Comparison of a small-mesh seine and a backpack electroshocker for evaluating fish populations in a north-central alabama stream

Academic Article

Abstract

  • A comparison of the sampling effectiveness of a backpack electroshocker and small-mesh seine was conducted on the upper Cahaba River in the Valley and Ridge physiographic province of north-central Alabama. Each of 15 sites was sampled once during fall 1995 (20 September–23 October), spring 1996 (2 May–20 June), and fall 1996 (20 September–16 October). Sampling was conducted with both gears on the same day, and the same amount of sampling time was allocated to each gear. Samples were segregated into seven groups (Cyprinidae, Catostomidae, Percidae, Centrarchidae [further subdivided into sunfish-crappie and bass categories], and other families as a group), and comparisons of the percent relative abundance (PRA) of groups were made between gears at each sampling station. The PRAs of the groups differed significantly between gears at all 15 stations. Cyprinid PRAs were consistently higher in seine collections, whereas percids, sunfish-crappie, and bass PRAs were higher in electroshocker collections. The seine collected more cyprinid species, the electroshocker more centrarchid species. No difference between gears was observed in the species richness of percids and catostomids collected. The abundances of species collected by each gear were significantly correlated at only one site, indicating that the gears were capturing species in different proportions. Use of both sampling gears in this ecoregion produced more complete samples in terms of species richness and abundance than either gear would have produced on its own. © 1998 American Fisheries Society.
  • Digital Object Identifier (doi)

    Author List

  • Onorato DP; Angus RA; Marion KR
  • Start Page

  • 361
  • End Page

  • 373
  • Volume

  • 18
  • Issue

  • 2