Hydrologic regimes and water temperatures are primary predictors of freshwater species occurrence. Although these variables have been demonstrated to be important in regulating species diversity at particular locations, whether species occurrences across lotic habitats within a single, relatively small watershed can predict the full geographic extent of a species is unclear. We use river reach estimates of streamflow and water temperature derived from a watershed‐scale hydrologic model, coupled with body size measures, to investigate whether the type and variability of thermal and hydrologic habitat used by fish species within the Mobile River Basin (MRB) can predict the overall geographic extent of occurrence (GEO) for these taxa. Locality data for 108 species of fishes within MRB, one of the most ecologically diverse watersheds in the United States, were intersected with streamflow and water temperature estimates to characterize minimum and maximum streamflow and water temperature conditions and thermal breadth (range of thermal conditions) occupied by each species. Among all species, variation in GEO was associated with variation in thermal breadth and body size. Thermal variables were also important predictors of variation in GEO among Cyprinidae. Flow variables were important predictors of variation in GEO for Centrarchidae, Ictaluridae, and Percidae and within
The Logan River watershed, located in Northern Utah, USA, consists of a relatively pristine, mountainous area that drains to a lower elevation, valley area influenced by both urban development and agriculture. The Logan River Observatory has been collecting aquatic (streamflow and water quality) and climate data throughout the Logan River watershed since 2014. While streamflow measurements are commonly made at the outlets of research watersheds, the Logan River watershed consists of diverse hydrologic, topographic, and geologic settings that require a detailed understanding of streamflow variability over time at many locations. Here, we illustrate: (a) the importance of collecting streamflow time series throughout complex watersheds, and (b) how simple flow balances can provide much needed hydrologic insight into the locations and timing of gains and losses over reaches to guide future investigations.
more » « less- Award ID(s):
- 2043363
- PAR ID:
- 10446503
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Hydrological Processes
- Volume:
- 35
- Issue:
- 8
- ISSN:
- 0885-6087
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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