Relative Abundance and Species Composition of Fish in Shadow Brook, Otsego County, New York

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1 7 VERTEBRATE MONITORING: Relative Abundance and Species Composition of Fish in Shadow Brook, Otsego County, New York Tom P. Bassista+ and John R. Foster* ABSTRACT During a fisheries survey of Shadow Brook (Otsego County, NY) in the summer of 994, 84 fish were captured representing 8 species and 8 families. This survey in combination with a 989 study, shows species of fish in Shadow Brook, compared to species found in a 970 survey. Increases in fish species appear to be due to introductions by fisherman. High levels of siltation appeared to be a key factor in a reduction in species occurrence from in 989 to in 994 at the Mill Street sample site. INTRODUCTION Recent studies have examined various attributes of Shadow Brook, such as nutrient levels (Fuller 987), algal growth (Merchant 987), macro-invertebrates (Zappala 989), and fecal bacteria (Coffin and Bicker 99). However, relatively little is known currently about the fish fauna of Shadow Brook. Previous studies of the fauna include a qualitative electrofishing survey conducted by the New York State DEC in 970, and a quantitative electrofishing survey conducted on one main stem site in 989 by Hayes (990). Thus, despite the fact that Shadow Brook has the largest drainage basin in the Otsego Lake watershed, an intensive study of the fish fauna present throughout its drainage basin has not been conducted to date. The relative abundance and species composition of fish provide good indicators of watershed degradation caused by land use, nutrient input, sediment load, or alteration of riparian vegetation. This study was conducted as part of a BFS research proj ect, sponsored by the U. S. Environmental Protection Agency and the NYSDEC, to characterize the fish fauna of the Otsego Lake watershed. Its purpose is to characterize the fish fauna of Shadow Brook, and its goal is to provide baseline data that will allow comparison of faunal changes for past and future studies. MATERIALS AND METHODS A fish survey was conducted at 7 sites in the Shadow Brook watershed during July and early August 994 (Figure ). Sites were visually assessed and sampled with landowner permission and if water was present. Sites I,,, 9, 0, II, and were too dry to hold fish and landowner permission was not secured to sample site-8. All other sites (0,, 4, 6, 7,, 4, IS, 6) were sampled. The mouth of Shadow Brook (Site-D) was sampled with a 0 foot haul seine and a foot, fine mesh shore seine. Main stem sites (, 4, and 6) and tributary sites (, 4, 6, 7) were sampled with a foot shore seine, fine mesh shore seine and a Smith Roote (Model-VII) backpack shocker. +Student in Fisheries and Aquaculture, SUNY College of Agriculture and Technology, Cobleskill, N.Y. 04 *994 SUNY Oneonta Biological Field Station Visiting Researcher

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3 TABLE Fish captured in the Shadow Brook watershed broken down by species and sample site. Family Scientific Name Common Name Mouth a Tributary sites 4 6 Main stem sites 4 6 Total Salmonidae Salvelinus fontinalis Oncorhynchus mykiss Brook Trout Rainbow Trout cupeidae Alosa pseudoharengus Alewife 7 7 Catostomidae Catostomus commersoni White Sucker Cyprinidae Clinostomus elongatus Redsided Dace Exoglossum maxillingua Cutlips Minnow Notemigonus crysoleucas Golden Shiner Notropis cornutus Common Shiner Phoxinus eos Redbelly Dace Pimephales notatus Bluntnose Minnow Pimephales promelas Fathead Minnow Notropis atherinoides Emerald Shiner Notropis hudsonius spottail Shiner Rhinichthys atratulus Blacknose Dace Semotilus atromaclatus Creek Chub Semotilus corporalis Fallfish Semotilus margarita Pearl Dace Esocidae Esox niger Chain Pickeral Ictaluridae Ictalurus nebulosus Ictalurus punctatus Brown Bullhead Channel Catfish 7 4 II Centrachidae Micropterus salmoides Micropterus dolomieui Lepomis gibbosus Lepomis macrochirus Lepomis auritus Ambloplites rupestris Largemouth Bass Smallmouth Bass Pumpkinseed Bluegill Redbreast Sunfish Rock Bass Percidae Etheostoma olmstedi Perca flavescens Tesselated Darter Yellow Perch 0 7 (,) <0

4 40 Main stem and tributary sample sites were blocked upstream and downstream with seines. Length, width, and average depth of the sample site was measured, as was the total time of electrofishing. Fish captured were anesthetized with MS-, identified, and measured for total length. New fish for the Otsego Lake watershed were preserved and placed in the reference collection at the BFS. All other fish were returned at the point of capture. Relative Abundance RESULTS A total of 84 fish were captured during this study, representing 8 species and 8 families (Table ). The family Cyprinidae (.%) dominated the fish fauna, followed by Catostomidae (.%), Centrachidae (.7%), Percidae (.%), Clupeidae (.%), Ictaluridae (.%), Salmonidae (.4%), and Esocidae (.%). White sucker (.0%), creek chub (9.%), and the blacknose dace (.8%) were the dominate species captured. All other fish species were found in moderate to extremely low numbers. Fish Distribution One hundred-forty eight fish representing species and 6 families were captured in the mouth of Shadow Brook (Table ). Many of the species (e.g. emerald shiner, spottail shiner) and families (e.g. Esocidae and Clupeidae) that were found only at the mouth are more typical of the lake ecosystem instead of a small stream. Further, Centrachids represented by six species (largemouth bass, smallmouth bass, pumpkinseed, bluegill, redbreast sunfish and rock bass), composed % of the total fish found at the mouth of shadow brook. These species are typical of the littoral zone of Otsego Lake. The four sites (, 4,, and 6) sampled on the main stem of Shadow Brook contained the largest number of fish (78), species (9), and families (6). Cyprinids made up.4% of the total population of fish in the main stem. Catostomidae with a single representative species, white sucker, made up 8.4% of the total population. Warmwater Centrachids were noted at every site and made up.6% of the total population.

5 4 Table Relative Abundance (%) of Fish Captured at the Mouth, Main Stem, and Tributaries of Shadow Brook in 994. Family Species Mouth Main Stem Tributaries Salmonidae Brook Trout Rainbow Trout..8 Cupeidae Alewife 8. Catostomidae White Sucker Cyprinidae Blacknose Dace Creek Chub Fallfish Redbelly Dace Bluntnose Minnow Pearl Dace Common Shiner Cutlips Minnow Golden Shiner Fathead Minnow Emerald Shiner Spottail Shiner Redsided Dace Esocidae Chain Pickeral.4 Ictaluridae Brown Bullhead Channel Catfish.7.9 Centrachidae Largemouth Bass Smallmouth Bass pumpkinseed Bluegill Redbreast Sunfish Rock Bass Percidae Tesselated Darter Yellow Perch Most tributary sites were dry (,,, 9, 0,, and ) or otherwise did not contain fish (site-7). The three tributary sites (sites, 4, 6) containing fish had relatively little flowing water, and fish were confined to pools. Consequently, the smallest number (8) of fish were captured in the tributaries of Shadow Brook (Table ). Further, the fish fauna was least diverse in the tributaries representing six species in four families. Blacknose dace was the dominant species, particularly at site-6. All other species captured were in extremely small numbers. Fish Faunal Changes Over the past 4 years there has been a substantial increase in the number of fish species found in Shadow Brook (Table ). Only species were found in the 970 survey conducted by DEC, while species have been found in surveys conducted by the BFS in 989 and 994. A comparison of the fish captured at site-6 in 989 (Hayes) and this study, indicates that at least some sites have had a decrease in species present

6 4 in recent years (Table ). In 989 the cobble-pebble substrate at the poolriffle sample site (6) had a dusting of silt, and the fish fauna was indicative of clean clear streams (Table ). However, in 994 site-6 was turbid and covered with a thick layer of silt. The number of fish species present fell from in 989 to in 994. Margined madtom, longnose dace, Atlantic salmon, and brown trout, that were captured at site-6 in 989 were not captured in the entire Shadow Brook watershed in 994. DISCUSSION Watershed degradation may directly impact the fisheries ecology of Shadow Brook as well as indirectly impacting the fisheries ecology of Otsego Lake (Groff et al. 99). Fish provide a good measure of aquatic habitat integrity (Karr 98), because they () occur in all but the most polluted aquatic ecosystems, () are relatively numerous, () are easy to identify, and (4) typically occur with representative species fulfilling a variety of niches and trophic levels. Aquatic habitat degradation is apparent in Shadow Brook. Compared to other streams in the Otsego Lake watershed, Shadow Brook has the warmest water temperature (Hayes 989), lowest dissolved oxygen concentrations (Hayes 989), highest nutrient levels (Fuller 987), and greatest sediment load (Fuller 987). Habitat degradation appears to be directly related to the fact that a large percentage of Shadow Brook's watershed is surrounded by agricultural land and only.% of the stream's riparian zone is forested (Fuller 987). Salmonid fishes, which require riparian vegetation for cover and to maintain cold, clean waters, were a minor component of the Shadow Brook fish fauna. Even in the tributary streams, riparian vegetation was limited (Figure ). Water temperatures, depths, and flows apparently were not maintained at a level that would support substantial populations of salmonids or other species. In fact, significant portions of the Shadow Brook watershed were too dry to hold fish in the summer. Sites that were classified as dry in this study may be capable of holding fish at other times of the year or during wet summers. The occurrence of salmonid fishes and other species of clean, well oxygenated waters is apparently decreasing. For example, brook trout, brown trout, and rainbow trout were angled from Site-, and Atlantic salmon were captured in site-6 in the summer of 989 (Hayes 989). In this study, seining and electrofishing conducted in the same pools indicated that these species were absent. Further, species indicative of good water quality that were present in 989 were absent (margined madtom and longnose dace) or rare (fallfish). Habitat degradation was particularly apparent at site-6 where turbidity and siltation were high, and fish fauna dropped from species to species between 989 and 994. In 989 site-6 had the lowest density of fish of the Otsego Lake tributary streams (Hayes 989), and fish densities in 994 appeared even lower. Unfortunately, at the request of Region-4 NYDEC depletion sampling was not carried out, thus changes in density could be quantified. The increase in the number of species present in the Shadow Brook watershed from in 970 to in the surveys may be indicative of eutrophication. Species captured for the first time in the Otsego Lake watershed (MacWatters 98) include; fathead minnow, pearl dace, rainbow trout, and channel catfish. Species caught only once before include the cutlips minnow and redbelly dace noted by Hayes (989) and Hayes and Foster (989), and the redside dace noted by Brooking (99). The alewife, another introduced species (Foster 989), had not previously been captured in streams in the Otsego Lake watershed. Fisherman dumping their bait buckets probably account for the introduction of the minnow species. The introductions of alewives, channel catfish, and rainbow trout were probably deliberate attempts at improving fishing. The fish fauna of Shadow Brook has been significantly impacted by species introduction and habitat degradation. Fish that require cold, clean silt-free

7 Table Shadow Brook fish fauna during past DEC (970) and Biological Field station surveys (989 & 994). 4 stream Survey Site-6 Survey Family Species Salmonidae Brook Trout Rainbow Trout ++++ Brown Trout 989 Atlantic Salmon cupeidae Alewife ++++ Catostomidae White Sucker Cyprinidae Blacknose Dace Creek Chub Redbelly Dace ++++ Bluntnose Minnow Pearl Dace ++++ Common Shiner Cutlips Minnow Golden Shiner ++++ Fathead Minnow Emerald Shiner ++++ Spottail Shiner ++++ Redsided Dace ++++ Fallfish Longnose Dace Esocidae chain Pickeral ++++ Ictaluridae Brown Bullhead ++++ Channel Catfish ++++ Margined Madtom Centrachidae Largemouth Bass ++++ Smallmouth Bass Pumpkinseed ++++ Bluegill ++++ Redbreast Sunfish ++++ Rock Bass Percidae Tesselated Darter Yellow Perch

8 waters, such as salmon, trout, and cutlips minnows (Smith, et al. 97) are a minor and decreasing component of the fish fauna. At this time the fish fauna of Shadow Brook is dominated by generalists (fathead minnow), coolwater (suckers), and warmwater (sunfish and catfish) species that can tolerate degraded water quality. 44 ACKNOWLEDGMENTS Dylan Sickles, James P. Hakala, Steven Foster, and Shawn Hayes assisted In the collection of field data. LITERATURE CITED Coffin S. and K. Bicker. 99. Fecal bacteria analysis of Otsego Lake and its tributaries. In th Ann. Rept. SUNY Oneonta Bio. Fld. Sta., SUNY Oneonta. pp. 0-. Fuller, R. L A study of nutrient loading/limitation in the four main tributaries to Otsego Lake. In 0th Ann. Rept. SUNY Oneonta Bio. Fld. Sta., SUNY Oneonta. pp Groff, A., J. Homburger and W. N. Harman. 99. Otsego Lake Limnological Monitoring. In th Ann. Rept. SUNY Oneonta Bio. Fld. Sta., SUNY Oneonta. Harman W. N., L. P. Sohacki, and M. Albright. 99. United States Environmental Protection Agency Sponsored Phase I Diagnostic/Feasibility Study-Otsego Lake Watershed. In th Ann. Rept. SUNY Oneonta Bio. Fld. Sta., SUNY Oneonta. pp. 8. Harman W. N. and L. P. Sohacki List of fishes present in Otsego Lake or streams tributary to the lake: Table 4. In Occasional Paper No. November 977. SUNY Oneonta Bio. Fld. Sta., SUNY Oneonta. pp. 0. Hayes, S. A Preliminary fish survey of the Otsego Lake watershed. In th Ann. Rept. SUNY Oneonta Bio. Fld. Sta., SUNY Oneonta. pp Karr, J. R. 98. Assessment of Biotic Integrity Using Fish Communities. Fisheries (Bethesda) 6 (6) :-7. Macwatters, R. C. 98. The Fishes of Otsego Lake (nd Edition) Occ. paper #, SUNY Oneonta Bio. Fld. Sta., SUNY Oneonta. Merchant, M A time series study on nutrient limitations in three tributaries to Otsego Lake. In 0th Ann. Rept. SUNY Oneonta Bio. Fld. Sta., SUNY Oneonta. pp Scott, W. B. & E. J. Crossman. 97. Freshwater fishes of Canada. Bull. Fish. Res. Bd. Can. 84: 966 pp. Smith, C. L. 98. The inland fishes of New York State. Dept. of Envir. Cons. Albany, NY. pp. Zappala K A macrobenthic survey of four major tributaries to Otsego Lake. In 0th Ann Rept. SUNY Oneonta Bio. Fld Sta., SUNY Oneonta. pp. 8-0.