van Rensburg P.J.J., Skinner J. D. & van Aarde R. J. (1987) Effects of feline panleucopaenia on the population characteristics of feral cats on Marion Island. Journal of Applied Ecology, 24, 63-73.
(I) This paper evaluates the effects ofthe artificial introduction offcline panleucopaenia (FPL) as a primary control measure ofa feral cat population on the sub-Antarctic Marion Island (46º54'S,37º45'E).
(2) The population decreased from an estimated 3409 cats in 1977 (introduction of control factor) to 615 (S.E. = 107) cats during 1982, suggesting an annual rate of decrease of 29%.
(3) Litter size decreased and the age structure changed significantly because ofa decrease in subadult numbers. Age specific mortality rates were higher but followed the same pattern as in 1975 because there were fewer subadults but the same age structure of adults.
(4) The intrinsic rate ofincrease, as suggested by the survival and fecundity schedules of the: population, was higher in 1975 owing to a greater proportion of adults and a higher fecundity in age class II.
(5) Antibody titres of FPL were lower in 1982 than in 1978 which illustrates that FPL did affect the cat population but is no longer spreading effectively. FPL was independent of feline herpes (FVR), an endemic disease of the cat population. and FPL was, therefore, directly responsible for the decrease in cat population density.
(6) During 1982 the cat population showed a decrease of 8% year-I, whieh indicates stabilizing of the negative growth rate. This observation was supported by lower titres of FPL.
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