A diel and seasonal study of a freshwater stream fish community
A diel and seasonal study of a freshwater creek community was done on the Catskill Creek, Greene County, New York. Data were obtained using SCUBA to observe the fish. The objective was to determine whether day/night and seasonal patterns of fish activity and distribution indicate trophic and spatial resource partitioning. The time and light correlates of twilight activities of four diurnal and nine nocturnal species were studied (diurnal species: Micropterus dolomieui, Lepomis macrochirus, Notropis cornutus and Semotilus atromaculatus; nocturnal species: Anguilla rostrata, Ictalurus nebulosus, Catostomus commersoni, Salmo trutta, Salvelinus fontinalis, Oncorhynchus mykiss, Ambloplites rupestris, Micropterus salmoides and Pomoxis nigromaculatus). The study site was divided into 3 sections characterized by a particular type of bottom substrate, structural shelters present and current. Each section was then studied to determine the type of fish using it. As the temperature of the water fell, nocturnal and crepuscular species switched their activities primarily to the daytime. As the water continued to cool, fish species gradually disappeared until only the trout were active in the stream. Suckers and bluegill sunfish were found buried under rocks and debris in the creek bottom. It was not determined where the other fish species went as water temperature fell. As the water warmed in the spring, the different fish species again appeared, until by summer all species again were present. The twilight activities of the fish community in the creek were similar to those of coral reef fishes (i.e., an increase in several non-feeding behaviors, a shift from group to individual activities and an increase of predator activity during twilight). A new behavior was discovered during the study and was investigated in depth. It was a feeding association between the smallmouth bass and the white sucker with the smallmouth bass feeding on organisms chased into the water column by the bottom feeding sucker.
Kirker, Richard Joseph, "A diel and seasonal study of a freshwater stream fish community" (1989). ETD Collection for Fordham University. AAI8918637.