. Bulletin. Natural history; Natural history. July, 1966 Hansen: Stocking and Sport Fishing at Lake Glendale 119 while marking is in progress. The pop- ulation at any one sampling time is 1 , , r , ^ (AB) computed by the tonnula ^,' . , in which A is the total number of fish in the sample, B is the number of marked fish in the entire population when the sample is taken, and C is the number of marked fish in the sample. The last in each series of population estimates (for example, the estimates based on Sample 9, Table 3, and Sample 11, Table 4) is assumed to be the most nearly accurate in the
. Bulletin. Natural history; Natural history. July, 1966 Hansen: Stocking and Sport Fishing at Lake Glendale 119 while marking is in progress. The pop- ulation at any one sampling time is 1 , , r , ^ (AB) computed by the tonnula ^,' . , in which A is the total number of fish in the sample, B is the number of marked fish in the entire population when the sample is taken, and C is the number of marked fish in the sample. The last in each series of population estimates (for example, the estimates based on Sample 9, Table 3, and Sample 11, Table 4) is assumed to be the most nearly accurate in the series. The samples used in the mark-and- recovery estimate were obtained with an electric shocker carried in a boat (Fig. 5); the current was furnished by a 115-volt, 11-ampere generator. Sam- ples were obtained in several runs, each covering about one-sixth to one-half of the 1,300-foot section of channel. All parts of this 1,300-foot section were covered in the course of the sampling. Because of the high turbidity of the water, only the fish that rose to the surface could be collected. Fish of each of the two size categories shown in Tables 3 and 4 were not observed on all sampling trips with the shocker; hence the difference in number of sam- ples shown in these tables. In other tests of the accuracy of mark-and-reco\ cry estimates of large- mouth bass populations, a high degree of accurac)' was reported in one pond (Carlander & Moorman 1956:663), moderate accuracy in three ponds, especially for bass more than 1 year old (Buck & Thoits 1965:606-607), and considerable inaccuracy in two ponds (Kruniholz 1944:290; Hundley 1954:167). The degiee of accuracy of the 1950 mark-and-recovery estimate of bass at Lake Glendale is perhaps fairly liigh due to the fact that the bass were concentrated in a small volume of water instead of being spread oxer the entire 82 acres. Because the bass were concentrated in a small space, there should have been the good mixing of marked and
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