Fish sampling data from Navigation Pool 8 of the Upper Mississippi River, 1991 1997 Bartels, A. 2000. Fish sampling data from Navigation Pool 8 of the Upper Mississippi River, 1991 1997. U.S. Geological Survey, Upper Midwest Environmental Sciences Center, La Crosse, Wisconsin, April 2000. LTRMP 2000-S001. 105 pp. (NTIS #PB2000-105780) ABSTRACT Personnel of the Long Term Resource Monitoring Program for the Upper Mississippi River System have collected fish information in Navigation Pool 8 since 1989. In this report, I summarize data collected during the period 1991 97, in which gear deployment methods and sampling periods remained stable but fixed-site sampling changed to predominantly stratified random sampling in 1993. Sampling collections totaled 3,596 and yielded 324,948 fish of 91 species. Sampling effort increased over time, mainly when the change to random sampling occurred. Annual catches and species totals increased when random sampling was implemented; catches increased even with stable sampling effort in recent years. Of 12 gear types used, day and night electrofishing, seining, and mini-fyke netting were used the most often, produced the greatest catch totals, and also yielded the highest species totals each year. Bluegill (Lepomis macrochirus), spotfin shiner (Cyprinella spiloptera), and emerald shiner (Notropis atherinoides) were the most abundant species and also occurred in the greatest percentage of collections, indicating widespread abundance. Sixteen species yielded more than 5,000 individuals each. Family Cyprinidae was represented by 21 species and 141,497 fish, Centrarchidae by 9 species and 71,375 fish, and Catostomidae by 14 species and 26,776 fish. Twenty-one of 91 total species were rarely caught. Skipjack herring (Alosa chrysochloris), previously described as extirpated, was documented in the 1993 flood year. American brook lamprey (Lampetra appendix) and rainbow smelt (Osmerus mordax) were recorded for the first time in the Upper Mississippi River in 1993. Fantail darter (Etheostoma flabellare) and banded darter (Etheostoma zonale) were documented for the first time in Pool 8 in 1997. Population trends for 15 species of perceived interest to river managers and the public indicated mainly stable populations. KEYWORDS Fish community, fish monitoring, fishes, Long Term Resource Monitoring Program, Pool 8, Upper Mississippi River