In urban areas, increases in impervious surfaces result in dramatic changes to the hydrology of streams. These changes in hydrology lead to drastic effects on the geomorphology and biotic community of streams. Efforts are underway to restore the biological integrity of headwater streams through the implementation of green infrastructure and provide more natural hydrology. However, it is often unclear whether this infrastructure results in the intended biological improvements and what factors might impact recovery. Our project assessed the fish community and movement patterns of fish prior to installation of stormwater infrastructure in Cooper Creek, a headwater urban watershed in Cincinnati, Ohio. Our goal was to characterize fish community composition prior to stormwater management and assess how fish movement is affected by extreme hydrology. We performed electrofishing surveys of the fish community in fall 2018 in six approximately 150-200m stream reaches. In early winter 2018, we individually tagged fish to track their movements. We captured fish using seines and minnow traps and implanted >100 Creek Chub with passive integrated transponder (PIT) tags. We used regular surveys with a portable PIT tag antenna in a 500 m stream reach to track fish movements during spring and summer 2019.
Results/Conclusions
Our fall 2018 fish surveys revealed a relatively simple fish community composed of Creek Chub (Semotilus atromaculatus), Central Stoneroller (Campostoma anomalum), Western Blacknose Dace (Rhinichthys obtusus), Green Sunfish (Lepomis cyanellus), White Sucker (Catostomus commersonii), and Bluntnose Minnow (Pimephales notatus). Upstream reaches were primarily composed of Creek Chub and Central Stonerollers, while downstream sites had more diversity including Western Blacknose Dace, Green Sunfish, White Sucker, and Bluntnose Minnow. We found Creek Chubs dominated the most upstream reach, while downstream reaches were more evenly distributed with Central Stonerollers, and Bluntnose Minnows, and occasional occurrence of other taxa. Our tagging efforts were concentrated on the culvert outlet which forms the headwater of Cooper Creek, where Creek Chub were the dominant species. Of the 100 fish initially tagged in the culvert outlet, we physically recaptured 14 in the culvert after several storm events. This shows that these fish are either able to withstand high flows or recolonize the culvert habitat following storm events. Our data provide baseline fish community composition and movement patterns that will help inform whether the planned stormwater infrastructure actually leads to improvement of the fish community in this urban headwater stream.