Cue the theme music. . . .
It has been almost three years ago that I went into some detail about the fisheries renovation that was done on the west lake at our Mormon Island State Recreation Area,( http://www.outdoornebraska.ne.gov/parks/guides/parksearch/showpark.asp?Area_No=123 ), http://magazine.outdoornebraska.gov/2010/08/rotenone-renovation/ . What I want to share with you here is a paper that documents the fisheries science behind a rotenone renovation, http://digitalcommons.unl.edu/tnas/418/ . If you wish you can download the entire paper, http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1344&context=tnas .
A rotenone renovation is just one tool that fisheries managers can use in order to produce and maintain healthy fisheries that provide good fishing. When a fishery is scheduled for a rotenone renovation folks often worry that we are going to sacrifice a bunch of nice fish. As this paper points out, if there were a bunch of nice fish still present, we would not be doing the rotenone renovation in the first place. The fish community of Mormon Island West, at the time of the rotenone renovation was dominated by common carp and gizzard shad. Those two species represented over 90% of the total fish biomass of that lake. Species like largemouth bass and bluegill represented less than 5% of the entire biomass of fish in that pit at the time of the rotenone renovation.
For some perspective, counting and weighing of dead fish following the rotenone renovation of Mormon Island West provided an estimate of 876.6 total pounds of all fish per acre of that sandpit. Nebraska waters, even sandpits are very productive, and if they are not dominated by unwanted species of fish can produce tremendous fishing opportunities.
The rotenone renovation of Mormon Island West occurred three years ago this summer. Largemouth bass, bluegill, black crappie, channel catfish and muskellunge have been stocked back in the pit since that time. It may take awhile for some of those fish to grow to large, trophy size yet, but following rotenone renovations the growth of fish is almost always exceptional and for sure some of those would be large enough to catch by now. It is time to start fishing there again!