. Bulletin. Natural history; Natural history. 372 Natural History Survey Bulletin Vol. 27, Art. 5 BLUE GILL LAUDERDALE (F)- HOOKER (F) A PHELPS (F) WELLS •• BOAZ — ELAM X. 1947 1948 1949 1950 1951 1952 Fig. 10.—Number of bluegills kept per man-hour of angling in fertilized (F) and unfer- tilized ponds; data from table 20. sized bluejj;ills was smaller in Lauderdale than in Phelps or Hooker, table 24. I'hree factors may have been favorable to the growth of fish in Lauderdale for 1 or 2 years at the beginning of the study but not during the last 4 years. (1) Be- fore t
. Bulletin. Natural history; Natural history. 372 Natural History Survey Bulletin Vol. 27, Art. 5 BLUE GILL LAUDERDALE (F)- HOOKER (F) A PHELPS (F) WELLS •• BOAZ — ELAM X. 1947 1948 1949 1950 1951 1952 Fig. 10.—Number of bluegills kept per man-hour of angling in fertilized (F) and unfer- tilized ponds; data from table 20. sized bluejj;ills was smaller in Lauderdale than in Phelps or Hooker, table 24. I'hree factors may have been favorable to the growth of fish in Lauderdale for 1 or 2 years at the beginning of the study but not during the last 4 years. (1) Be- fore the stocking of the ponds for the ex- periment reported here, fish-food organ- isms—invertebrates as well as larval am- phibians—had a longer time to build up their populations in Lauderdale than in Hooker or Phelps. In 1946 Lauderdale was without fish for 6 months prior to stocking (May to November), Hooker and Phelps for onlv 2 months (September to November). Brown & Ball (1943: 267) showed that certain fish-food organ- isms as well as fish were destroyed by the rotenone treatment of Third Sister Lake, Michigan. Ball Si Hayne (1952: 44—5) showed evidence of an expansion in fish-food organisms in a lake after all fish had been removed. (2) In November, 1946, Lauderdale was given a slightly heavier stocking in terms of fish per acre than the other ponds; this heavier stock- ing might account for the better bass fishing in 1947. Presumably the initial advantage in numbers would have ceased to be a factor in 1948 or 1949, when the offsprinir of the fish used in stocking the pond reached harvestable size. (3) Lauder- dale had been dosed with fertilizer in 1945. As a result of an error in the reported area of the pond, Lauderdale received more fertilizer in terms of pounds per acre at full stage than either Hooker or Phelps. However, water levels in mid- summer were always much lower in Phelps than in Lauderdale, so that Phelps. Please note that these images are ex
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