Journal of the Southeastern Association of Fish and Wildlife Agencies

The fall-winter foods of otters living along the coast are largely fishprincipally carp, catfish, suckers, and sunfish. The otters' diet at other seasons of the year is largely comprised of fish, blue crab, and crayfish. Other foods, all taken in small quantities, are shrimp, clam, water beetles, decapod, muskrat, rails, and waterfowl. An examination of 53 female otters from northeastern counties over a 12winter period (1947-48-1958-59) showed that breeding starts during January and continues into February and possibly into March. Of eight gravid otters in a study sample of 53, five contained three embryos, two contained two, and one contained four embryos. This is an average of 2.88 embryos per female. Sex data obtained on 273 otters showed 149 (55%) males and 124 (45%) females. This is 120 males for every 100 females. Weights were obtained on a total of 238 otters.

Length and weight data were gathered during a short time-period on several species of fish from a large lake and a connecting marsh canal. The marsh had recently gone dry, forcing the fish to crowd into the canal. Analysis of covariance was used to compare the length-weight relationship of largemouth black bass (Micropterus salmoides) , redear sunfish (Lepomis microlophus) and bluegill (Lepomis macrochirus) from both habitat types. The bass from the canal were found to be significantly heavier for their length than those from the lake. Various possible explanations for this phenomenon are discussed. The author's conclusion is that the most logical explanation for the phenomenon is increased feeding by the bass under these crowded conditions. No detectable difference was found in the length-weight relationship of redear sunfish and bluegill from the two habitats. No chain pickerel (Esox niger) were captured in the lake but several hundred were taken in the canal.

Laboratory experiments were conducted to determine the toxicity of Noxfish (an emulsifiable formulation containing 5 percent rotenone) and Pro-Noxfish (an emulsifiable formulation containing 2.5 percent rotenone plus 2.5 percent Sulfoxide as a synergist) to eggs of common carp (CyprinMs carpio) and fathead minnows (Pimephales promelas). Spawning devices were added to brood ponds and examined daily to obtain eggs of known age for testing. The 325 carp eggs were 24 to 48 hours old when treated. Ninety percent of the carp eggs in control containers hatched. The LD.o's obtained for carp eggs at approximately 75° F. were: Noxfish, 0.091 p.p.m., Pro-Noxfish, 0.178 p.p.m. Fathead minnow eggs less than 31 hours old or 101 to 120 hours old were equally susceptible to the poisons. Ninety percent of the fathead minnow eggs in control containers hatched. The LD50's obtained for fathead minnow eggs at 70° to 76° F. were: Noxfish, 0.142 p.p.m.; Pro-Noxfish, 0.233 p.p.m.

The channel catfish (Ictalurus punctatus) has proved to be a very promising sport fish in ponds. Fingerlings stocked in February 1958 in a 12.4-acre pond at the rate of 2,000 per acre in combination with fathead minnows and largemouth bass, and given supplemental feeding daily except Sunday, averaged 0.7 pounds by September. During the following periods, September 24 to December 8, and March 14 to October 6, fishermen caught per acre 1,292.5 pounds of channel catfish, 36.9 pounds of largemouth bass, and 27.0 pounds of miscellaneous sunfish. The number of fishing trips per acre averaged 579 with a catch of 2.3 pounds per trip. Fishermen harvested 62 percent of the catfish stocked. The pond was drained November 17, 1959 and 180 channel catfish weighing 391.2 pounds, 51 largemouth bass weighing 34.5 pounds, 907 fatheads weighing 2.4 pounds, and 80.2 pounds of “wild” fish were recovered per acre.