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Abstract (from http://www.tandfonline.com/doi/full/10.1080/02755947.2014.943860#.VJhyqUACo): Invasive Rainbow Smelt Osmerus mordax have been associated with reductions in Walleye Sander vitreusrecruitment, and predation by adult smelt on age-0 Walleyes has been identified as one of the potential mechanisms contributing to recruitment failure. Predation effects could be mitigated by stocking Walleye fingerlings based on smelt and Walleye morphometric relationships. By combining 0.95 quantile regression of smelt gape size on TL and 0.05 quantile regression of Walleye body depth on TL, we constructed a stocking tool to determine the appropriate size to stock Walleye fingerlings in lakes invaded by smelt such that few...
Abstract (from http://onlinelibrary.wiley.com/doi/10.1002/ecs2.1660/full): Empirically understanding spatial variation in secondary production rates is central to ecology. Yet for most taxa, such patterns are rarely examined, especially at different levels of ecological organization (e.g., species- vs. community-level patterns). We compiled data on biomass, production, and P/B rates of freshwater fish communities and species across latitudes and contrast patterns observed at the community level with those observed for species. At the community level, and at two distinct spatial scales (global vs. continental-North American), negative or neutral relationships were apparent between biomass, production, and P/B with...
Abstract (from Canadian Science Publishing): Managing fisheries through rapid environmental change requires diverse approaches for identifying and adapting to novel ecological conditions. For the Wisconsin Ceded Territory, we calculated 473 adult walleye (Sander vitreus) production (P), biomass (B), and P/B estimates for 1990–2012. Frequency distributions for production statistics were right-skewed, indicating the fishery is generally dominated by low production populations. Mean P, B, and P/B were significantly elevated in natural recruitment (NR) lakes compared with combination (NR + stocking) and stocked-only lakes. Furthermore, combination populations had significantly higher production compared with stocked-only...
Abstract: Processes that influence habitat selection in landscapes involve the interaction of habitat composition and configuration and are particularly important for species with complex life cycles. We assessed the relative influence of landscape spatial processes and local habitat characteristics on patterns in the distribution and abundance of spawning steelhead ( Oncorhynchus mykiss), a threatened salmonid fish, across ~15,000 stream km in the John Day River basin, Oregon, USA. We used hurdle regression and a multi-model information theoretic approach to identify the relative importance of covariates representing key aspects of the steelhead life cycle (e.g., site access, spawning habitat quality, juvenile...
Abstract (from http://link.springer.com/article/10.1007%2Fs12237-013-9694-0): Salt marsh faunas are constrained by specific habitat requirements for marsh elevation relative to sea level and tidal range. As sea level rises, changes in relative elevation of the marsh plain will have differing impacts on the availability of habitat for marsh obligate species. The Wetland Accretion Rate Model for Ecosystem Resilience (WARMER) is a 1-D model of elevation that incorporates both biological and physical processes of vertical marsh accretion. Here, we use WARMER to evaluate changes in marsh surface elevation and the impact of these elevation changes on marsh habitat for specific species of concern. Model results were compared...
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Information about these images can be found in the Final Report for Sea-level Rise Response Modeling for San Francisco Bay Estuary Tidal Marshes. Site-specific data are available by request. Contact: Dr. John Y. Takekawa, USGS Western Ecological Research Center, San Francisco Bay Estuary Field Station, 505 Azuar Dr. Vallejo, Calif. 94592, 707-562-2000
Abstract: Native freshwater mussels are long-lived, sessile, benthic invertebrates that may be extremely susceptible to elevated water temperatures because of their patchy distribution, limited dispersal and mobility, and larval dependence on fish. Recent research suggests that many species may be living close to their upper thermal limits and that some rivers have seen a shift in species composition to more thermally tolerant mussel species. We tested the hypothesis that elevated water temperatures (20, 25, 30, and 35°C) adversely affected the survival and physiology of juvenile mussels and physiology of adult mussels. In juveniles, the 28-d LT50s ranged from 25.3 to 30.3°C. H eart rate was significantly affected...
These publications exemplify the use of the data from this project, " A Land of Flowers on a Latitude of Deserts: Aiding Conservation and Management of Florida’s Biodiversity", by the broader scientific community.
Abstract: Understanding the consequences of anthropogenic change for migratory species is challenging because although they have evolved to cope with environmental uncertainty, migrants still rely on predictable relationships within and among habitats to make informed decisions. Calidris shorebirds rely on ephemeral wetlands during northward migration through mid-continental North America, where favorable habitat conditions are annually and regionally unpredictable and increasingly altered by land-use change. During spring 2013 and 2014, we assessed Calidris habitat use in the Rainwater Basin (RWB) and the Prairie Pothole Region (PPR) at both local and landscape scales. Although anthropogenic change has altered...
Water laws and drought plans are used to prioritize and allocate scarce water resources. Both have historically been human-centric, failing to account for non-human water needs. In this paper, we examine the development of instream flow legislation and the evolution of drought planning to highlight the growing concern for the non-human impacts of water scarcity. Utilizing a new framework for ecological drought, we analyzed five watershed-scale drought plans in southwestern Montana, USA to understand if, and how, the ecological impacts of drought are currently being assessed. We found that while these plans do account for some ecological impacts, it is primarily through the narrow lens of impacts to fish as measured...
This article is a product from the project "Can Mammals Mediate Climatically-Induced Vegetation Transitions in Alpine Ecosystems of the Western United States?". Abstract: It is very common that only presence data are available in ecological niche modeling. However, most existing methods for evaluating the accuracy of presence–absence (binary) predictions of species require presence–absence data. The aim of this study is to present a new method for accuracy assessment that does not rely on absence data. Two new statistics Fpb and Fcpb were derived based on presence–background data. With generated six virtual species, we used DOMAIN, generalized linear modeling (GLM), and maximum entropy (MAXENT) to produce different...
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This dataset includes the cover of creosote bush (Larrea tridentata)in 1989, 1995, 1999, 2005, and 2009 across southern Arizona. Cover was determined using sub-pixel classifications of two Landsat scenes from path 36, row 38 (centered on latitude: 31.7470, longitude: -111.3981) and path 37, row 38 (31.7470, -112.9431) that encompass Tucson, AZ.
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In the western U.S., rising temperatures and pronounced drought conditions pose significant challenges to public land managers. Widespread declines of multiple plant species have already been observed, providing insight into what the future could look like for vegetation in the region as conditions are projected to become warmer and drier. To understand how vulnerable western ecosystems are to drought, managers need to know which climatic and soil conditions cause habitats to change, and at what rate these changes may occur – important topics on which there is little available data. This project seeks to identify the vulnerability of habitats in the western U.S. to drought. Researchers will compare changes in...


map background search result map search result map Assessing the Vulnerability of Dryland Ecosystems to Drought in the Western U.S. Shifts in Creosote bush in southern Arizona, 1989 - 2009 Shifts in Creosote bush in southern Arizona, 1989 - 2009 Assessing the Vulnerability of Dryland Ecosystems to Drought in the Western U.S.