Principe's Research Lab

I am primarily interested in the inter- and intra-specific competition among Centrarchids, especially black bass, in the local tributaries of southern Montgomery County, PA.  Nest builders like largemouth and smallmouth bass tend to be highly aggressive and territorial during the spawn, protecting their nest sites with ferocity.  A stream with limited flow and a lack of prime nest sites could put a burden on bass populations, thus reducing natural recruitment.  Furthermore, since most large Centrarchids are diurnal feeders preying on similar prey items, a small stream like Skippack Creek, would be expected to have limited food availability to support substantial growth.  One way to address these types of problems is through comparative examination of diet and growth.  Both of these factors can be easily collected without harming the fish.   For instance, upon capture, a length and weight of the fish is taken and the stomach contents collected by way of gastric lavage.  The fish is then fin-clipped and returned to the stream to continue its normal activities.  In this way, all recaptures can be later identified to assess growth through changes in length and weight over time.  Moreover, spawning nests can be mapped using technology such as GPS to determine the most often utilized nesting sites.  These data can then be translated into a spatial analysis using GIS software where critical space and food resources define a streams ability to maintain a diverse community of sunfish species.