Observations on the Tasmanian Devil, Sarcophilus harrisi (Dasyuridae: fvlarsupiala) at Granville Harbour, 1966-75

Movements of Tasmanian devils in a western Tasmanian locality, Granville Harbour, were largely restricted to well defined trails and were related to actual or potential food sources.
The sex ratio varied greatly from year to year with the average over 10 years of 1:0.95. The percentage breeding success with females was only 58.9% with 2.67 pouch young/successful breeding female. Recruitment from this source into the adult groups is small. The population was dominated by large males for most of the period with the recruitment of young, especially of males, being low in most years. Year groups survive in the population for about 5 years. The population is maintained by immigration plus occasional good juvenile recruitment. Young females have a lower mortality than males, possibly resulting from less intraspecific interactions, but the older males have low mortality and live about 1 year longer than females.
The population increased substantially in 1973 due to a high survival of earlier year groups and a low mortality. The Granville devils appear to follow a different population cycle from that of the rest of Tasmania, due to geographic isolation.