Benthic organisms are remarkably diverse and vary with habitat. They include protozoa (like amoebas), sponges, cnidarians, flatworms, nematodes, isopods, crayfish, amphipods, mollusks, gastropods, leaches and aquatic worms, pelecypods, insects, and fish. Benthic species I have observed in my area (Cobb County, Georgia) include the Asian Clam (Corbicula fluminea), larval brook salamanders (Eurycea sp.), common sunfishes (Lepomis sp.), the Chattahoochee Crayfish (Cambarus howardi), caddisfly larva (Order Trichoptera), damselflies and dragonflies larval (Order Megaloptera), mayfly larva (Order Ephemeroptera), dragonflies and damselfly larval (Order Odonata), aquatic worms (phylum Annelida), Eastern Dobsonfly larval (Corydalus cornutus), water snakes (Nerodia sp.), longjaw minnow (Ericymba amplamala), river Cooter (Pseudemys concinna), true bugs (Order Hemiptera), true flies larval (Order Diptera), beetles (Order Coleoptera) and stonefly larval (Order Plecoptera). It is worth noting some of these species may only occupy the benthos for a period.
Image of a Brook Salamander. Brook salamanders are a genus, Eurycea, image by Lauren Schramm
In some streams, Asian clams, an invasive aquatic species, can be one of the largest components of the benthic invertebrate community (Poff et al.,1993), however this is not the case in all streams in Cobb County. Black et al. (2003) evaluated benthic macroinvertebrate populations of two local streams: Sope Creek and Rottenwood Creek. In Sope Creek they found Ephemeroptera and Diptera to be the dominant orders. In Rottenwood Creek they found Trichoptera and Diptera to be the dominant orders.
An Asian Clam (Corbicula fluminea). Image by Lauren Schramm.Continue reading