The Mid-Atlantic region is a hot spot for stream habitat restoration in degraded watersheds yet few studies have determined whether the fish assemblage would respond to restoration practices. I tested effects of instream habitat enhancement through fish selection response using three treatments (woody debris - LWD, shade - SH, and both - SHWD) in first order urban (> 60% urban land use, ULU), suburban (27-46% ULU), and rural (< 15% ULU) eastern Piedmont streams in Maryland (n = 36). Twenty meter block-netted experimental segments were split into combinations of one enhancement section (10 m) paired with a control section (10 m). Fish were removed by double-pass electrofishing, treatments were constructed and only Rhinichthys atratulus and Semotilus atromaculatus were replaced into the center of the segment. For 6 h the fish were allowed to range freely between sections, then treatment and control sections were separated by a blocknet and fish were retrieved and tallied. Habitat selection was significantly different between rural SHWD vs. LWD, and between SHWD and SH in suburban fish (P < 0.05). Fish total length differed significantly between urban, suburban, and rural fish, where urban fish were the smallest (P < 0.05). CKB who selected the treatment were significantly larger than in the control section (P < 0.05). Size-dependent habitat segregation may occur as a result of intraspecific competition. Rural and suburban fish recognized and selected the most complex stream habitat enhancements, yet urban fish most commonly selected SH. Thus, increasing the amount of overhead cover in urban stream channels would be beneficial for fish populations when implementing stream restoration practices.
