small Proportion of Breeders Drive American Bullfrog Invasion of the Yellowstone River Floodplain, Montana","authors":"Daniel M. Bingham, Adam J. Sepulveda, S. Painter","doi":"10.3955/046.094.0302","DOIUrl":"https://doi.org/10.3955/046.094.0302","url":null,"abstract":"Abstract The American bullfrog (Lithobates catesbeianus) is a non-native invader of aquatic habitats across the northwestern United States. It recently invaded the Yellowstone River, Montana, and has spread to over 140 km of floodplain habitat. We analyzed seven microsatellites in 528 tadpoles sampled across nearly the entire Yellowstone River invasion (about 140 river km) to characterize invasion genetics, compare our results with those of a recent mtDNA study (Kamath et al. 2016), and to inform control efforts. Microsatellite variation supports the mtDNA-based hypothesis of at least two independent introductions to the floodplain from genetically divergent populations in the midwestern United States, followed by massive range expansion. One introduction is associated with the upstream extent of the invasion near Park City, Montana and the other more broadly with downstream populations. All sites were characterized by small effective numbers of breeders (Nb; harmonic mean = 9.97), and therefore, a small proportion of highly successful adults may drive the invasion by producing large families. Microsatellites and mtDNA produced discordant estimates of genetic admixture between the upstream and downstream invasions, which may reflect small effective population size. Although we observed isolation by distance using both types of markers, microsatellites appear to reflect population structure resulting from secondary contact between the two introductions, as opposed to structure resulting from equilibrium between gene flow and genetic drift. Most sites showed evidence for genetic bottlenecks, which supports the recent history of invasion. Small Nb paired with known high localized extinction rates following colonization suggests focused removal of post metamorphic life stages at sites less likely to go extinct on their own could help limit invasion by bullfrogs.","PeriodicalId":49743,"journal":{"name":"Northwest Science","volume":"94 1","pages":"231 - 242"},"PeriodicalIF":0.4,"publicationDate":"2021-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49018560","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

Comparative Reproductive Ecology of Two Subspecies of Pacific Marten (Martes caurina) in California 加利福尼亚州太平洋马氏体两个亚种的比较繁殖生态学

IF 0.4 4区环境科学与生态学

Northwest Science Pub Date : 2021-05-21 DOI: 10.3955/046.094.0305

Matthew S. Delheimer, Katie M. Moriarty, K. Slauson, Alyssa M. Roddy, Desiree A. Early, Keith A. Hamm

{"title":"Comparative Reproductive Ecology of Two Subspecies of Pacific Marten (Martes caurina) in California","authors":"Matthew S. Delheimer, Katie M. Moriarty, K. Slauson, Alyssa M. Roddy, Desiree A. Early, Keith A. Hamm","doi":"10.3955/046.094.0305","DOIUrl":"https://doi.org/10.3955/046.094.0305","url":null,"abstract":"Abstract Accurate information on reproductive ecology is necessary to develop conservation actions for at-risk wildlife species. Our objective was to describe female reproductive parameters and den use of two subspecies of wild, untrapped Pacific martens (Humboldt marten, Martes caurina humboldtensis; Sierran marten, M. c. sierrae) of conservation interest in California. We used radio telemetry and remotely triggered cameras to monitor 10 Humboldt martens (2014 to 2016) and six Sierran martens (2016 to 2017) over 23 total denning periods. For Humboldt martens, mean parturition date was 13 April, proportion of adult females reproducing was 80% (n = 12 of 15), and mean litter size was 1.8 ± 0.6 kits (x̄ ± SD). For Sierran martens, mean parturition date was 29 April, proportion of adult females reproducing was 87% (n = 7 of 8), and mean litter size was 1.9 ± 0.7 kits. Humboldt and Sierran marten dens were predominantly located in woody structures, with live trees, snags, and logs comprising 91% and 79% of dens, respectively. Although reproductive ecologies of Humboldt and Sierran martens were largely similar, Sierran marten parturition dates were significantly later. We compare our study populations to other North American marten populations and examine factors that could influence consistency or variability in reproductive parameters between populations.","PeriodicalId":49743,"journal":{"name":"Northwest Science","volume":"94 1","pages":"271 - 285"},"PeriodicalIF":0.4,"publicationDate":"2021-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43482366","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: 4

Establishment and Survival of Subalpine Fir (Abies lasiocarpa) in Meadows of Olympic National Park, Washington 华盛顿奥林匹克国家公园草地亚高山冷杉(Abies lasiocarpa)的建立和生存

IF 0.4 4区环境科学与生态学

Northwest Science Pub Date : 2021-05-21 DOI: 10.3955/046.094.0304

A. Woodward, Jonathan A. Soll

{"title":"Establishment and Survival of Subalpine Fir (Abies lasiocarpa) in Meadows of Olympic National Park, Washington","authors":"A. Woodward, Jonathan A. Soll","doi":"10.3955/046.094.0304","DOIUrl":"https://doi.org/10.3955/046.094.0304","url":null,"abstract":"Abstract Establishment of trees in subalpine meadows is a potential indicator of ecological effects of climate change. Tree establishment is a multi-year process including cone and seed production, germination, establishment, and growth, with each demographic step possibly sensitive to different climate limitations. While most studies have focused on one or a few steps, this study follows a cohort of individually marked saplings for 27 years beginning as seeds in two meadows on Hurricane Ridge, Olympic National Park. These meadows are examples of a south-facing tall sedge community type rather than the north-facing heath-shrub type where establishment has usually been observed. Results showed that mortality was high for the first few years, but number of saplings stabilized after the first decade. Seedling mortality during germination and establishment was directly related to weather that resulted in high air and soil temperatures and drought, while mortality of established saplings was indirectly related to weather through effects on growth. Growth was enhanced by longer growing season and warmer minimum temperatures; growth over three years and sapling height were predictive of mortality. Most sapling survival occurred in lichen (primarily Trapeliopsis granulosa) and Vaccinium deliciosum plant communities. Many saplings are growing at very low rates compared with the rate predicted from adult trees. It is also apparent that while microsite within meadow (e.g., relative snow depth) is important in determining sapling success, the landscape position of meadows (e.g., north versus south aspect) exerts a higher-level control over whether a subalpine meadow is likely to disappear with warming climate.","PeriodicalId":49743,"journal":{"name":"Northwest Science","volume":"94 1","pages":"256 - 270"},"PeriodicalIF":0.4,"publicationDate":"2021-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47509710","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