Development and Evaluation of a Fish Assemblage Index of Biotic Integrity for Northwestern Great Plains Streams

Abstract

Quantitative indicators of biological integrity are needed for streams in the Great Plains of North America, but it was not known whether the index of biotic integrity (IBI) approach would be effective in this semiarid region. Great Plains streams have a depauperate and tolerant ichthyofauna and highly variable physicochemical conditions that may mask the effects of non‐point‐source pollution and stream habitat degradation. We developed an IBI based on fish assemblages by screening metrics for range, responsiveness to human influence, precision, and lack of redundancy; we then tested the IBI's ability to detect anthropogenic effects by validating the index with an independent data set. The IBI was composed of 10 metrics based on species richness and composition, trophic and reproductive guilds, and age structure. These 10 metrics had many significant correlations with substrate and water chemistry variables but had fewer significant correlations with riparian condition and watershed variables. Of the watershed variables, road density had the highest number of significant correlations with final IBI metrics. The IBI was validated by demonstrating its responsiveness to aggregate measures of human influence, site‐level habitat, and water chemistry, and its lack of responsiveness to factors that varied naturally, such as stream size and site elevation. The IBI was also temporally stable within and between years during repeat visits to a subset of sampled reaches. This IBI can be used as a measure of biological integrity for management of prairie streams faced with threats such as introduced species, intensive agriculture, grazing, and coalbed natural gas extraction. Although we developed this IBI based on data from Montana prairie streams only, our IBI can probably serve as a framework for other North American plains streams and our results suggest that the IBI approach may be useful in other semiarid regions of the world.

Fish diversity with relation to water quality of Bhadra River of Western Ghats (INDIA)

“…At BH site, a lot of physical barriers like big log inside the river site and fallen trees were noticed, and this could be the reason for low species richness. The same observations were made by Karr et al (1986), Arunachalam (2000), and Bramblett et al (2005).…”

A Fish-Based Index of Biotic Integrity to Assess Intermittent Headwater Streams in Wisconsin, USA

“…This includes periods when the stream is intermittent, consisting of isolated pools with no surface flow between them, but not when the channel is completely dry or reduced to pools so small and shallow that fish survival in them is unrealistic. In such cases, application of the IBI should be deferred until the channel again contains sufficient water to support a fish assemblage (Bramblett et al, 2005).…”

“…However, most IBI's have been developed for larger warmwater streams, and headwaters have received little attention. This is a consequence of the general lower priority for environmental management of headwater streams coupled with the challenge of adapting the IBI to relatively depauperate and tolerant fish faunas (e.g., Bramblett and Fausch, 1991a;Lyons et al, 1995;Simon and Lyons, 1995;Bramblett et al, 2005). Indeed, IBI's designed for larger streams may consistently mischaracterize and undervalue headwater streams (e.g., Wiley et al, 2003).…”

The Stream Biome Gradient Concept: factors controlling lotic systems across broad biogeographic scales

“…These stressors occur across all biomes, but anthropogenic disturbances could have greater influence in arid and semi-arid regions because animals are already near their physiochemical extremes (Bramblett et al 2005). Alternatively, some biomes are more prone to disturbance.…”