Lake Guntersville Largemouth Bass

  1. A total of 23 fish were caught per hour in the first sample.
  2. The catchability coefficient (q) is estimated to be 0.190 with a 95% confidence interval from 0.058 to 0.322. Thus, it is estimated that 19.0% of the Largemouth Bass (Micropterus salmoides) in the enclosures would be captured with one hour (i.e., one unit) of electrofishing effort. This value is the same as that reported in Maceina et al. (1995).
  3. The initial population size (N0) is estimated to be 108 with a 95% confidence interval from 58 to 159. This value is the same as that reported in Maceina et al. (1995).
  4. One would expect to catch 0.190×108.4×1 = 20.6 fish in the first hour of sampling.
  5. To compute the expected catch for the second sample, one must first reduce the original population size by the number of fish removed with the first sample (i.e., N0-N0×q×1) and then multiply that times q×1. Thus, the expected catch for the second sample is (108.4-20.6)×0.190×1 = 16.7 fish.

R Appendix

d <- data.frame(ct=c(23,12,13,14,9,7),
                ft=rep(1,6)) %>%
  mutate(CPE=ct/ft)
depl1 <- depletion(d$ct,d$ft,method="Leslie")
summary(depl1)
confint(depl1)