Neotropical Freshwater Fishes

Today we began our work with Dr. Choudhury from St. Norbert College and his colleagues. They are interested in the freshwater fish species in the rivers draining into the Chagres River and the parasites that they carry. We started on the River Frijolito on Pipeline road and within less than 90 meters we caught hundreds of fish. With four hauls we were able to catch 7 species of Characidae (Tetras), 3 species of Poeciliidae (Guppies) and 3 species of neotropical catfish including an armored catfish, which are hard to find due to their cryptic coloration and bottom dwelling habitat.  The diversity of species in such a small area is amazing and when we first looked at the sample area it did not look like it contained the number of fish that we found.  This is yet another unique experience for us conducting field research in the tropics and it was a great hands on opportunity.  Wading through the cool water felt great compared to the heat of the forest.  After the fish were collected they were brought back to the lab where they were dissected for parasites.  This evening we were able to see a fluke that was taken out of the gut of one of the larger fish and nematodes from a catfish.  They were really neat to see up close and will be used to study the patterns of parasitism in neotropical freshwater fishes.  In a country surrounded by saltwater there is a whole world of neotropical freshwater fish to study and classify.