| |
Presented at the NABS Annual meeting, Pittsburgh, Pennsylvania, 2002
in Fish Ecology
FEEDING ECOLOGY OF LARVAL BLUE SUCKER (CYCLEPTUS ELONGATUS): A DIRECT BENEFIT OF RIVERINE BACKWATER INVERTEBRATES TO A MAIN CHANNEL FISH.
M.B. Flinn1, S.R. Adams2, and M.R. Whiles1. 1Department of Zoology, Southern Illinois University, Carbondale, IL, USA 62901, 2Department of Zoology, and Fisheries and Illinois Aquaculture Center, Southern Illinois University, Carbondale, IL, USA, 62901
Blue suckers (Cycleptus elongatus) primarily occupy swift currents in the main channel of large rivers within the Mississippi River basin, but the ecology of early life stages is not well documented. Over 230 larval blue suckers were captured by seining in backwaters of Pool 25 in the Upper Mississippi River in spring 2000 and 2001. We examined the diet of larval blue suckers (16-27mm total length) to document much needed life history information and to evaluate the importance of riverine backwaters as fish nursery habitat and areas of high invertebrate production. A total of 18 invertebrate taxa were identified in the fish guts with representatives from benthic (e.g., Chironomidae larvae, Oligochaeta), nektonic (e.g., Cladocera, Copepoda, Chaoboridae), and neustonic (e.g., Chironomidae adults, Bryozoa, Thripidae, Homoptera, Carabidae) habitats. Chironomidae (88%), Cyclopoida (77%), and Cladocera (50%) were found in the majority of fish examined. These groups accounted for 60%, 30%, and 5%, of the total gut content biomass, respectively. Feeding in backwaters by larval blue suckers demonstrates the importance of invertebrate communities in these habitats, even to a main channel fish, and is an example of the energetic link between riverine backwaters and the main channel.
|
|
