Deve/opment and Application of an Index of Biotic ...

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Channel shiner was not listed separately by Haliwell et al. (1999) but was placed with the closely related mimic shiner in the intermediate category. * Rainbow ...
Deve/opment and Application of an Index of Biotic Integrity for Fish Communities of Wadeabie Monongahela River Tributaries William G. Kimmel and David G. Argent Biological and Environmental Sciences Department California University of Pennsylvania 250 University Avenue, Caiifornia, Pennsylvania 15419 E-mail: [email protected]

ABSTRACT We developed an index of biotic integrity (IBI) to assess the health offish communities inhabiting low-order tributaries of the Monongahela River in Pennsylvania. Environmental stressors observed were urbanization, agriculture, raw and treated sewage discharges, net alkaline mine drainage, and acid mine drainage (AMD). Species richness ranged from zero in streams impacted by AMD and/or untreated sewage to 24 in our reference stream. Our IBI classified the majority (>90%) of streams in this region as significantly stressed, receiving qualitative evaluations of "fair" to 'Veiy poor." Moreover, of the 4,090 fishes collected, only four species representing 2% of the total number collected were classified as intolerant to pollution. INTRODUCTION A variety of metrics have been developed to assess biological integrity in aquatic ecosystems, recognizing resident communities as sensitive to environmental perturbation (Barbour et al. 1999). Many have utilized benthic macroinvertebrate communities for the development of indices of diversity (Shannon 1949), community similarity (Krebs 1999), trophic structure, and pollution tolerance (Hilsenhoff 1982). Fish communities have received similar attention (Gammon 1980) leading to the evolution of integrated multimetric indices like those of Karr (1981) and Karr et al. (1986). Karr (1981) and Karr et al. (1986) created an index of biological integrity (IBI), to assess the health offish communities of midwestem warmwater streams, and the index was subsequentiy widely adapted and modified for regional and local (Fausch et al. 1984, McCormick et al. 2001, Smogor and Angermeier 1999) application throughout the U S and in several foreign countries (Kotze et al. 2004; Oberdorff et al. 2002). As a result, the original 12 metrics for fish communities now contain many alternative measures ^plicable to specific locales (Simon and Lyons 1995, Barbour et al. 1999). Based on "best professional judgment," local fish life histories, field and data validation, appropriate local and regional combinations of metrics are selected by biologists. Utilizing these metrics pennits comparison of ecologically stressed systems to a local reference condition. The Monongahela River basin in southwestern Pennsylvania historically suffered the insults of mining, sewage discharges, agriculture, and urbanization, and many tributaries as well as the mainstem are still impacted to varying degrees. In order to assess the condition of fish communities of the Monongahela River basin tributaries in Pennsylvania, we (1) developed a fish IBI for this particular system and (2) determined the efficacy of the IBI in assessing fish community healtii. METHODS AlsTO MATERIALS Description of the studv area The Monongahela River arises from the confluence of the West Fork River and Tygart River at Fairmont, West Virginia and flows 206 km north to Pittsburgh, Pennsylvania. Along its course, the Monongahela River traverses varying land uses mcluding active and abandoned coal mines, the industrialized Mid-Mon Valley, 183 Journal of Freshwater Ecology, Volume 21, Number 2 - June 2006

agricultural areas, forested patches, and small towns. Pollution from point and non-point sources has degraded water quality over much of the 5,252 km^ of the basin in Pennsylvania. Sampling design During the summers of 2003 and 2004, we surveyed 40 of the 51 named flowing tributaries of the Monongahela River in Pennsylvania (Kimmel and Argent 2005) using two-pass back-pack electrofishing (Heimbuch et al. 1997, Meador et al. 2003). Each sampling station began at the mouth and ended at a point 200-m upstream. If no fish were collected over the first 100-m during the first pass, sampling was terminated. Of the 40 streams, we eliminated 13 from consideration because they either contained barriers to fish passage prohibiting a survey of the appropriate length (100 or 200-m) or they were too large to effectively sample with back-pack electrofishing gear. The remaining streams (Table 1) were used to develop the IBI. Large specimens (>250 mm TL) and gamefish were identified in the field and released. All others were fixed in 10% formalin and identified in the laboratory. Visual observations were made of point sources of pollution and other cultural impainnents of each stream. We developed our IBI from these collections and fish distribution data found in Cooper (1983) and Argent et al. (1997) and validated the results using the split data method described by the U.S.EPA(1998). Table 1. Locations and dimensions of sampling stations on 27 wadeable Monongahela River tributaries. Northing and Easting are in decimal degrees. Length = m. Mean width = m. Area = m^. Stream Length Mean Width Area Northing Easting Muddy Ck. 200 8.3 1660 3955.745 7956.177 PikeR. 200 8.5 1706 4003.955 7953.969 Mingo Ck. 200 1584 4012.787 7957.723 7.9 Dunlap Ck. 200 7.3 1460 4001.233 7953.148 4000.764 7959.653 Fishpot R. 200 4.2 840 NeelR. 200 4.5 900 3957.019 7958.827 Whiteley Ck. 200 11.6 2320 3950.272 7956.310 Fallen Timber Ck. 3.4 688 4016.456 7953.042 200 Pigeon Ck. 2166 4011.961 7955.271 200 10.8 Little Redstone Ck. 200 5.4 1088 4006.096 7950.510 Sunfish R. 200 1.6 324 4011.862 7953.019 Maple Ck. 200 6 1200 4007.930 7953.483 Barneys R. 200 5.6 1128 4000.913 7958.991 Wallace R. 200 6.2 1240 3955.562 7956.802 RushR. 200 5.1 1020 4000.147 7955.827 200 5 1000 3953.483 7955.101 Middle R. 200 11.9 2380 4018.226 7952.929 Peters Ck. 200 2.2 436 4015.639 7954.697 Lobbs R. 1.4 272 4014.316 7956.591 Bunola R. 200 718 3957.678 7959.257 200 3.7 Bates R. 1360 4019.169 7953.922 Sandy Ck. 200 6.8 4.5 900 4023.095 7955.984 Streets R. 200 624 3959.728 7952.700 Meadow R. 200 3.1 690 4024.886 7954.946 Ninemile R. 100 6.9 3952.464 7955.072 8.7 874 Browns R. 100 3950.264 7954.662 608 CatsR. 100 6.1 498 3948.521 7954.871 Jacobs Ck. 100 5 184

RESULTS AND DISCUSSION Summary of fishes collected Among the 27 streams considered in the development of the IBI, we captured a total of 4,090 individuals representing nine families and 41 species or hybrids. Species richness ranged from 24 in Muddy Run to 0 in Jacobs Creek, Ninemile Run, Cats Run, and Browns Run, while Fishpot Run supported the highest density at 0.98 fish/m^ Median fish density for the 27 streams was 0.05fish/m^(Table 2). Of the total fish complement, only 2% were "intolerant" species, with the remainder nearly equally divided between "intermediate" (52%) and "tolerant" (46%). Table 2. Fish species richness and density among 27 wadeable Monongahela River trihiitnripe

Stream Muddy Ck. PikeR. Mingo Ck. Dunlap Ck. Fishpot R. Neel R. Whiteley Ck. Fallen Timber Ck. Pigeon Ck. Little Redstone Ck. SunfishR. Maple Ck. Barneys R. Wallace R.

FJoncifxr = XT^ K^UI.^^

Richness 24 24 21 17 14 14 14 13 13 11 10 10 7 7

Density 0.25 0.59 0.26 0.08 0.99 0.37 0.02 0.16 0.03 0.09 0.19 0.04 0.14 0.05

Stream RushR. Middle R. Peters Ck. Lobbs R. Bunola R. Bates R. Sandy Ck. Streets R. Meadow R. Ninemile R. Browns R. CatsR. Jacobs Ck.

Richness 7 6 6 5 4 3 3 1 1 0 0 0 0

Density 0.03 0.02 0.01 0.47 0.35 0.07 0.01 0 0 0 0 0 0

IBI develoDment From the 12 metrics of Karr et al. (1986) we selected 10 from those summarized in Barbour et al. (1999), which we felt best represented ambient conditions (Table 3). Species richness and density were weakly correlated with area sampled (r =0.50 and r =0.14, respectively) and thus were not considered in metric development. No significant relationship existed between species richness and stream order either; so scoring criteria were kept the same regardless of stream size. Metric #11 (% hybrids) and Metric #12 (% diseased individuals) were excluded because few hybrids (