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