Effect of Electrofishing Effort on an Index of Biotic Integrity

Abstract

We sampled fishes at 15 stream sites in the Ozark Highlands ecoregion of Arkansas and examined the effects of sampling effort on an index of biotic integrity (IBI). We found that sampling effort affected component metric scores, IBI scores, and qualitative site classifications. The scores of taxonomic richness metrics increased with increasing effort, while relative abundance metrics were inconsistently affected by sampling effort. The scores of all metrics stabilized with increasing effort. Although some deviation from the sampling effort designated for the IBI appeared acceptable, we found that even a sampling effort deviation of 10 mean stream widths from the designated effort (19.6%) caused one qualitative site classification to change. Our results showed that differences in sampling effort can affect IBI scores and result in erroneous stream assessments. They also indicated that an accurate assessment of regional stream conditions relies on incorporating the specific sampling effort designated for the Ozark Highlands IBI.

The influence of drought on flow‐ecology relationships in Ozark Highland streams

“…Fish and crayfish were collected using a Smith‐Root Model LR‐24 backpack electrofishing unit which has been shown to be effective for sampling fish and crayfish assemblages in Ozark streams (Dauwalter & Pert, ; Rabeni, Collier, Parkyn, & Hicks, ). Standard LR‐24 settings for power output based on ambient stream conductivity were used.…”

An Evaluation of Qualitative Indexes of Physical Habitat Applied to Agricultural Streams in Ten U.S. States1

“…(2006) and Hughes and Peck (2008). Sites of that length were generally found adequate for assessing fish species richness in wadeable streams throughout the U.S. (Lyons, 1992; Angermeier and Smogor, 1995; Paller, 1995; Dauwalter and Pert, 2003b) and for repeatable index of biotic integrity (IBI) estimates (Dauwalter and Pert, 2003a; Reynolds et al. , 2003).…”

Assemblage level monitoring of stream fishes: The relative efficiency of single-pass vs. double-pass electrofishing

“…Since the number of groups within an ecological guild metric (e.g. number of trophic groups) must be always lower than the total number of species, lower sampling effort is required for their estimation at a standardized level of accuracy and precision than the effort used for species richness or compositional data (Bady et al, 2005;Dauwalter and Pert, 2003b;Hughes and Herlihy, 2007;Maret et al, 2007;Erős et al, 2008).…”