Journal ofApplied Ecology (1983), 20,707-712 OBSERVATIONS ON THE TREND OF THE BREEDING POPULATION OF SOUTHERN ELEPHANT SEALS, MIROUNGA LEONINA, AT MARION ISLAND

• Main Authors: J. D. Skinner, R. J. Van Aarde
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Elephant Seal; Elephant Seals; Marion Island; Mirounga leonina; Southern Elephant Seal; Southern Elephant Seals
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.499.917; http://www.ceru.up.ac.za/downloads/Observations_trend_breeding.pdf

(I) The annual haulout pattern of adult southern elephant seal cows is described by polynomial functions with differences in the rate of haulout and the asymptote attained resulting in the coefficients and constants of the functions being different. (2) An analysis of data collected during nine breeding seasons from 1973 to 1982 indicated an overall decrease of 11 · 0 and 8 · O'ib for the adult bull and cow components of the population breeding at Marion Island. 0) The number of cows hauling out to produce pups is exponentially related to the number of adult bulls present on land during the year of fertilization. The overall decrease in the population may therefore be ascribed to factors responsible for a decrease in bull numbers.