Mortality factors acting on adult rabbits in central-western New South Wales

Mortality of radio-tagged adult rabbits (Oryctolagus cuniculus) (n = 274) w as monitored for one year in central-western New South Wales. The overall m ortality rate was 82%. Predation was the most important and consistent caus e of adult rabbit mortality, accounting for 44% of the total number of rabb its, followed by Rabbit Haemorrhagic Disease (RHD) (16%), myxomatosis (9%), unknown causes (9%), and enteritis/peritonitis (2%). Foxes were the most i mportant predators, accounting for 28% of radio-tagged rabbits. Medium to l arge birds of prey were less important, accounting for 10%, followed by cat s, which were responsible for 6% of the deaths of radio-collared rabbits. M yxomatosis outbreaks occurred in February/March and November-January. An RH D outbreak occurred during July, with 40% of the adult rabbit population be ing killed. The number of male and female radio-collared adult rabbits kill ed by each mortality agent throughout the year was similar. The proportions of warren-dwelling rabbits and surface-dwelling, solitary rabbits killed w ere similar overall; however, a significantly higher number of warren-dwell ing rabbits were killed by myxomatosis and a significantly higher number of surface-dwelling rabbits were killed by RHD.