Microhabitat use by blackbanded Emphasis Type="I

Authors: Brent E Henry Gary D Grossman

Publish Date: 2007/12/11

Volume: 83, Issue: 2, Pages: 171-182

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Abstract

We used underwater observations to quantify microhabitat use for blackbanded Percina nigrofaciata turquoise Etheostoma inscriptum and tessellated E olmsteadi darters in a 116 m reach of a Piedmont stream during 2001–2002 The sampling period and the previous 12 months were the first and second driest years on record respectively Spring 2002 had the greatest amount of available habitat and principal component analysis indicated that only one of three species pairs displayed significant differences in microhabitat use during this season Conversely in fall 2001 intermediate microhabitat availability all three species used significantly different microhabitats In general turquoise darters used areas with greater amounts of erosional substrata tessellated darters occurred over more depositional substrata and blackbanded darters utilized intermediate microhabitats During fall 2001 large blackbanded darters ≥55 mm SL occupied faster microhabitats with more erosional substrata and used a greater variety of depths than smaller conspecifics 40–55 mm In fall 2001 large turquoise darters ≥40 mm used deeper microhabitats with higher velocities and more erosional substrata than smaller individuals whereas the opposite was true ≤50 mm in faster more erosional than 50 mm in fall 2002 In general darters did not occur in microhabitats with significantly higher invertebrate abundances however both blackbanded and tessellated darters occupied microhabitats with higher percentages of Diptera in a single season The inconsistent responses of darters to microhabitat prey abundance may have been influenced by extreme drought conditionsWe would like to acknowledge the support of numerous friends and colleagues including Barbara Rachel and Anna Grossman Robert Ratajczak Tom Reinert Nolan Banish Mary and Bud Freeman Brenda Rashleigh John Johnston Ferrell Stamback Vera Goodson Marilyn Massey Dan Henry Stephanie Massey and Jamie Stark and the staff of Jittery Joe’s The manuscript benefited from the comments of Jim Peterson and C Rhett Jackson Funding for this project was provided by the US Environmental Protection Agency via a NNEMS fellowship to the senior author Additional funding was provided by the D B Warnell School of Forestry and Natural Resources This paper is dedicated to the memories of Dr Alan and Madison Mays

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