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12 example, the abundance of a given fish species in a basin can be validly estimated using the MBSS design. Because first, second, and third order streams represent about 90% of the tidal and non-tidal stream miles in the Chester River basin, MBSS results should accurately represent overall stream quality in the basin. Examination of conditions in small streams also enables identification of specific problem areas where local protection, enhancement,and restoration efforts could be focused. To provide sorne cornparison of present and past conditions, historical information is presented where appropriate and available. In addition, information on land use, hydrology and other aspects of the basin are also represented so that observed conditions in streams can be placed in context.

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14 8 Chester River Basin: Environmental Assessment of Stream Conditions The lower part of the basin is dominated by stands of American beech, tulip poplar, red and white oak, hickory, VIrginia and loblolly pine. The upper portion is dominated by red maple, sweetlblack gum, swamp-white oak, swamp chestnut, southern red/pin/willow oak, green ash and sycamore. Because land in the Chester River basin is gently sloping and often near sea level, substantial areas are immersed during rainy periods. To make poorly drained areas suitable for agriculture, a large percentage of the streams in the basin were historically channelized. Today, many of the well drained areas are used for agriculture, while many poorly drained, more natural areas remain forested. Because of the chronic wetness of these bottomlands, trees are slow-growing and of limited commercial value. Conversely, these wet areas have high value as wildlife habitat (Batchelor 1996). The soils of the basin originate primarily from parent material of unconsolidated deposits of clays, silts, sands and gravels deposited as either coastal plain or alluvial delta (USDA 1982). Soils range from well drained to poorly drained. The climate in the basin is generally humid and mild, with an average annual temperature of55 F and an average daily maximum in the summer of 840 F at Chestertown, MD. The mean annual precipitation is 43 inches. Precipitation is evenly distributed throughout the year: monthly averages have ranged from 3 inches in February to 4 inches in June (Perez 1996). There is a total of 291 miles of first, second and third order non-tidal streams in the basin. First order streams make up 74% of the total non-tidal stream miles. while second and third order streams constitute 22% and 4% of the non-tidal stream miles. respectively. The three largest lakes in the basin are Urieville Lake (34 acres), Unicorn Lake (45 acres) and Wye Mills Community Lake (50 acres). All are publicly-owned and are classified as eutrophic (Fewlass 1983). LAND USE More than half (51 %) of the total acreage in the basin is used for agriculture, 21 % is classified as forest and another 21% is under water (Eastern Bay){Figures 1 and 2). Kent County, which lies between the Figure 1. Land use in the Chester River basin is predominantly agricultural. When considering only dry land, nearly 65% of the area is used for field crops or dairy operations (USDA 1982).

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29 and frequency of OCCUlTence for each American HI species of fish collected dwing MBSS sampling in Figure 12 shows the relative abundance of the six Ott..r' most abundant species in the basin. Consistent with the presence of only wannwater habitat Golden shiner in the Chester basin, Bluegill.Redftn pickerelfigure the sunfish famil y Relative abundance of the six most abundant fishspecies (Centrarchidae) had the in the Chester River basin (quantitative samples only),1995. greatest number of fi,sh Six species accounted for 750/. of the estimated totalabundance: species (eight), eastern mudminnow, 36%; golden shiner, 10%;tessellated followed by the darter, 10%; bluegill, 9%; redfin pickerel, 5% and American eel, 5 %. The eastern mudminnow was collected at the minnow family greatest number of sites (89%). (Cyprinidae) with seven species. The catfish family (Ictaluridae) was represented by six species, while the perch family (Percidae) was represented by three species. Various other families were represented by only one or two species. Eastern mud minnow basin-wide abundance of about 2,000 individuals. Only 2% of the chain pickerel were of leg a! size (14 inches or larger). Rare and Uncommon Species Gamefish Two species of gamefish, largemouth bass and chain pickerel, were collected in the Chester River basin. Largemouth bass were the most abundant gamefish collected, with an estimated density of almost 250 per stream mile. The estimated basin-wide abundance of largemouth bass was about 70,000 individuals, comprised primarily of young- of-year. Less than 1% of the largemouth bass collected were of legal size (12 inches or larger). The density of chain pickerel was estimated at nine per stream mile, with an estimated None of the species of fish collected during 1995 are listed as threatened, rare, or endangered by either Maryland or the U.S. Fish and Wildlife Service. However, the status of the swamp darter, Etheostoma fusiforme, is under review by the State of Maryland (Davidson 1996). Prior to this study, swamp darters had been found at only one Maryland site on the Western Shore. Otherwise, they were thought to be restricted to Maryland's lower Eastern Shore. A map of swamp darter distribution along with distributions of all other fish species taken in 1995 is shown in Appendix E.

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34 100 GI U C ~ = uu 0 ~ F"'8 ~ PIc--Frwg Species _L- C-~T- Figure 16. Percent occurrence of the five most commonly observ.ed amphibians ~nd rept~le~ for sampled streams In the Chester RIver basin In bull frog and pickerel frog were by far the most common species, occulting at 74%, 69% and 56% of the sites, respectively (Figure 16). Although the Eastern tiger salamander, Barking treefrog and Carpenter frog are rare, threatened or endangered species known to occur in the Chester River basin, none were found during the 1995 survey. SUMMARY OF STREAM RESOURCE CONnmONS Acid-related water quality in Chester River basin streams was generally good. Only a small percentage of streams were the streams very acidic. in the basin Most are of well buffered and few stream miles are chronically acidified. Sources of acidity in stream water can include acid rain and dissolved organic carbon from wetlands. The low gradient of streams and nutrient-rich runoff from agricultural lands likely work in concert to produce low dissolved oxygen levels in about one half of the stream miles in the basin. More than half the stream miles in the basin had degraded instream habitats. Destruction of vegetated riparian buffers, channelization, excessive siltation and groundwater withdrawal all likely contribute to these degraded conditions. COMMON SNAPPING TURTLE The common snapping tiirtle (Chelydra serpentina) was fo"nd at 1 " of the sites in the Chester River basin in This species is adive day and night dilring warmer months and prefer milddy-bottomed creeks and weedy shallows. The fish community sampled in the nontidal portion of the Chester River basin in 1995 was relatively diverse. Species richness was moderately high (37 species) and two species of gamefish were collected (largemouth bass and chain pickerel). However, die fish community was numerically dominated by pollutiontolerant eastern mudminnows. With the exception of the American eel, few migratory fish were present. However, there are 137 known barriers to migration

35 Chester River Basin: Environmental Assessment of Stream Conditions 29 -'--'-. ~-- - changed over time. The 1995 MBSS results establish a useful bench mark of cuitent fish species compositio~ distribution and abundance that can be used to track future changes. Figure 17. Barriers to fish migration in the Chester River basin. The most prevalent type of fish migration barrier is dams. With increased development in the basin, the number of pipe crossings and culverts will likely increase as more roads and sewerage systems are built. in the Chester River basin (Figure 17) which could restrict upstream movement of most species (Rhoades 1996). Most of the fish species in streams of the Chester River basin are relatively tolerant of pollution. Possible sources of such pollution include acid deposition, nutrient enrichment from agricultural and urban runoff, as well as the modification of physical habitat and water quality through logging and channelization. Three of the fish species taken in 1995 (bluegill, largemouth bass and green sunfish) are not native to the Chesapeake Bay drainage, although they are naturalized. Unfortunately, there is little historical information about fish communities in non-tidal streams of the Chester River basin, so it is difficult to determine how the distribution and abundance of these and other species have Based on the fish ml 62% of the stream miles in the basin were categorized as either good or fair. However, benthic macroinvertebrate community analyses suggesthat there are fewer good stream miles in the basin. Benthic community condition may reflect water quality impacts more so than large-scale habitat impacts that may be better reflected by fish communities. Further refinement of both fish and benthic macroinvertebrate indicators will enhance our ability to evaluate specific impacts to non-tidal streams. The amowlt of rain falling onto a stream's watershed may be an important factor in shaping the quality of the stream. Dry, low flow periods are often considered most stressful for stream life due to higher water temperatures, lower flows and less dilution of pollutants. Extremely heavy rainfall and high flows may result in large-scale changes in physical habitat and more downstream drift of aquatic animals. In 1995, total rainfall in the Chester River basin was about seven percent higher than average (Figure 18)(NOAA 1995). October and November were the wettest months, while March and July were among the driest months. Dry periods during the MBSS spring sampling period (March and April) and part of the summer sampling

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