Determining a Regional Framework for Assessing Biotic Integrity of Virginia Streams

Abstract

The utility of an index of biotic integrity (IBI) depends on its ability to distinguish anthropogenic effects on biota amid natural biological variability. To enhance this ability, we examined fish assemblage data from least‐disturbed stream sites in Virginia to determine the best way to regionally stratify natural variation in candidate IBI metrics and their scoring criteria. Specifically, we examined metric variation among physiographic regions, U.S. Environmental Protection Agency ecoregions, and drainage basins to judge their utility as regions in which to develop and use distinct versions of the IBI for Virginia warmwater streams. Statewide, metrics differed most among physiographic regions; thus, we recommend their use as IBI regions. Largest differences were found for taxonomic metrics between coastal plain and mountain sites, particularly in numbers of native minnow (Cyprinidae), sunfish (Centrarchidae), and darter (Percidae) species. Trophic and reproductive metrics also differed between coastal plain and more‐upland streams, presumably reflecting differences in functional adaptations of fishes to upland versus lowland stream habitats. We suggest three preliminary regional IBIs for Virginia, each having a distinctive set of taxonomic, trophic, and reproductive metrics and corresponding scoring criteria.

Habitat relationships with fish assemblages in minimally disturbed Great Plains regions

“…1986; Harris & Silveira 1999), quantifying intensity of disturbance (Mebane 2001), and determining natural variation in fish communities (Karr et al. 1986; Schlosser 1990; Smogor & Angermeier 2001). Additionally, these systems are important to assessing restoration efforts (Hughes et al.…”

Influence of Non-point Source Pollution on Riverine Fish Assemblages in South West France

“…This is a standard result because both temperature and flow play critical roles in structuring fish assemblages in rivers (Matthews, 1998;Jackson et al, 2001). The dummy variable being significant confirms that fish assemblages are related to the physiography of the landscape (Resh et al, 1988;Smogor and Angermeier, 2001). As stated above, NSP has its origin in land use, mainly from both agricultural activities and urbanization in a watershed (Wang et al, 1997;Harding et al, 1998;.…”

“…A dummy variable was included in order to assess whether regional heterogeneity in the basin had an effect on the models. Resh et al (1988) and Smogor and Angermeier (2001) noted that both natural and human disturbances in rivers have different consequences according to the physiography of the watershed (i.e. mountains, piedmont or floodplain).…”

Use of the Coefficient of Community Loss (I) to Assess Cultural Stresses on Monongahela River Tributary Fish Communities

“…But in some cases, authors found ambiguous or positive relationships between agricultural land use and IBI scores (Gordon andMajumder 2000, Couch 1997). Because the metrics used in these indices represent a variety of trophic levels, taxonomic groups, functional characteristics, and tolerance ranges, modifications must often be made to reflect regional or local characteristics (Fausch et al 1984, Karr et al 1986, Barbour et al 1999, McCormick et al 2001, Smogor and Angermeier 2001. Such modifications limit the comparability of these studies across landscapes.…”