Trait Compositions of Fish Assemblages across Hydrologic Regimes

Role of Geodata Crawler:
Geodata Crawler was used to quantify watershed characteristics (land cover, soils, topography, etc.) at over 2,000 stream locations where historical fish data were available from state agencies and universities. Watershed characteristics were used to estimate natural hydrology in these streams that were then related to life history strategies and spawning characteristics of fish in these communities.

Bruckerhoff LA, Leasure DR, Magoulick DD. 2016. Trait Composition of Fish Assemblages across Hydrologic Regimes in The Role of Hydrologic Regimes in Driving Morphologic Divergence and the Trait Compositions of Fish Assemblages. MS Thesis. University of Arkansas, Fayetteville, Arkansas, USA.

Funding Source:
USGS Cooperative Fish and Wildlife Research Unit, Dept. of Biological Sciences, University of Arkansas

Contribution to Education:
M.S. Thesis (in review) by Lindsey Bruckerhoff in the Dept. of Biological Sciences at the University of Arkansas.

Establishing ecological-flow relationships is a crucial component of managing lotic systems within an environmental flow framework. Species traits may be useful for developing ecological-flow relationships because they can be used to make comparisons across biogeographical boundaries. Fish traits, such as life history strategies and spawning characteristics, have been linked to hydrologic metrics and classified flow regimes at relatively large spatial scales, but not smaller, management level scales, and the role of spatial autocorrelation in driving trait distributions in stream networks has not been assessed. We used combined fourth-corner and RLQ analysis and mixed moving average spatial stream network (SSN) models to (1) determine the relationship between fish traits and hydrologic metrics within classified flow regimes at a management (state) level spatial scale, (2) determine how traits are spatially auto-correlated within a stream network, and (3) compare the degree of spatial autocorrelation between flow regimes. The strength of relationships between fish traits and hydrologic metrics were relatively strong in groundwater and runoff streams, while relationships were weak in intermittent streams. Relationships between fish traits and flow metrics were often different between flow regimes. Spatial factors described more variability in the distribution of fish traits than hydrologic metrics within and between flow regimes and different types of spatial autocorrelation structured trait patterns across flow regimes. This study highlights the complex relationships between biota and hydrologic regimes and the importance of considering spatial patterns when developing ecological-flow relationships.

Professional Presentations:
2016 (Accepted). American Fisheries Society Annual Meeting, Kansas City, MO.
2016 (Accepted). Joint Meeting of Ichthyologists and Herpetologists, New Orleans, LA.
2016 Arkansas Fish and Wildlife Research Unit Cooperators Meeting, Fayetteville, AR.
2015 American Fisheries Society Annual Meeting, Portland, OR.