Journal of the Southeastern Association of Fish and Wildlife Agencies

Four experiments with 0.1 p.p.m. or less of 5 percent emulsified rotenone were conducted at Lake Beulah, Florida. Lake Beulah, an eighteen-acre lake with an average depth of 14.9 feet characteristically had a heavy plankton production. Estimated pounds of gizzard shad killed progressively declined during the four experiments although concentrations of rotenone were increased. The first kill was estimated at 23,455 pounds of shad; second kill, 7,976 pounds; third kill, 1,528 pounds; and fourth kill, 1,060 pounds. Small numbers of fish of other species were also killed. Length-frequency studies of gizzard shad indicated an over populated condition existed at the time of the first poisoning. Thereafter reproduction and rapid growth of this species occurred. Evidence exists that threadfin shad may have been eliminated from Lake Beulah following the use of the selective poisoning technique. Total kill calculations included results from bottom sample screens.

Preliminary Investigations Of Chemical Soil And Water Relationships And Lime Treatment Of Soft Water In Georgia Farm Ponds 0 By H. D. Zltllltr And A. B. Mon'l'go:mltry Georgia Game And Fish Commission Atlanta, Georgia Abstract A general classification of pond waters according to hydrogen ion and total hardness of calcium and magnesium is correlated with the major soil regions in the state. Specific correlation between Piedmont soils and Coastal Plain soils are apparent. Limited data is available on lime treatment of soft waters and relationships to fertilization programs. Pond bottom soil analysis before and after liming exhibit beneficial nutrient releases following treatment, and water concentrations of calcium and magnesium and hydrogen ion are presented before and after lime treatment. The efficiency of fertilization programs have been improved following lime treatment and amounts of fertilizer required for optimum results reduced.

The technique of operation of the haul seine as traditionally used in the large fresh water bodies of Florida is discussed. Limiting factors inherent in the sampling device are enumerated and illustrated by seine catches from several lakes. Rotenone studies from some of these lakes are contrasted with the seine catches. The results of creel census studies in lakes extensively fished by sportsmen, by reflecting proportionate quantities of game fishes similar to quantities taken in the haul seine, are quoted as further validation for its use in qualitative population. sampling. Difficulties in quantitative sampling by this method are discussed. It is shown to be of questionable value when employed for approaching absolute terms such as productivity in pounds per acre except in certain special cases. The value of the haul seine for purely relative comparisons is emphasized.

To facilitate the evaluation and use of population studies, reports should include: 1. A description of the area sampled, including the chemical classification and physical type of water, the type of bottom, depth of water, speed of movement and other information necessary to describe the environment from which the population came. 2. A description of the method of sampling employed in sufficient detail to enable the results to be evaluated and compared with results of other surveys. 3. Methods of measuring the results should be stated. The report should state if an attempt was made to recover fishes of all sizes, and if all fish were weighed or partly weighed and partly estimated. Such information is necessary for evaluation of the reliability of the results. 4. The population composition should be listed by species, with the numbers and weights of fish in each inch-group.

A simple method for the comparative testing of herbicides for emergent weeds was developed and used over a three-year period to compare the effect of recently introduced herbicides with that obtained from the use of a 2,4-D ester in a fuel oil carrier. The herbicides tested included amitrol (3-amino-l, 2, 4-triazol), dalapon (sodium salt of 2, 2 dichloropropionic acid), erbon (2- (2, 4, 5 tricholorophenoxy) ethyl 2,2 dichloropropionate), Kuron (propylene glycol butyl ether ester of 2-(2,4,5 trichlorophenoxy) propionic acid), Kuramine (amine formulation of 2-(2,4,5 trichlorophenoxy) propionic acid), CMU (3-(p-chlorophenyl) -1, 1-dimethylurea) and the propylene glycol butyl ether ester of 2,4-D. These compounds were tested singly and in various combinations of two herbicides. TCA (sodium salt of trichloroacetate) was combined with several of the forms also.

From November, 1955, through May, 1956, trammel and riprap nets of 3-, 3.5- and 4-inch bar mesh and gill nets of 3- and 4-inch bar mesh were fished by resident commercial fishermen under the supervision of State Fisheries Biologists, in T. V. A. lakes of Alabama. A total of 10,425 fish which weighed 42,689 pounds was caught, of which 95.4 percent was rough fish. All of the nets were selective in taking rough fish. Whip set trammel nets were the most effective type of net fished, followed by fixed trammel, riprap anc~ gill nets. In general, as the mesh size increased from 3 to 4 inches, the effectiveness of all nets decreased.

Ponds stocked April 30 with 80 Tilapia mossambica per acre and drained October 16 produced in the 170-day experiment 1,480.9 pounds tilapia per acre in a fertilized pond and 3,224 pounds per acre where feeding was added. Tilapia (1- to 2-inch) stocked into ponds June 13 reached 5 to 8 inches in size in 126 days. A 2.6-acre pond was stocked April 18-20 with 80 brood tilapia per acre. The pond was fertilized and the fish fed. Tilapia hatching in this pond grew large enough to provide fishing by August 1. In the first 2-week period of fishing, the catch per acre was 1,222 fish weighing 226 pounds. These fish feed upon plankton and filamentous algae and may be of value in ponds for the control of the latter.

Perhaps the most universal problem in many of Kentucky's streams, from the angler's viewpoint, is that of excessive numbers of rough fish in proportion to the numbers of game fish. This paper presents the findings of a Dingell-Johnson project that has been concerned since 1952 with the manipulation of populations in 3 streams typical of types found in the state. The upper 46 miles of North Fork River in Mason County and 12 miles of Whippoorwill Creek in Logan County were treated with 5-percent powdered rotenone in 1952 to eradicate their entire fish populations. Both streams were immediately restocked with game and panfish species. Annual sampling of the population of both streams revealed a gradual reversion to the original population composition in each stream.