Morphology and its Effect on Habitat Selection of Stream Fishes

Abstract

Fishes were sampled in the Mississinewa, Salamonie, Wabash, and White rivers, Indiana to determine whether fish depth ratio (maximum depth/total length) varied between pool and riffle habitats. Fish collections were made using a backpack electrofisher and water velocity measurements were made using a flow meter. Our results indicated median depth ratio differed between fishes located in pool habitats (0.28) compared to fishes in riffle habitats (0.17). These depth ratio findings were consistent among all four rivers, showing fish morphology is related to habitat selection and use. Changes in fish community structure would be expected with habitat changes in flow regimes, either through natural or anthropogenic (e.g., channelization) alterations.