Redear Sunfish Case Study

In this case study, scientists researched Lepomis microlophus (redear sunfish), Lepomis macrochirus (bluegill sunfish), and Microterpus salmoides (largemouth bass) that were collected from control ponds, natural lakes, and stormwater ponds in Orlando Florida. The fish were analyzed heavy metals such as zinc, lead, copper, cadmium, and nickel. The purpose of the study was to determine if the fish from the stormwater ponds had higher concentrations of these metals, and if there was a difference in the concentrations of the metals in each of the species (Campbell 1994). Stormwater ponds not only improve surface water quality and flood protection, they are also required in some stormwater management systems including central Florida. The St. …show more content…
The redear sunfish primarily feed on mollusks, found near the sediment, and has “shell crackers” or grinding teeth in back of the pharynx that are used to crush snails (Tomelleri and Eberle 1990). In Florida, they are also known to feed on scuds, prawns, and mayfly, dragon fly and midge larvae. When redear sunfish find snails on the bottom, they are known to take a vertical position and dive into the sediment head first (Wilber 1969). Largemouth bass are higher up in the food chain, sometimes the top predator in ponds; they feed on other fish, frogs, crawfish, frogs, and other wildlife in striking distance including mice and birds (Tomelleri and Eberle …show more content…
Four additional bodies of water were chosen as control ponds since they did not receive stormwater or urban runoff. In December 1991, January 1992, and March 1992, fish were collected using an electrofishing boat, gill net, and seines. Not all three species were available in most ponds and therefore a minimum of seven ponds were necessary. Five redear sunfish were taken from 3 ponds for a total of fifteen, as were both largemouth and bluegill from ponds they were found in. Five more fish from each species was taken from 3 control ponds. In all, 90 fish were collected, 45 from stormwater ponds, and 45 from control ponds. Fish small enough for birds to eat were desired, and each was measured (cm), tagged, and placed in plastic bags. The fish were frozen and taken to a lab for analysis. Also collected were composite sediment samples from each of the seven stormwater ponds and all four control ponds around the time that the fish were collected. These samples were cooled until taken for analysis (Campbell