I recently came across some published fishery studies going back to the 1950s that I found rather interesting. As an example, I've snipped some excerpts out of one that appeared in the Proceedings of the Oklahoma Academy of Science for 1955. In this case, a 184-acre Oklahoma lake that was filled with overabundant and stunted crappie. Now days, we'd likely manage that lake by promoting harvest via some form of media outlet, possibly removing any applicable size or bag limits, or some other type temporary regulation. Back then they simply 'nuked' it. I also liked their somewhat "plain language" conclusion.
Expansion of the Crappie Population in Ardmore City Lake Following a Drastic Reduction in Numbers
Robert M Jenkins
- "One of the fishery management tools currently employed in Oklahoma involves the elimination of 50 to 95 percent of the fish in a lake where the populations of desirable species are determined to be slow-growing and overcrowded. The desired result is the creation of conditions conducive to greatly accelerated growth, a phenomenon which is associated with excellent fishing success."
- "An attempt to drastically reduce the numbers of stunted fishes in Ardmore City Lake, particularly white crappie and black crappie, was made in September, 1953. The application of 2550 pounds of powdered rotenone to about 80 percent of the lake surface killed large numbers of gizzard shad, crappies, and carp. Largemouth bass, channel catfish, yellow perch, and various sunfishes were killed in lesser numbers. In order to evaluate the effects of the reduction in population on reproduction and growth, sampling with wire traps was carried on at intervals during the following two years."
- "The production of large numbers of crappie by a very limited number of adults was one of the more striking results of the investigation."
- "The estimate of the population existing following rotenone treatment in 1953 is 27 black crappie, 18 of which were over 8 inches in length the following spring, and 23 white crappie, 10 of which exceeded 8 inches. None of the fish exceeded 11 inches, and all were 4 to 6 years of age."
CONCLUSION
- "An estimation of the crappie population in Ardmore City Lake revealed that a population of 5O adults with a reproduction potential of about 590,000 produced a population which at one year old numbered 200,500 fish. The study demonstrates the fecundity of these two species, and emphatically underlines the insanity of stocking crappie in lakes where they are already present."
A little surprising since I have seen ZERO dead crappie following the limited kills at Lake Waveland. I had assumed that they were not as susceptible as some species to low concentration rotenone
Posted by: Steve Woodrow | March 03, 2015 at 03:33 PM