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Title: Predicting fine-scale distributions of peripheral aquatic species in headwater streams

Headwater species and peripheral populations that occupy habitat at the edge of a species range may hold an increased conservation value to managers due to their potential to maximize intraspecies diversity and species' adaptive capabilities in the context of rapid environmental change. The southern Appalachian Mountains are the southern extent of the geographic range of native Salvelinus fontinalis and naturalized Oncorhynchus mykiss and Salmo trutta in eastern North America. In this paper, we predicted distributions of these peripheral, headwater wild trout populations at a fine scale to serve as a planning and management tool for resource managers to maximize resistance and resilience of these populations in the face of anthropogenic stressors. We developed correlative logistic regression models to predict occurrence of brook trout, rainbow trout, and brown trout for every interconfluence stream reach in the study area. A stream network was generated to capture a more consistent representation of headwater streams. Each of the final models had four significant metrics in common: stream order, fragmentation, precipitation, and land cover. Strahler stream order was found to be the most influential variable in two of the three final models and the second most influential variable in the other model. Greater than 70%more » presence accuracy was achieved for all three models. The underrepresentation of headwater streams in commonly used hydrography datasets is an important consideration that warrants close examination when forecasting headwater species distributions and range estimates. Finally and additionally, it appears that a relative watershed position metric (e.g., stream order) is an important surrogate variable (even when elevation is included) for biotic interactions across the landscape in areas where headwater species distributions are influenced by topographical gradients.« less
 [1] ;  [1] ;  [2] ;  [1]
  1. North Carolina State Univ., Raleigh, NC (United States). College of Natural Resources. Center for Geospatial Analytics
  2. North Carolina State Univ., Raleigh, NC (United States). U.S. Geological Survey. North Carolina Cooperative Fish and Wildlife Research Unit
Publication Date:
OSTI Identifier:
Accepted Manuscript
Journal Name:
Ecology and Evolution
Additional Journal Information:
Journal Volume: 5; Journal Issue: 1; Journal ID: ISSN 2045-7758
Research Org:
North Carolina State Univ., Raleigh, NC (United States)
Sponsoring Org:
US Fish and Wildlife Service; USGS
Country of Publication:
United States
59 BASIC BIOLOGICAL SCIENCES; conservation planning; habitat modeling; headwater streams; landscape variables; peripheral populations; species distributions; topographic gradient; wild trout