Demographics of the European hare ( Lepus europaeus) in the Mediterranean climate zone of Australia

Abstract

Demographic parameters of the European hare ( Lepus europaeus) in southern Australia were investigated by dissecting hares shot by hunters during each month of the year. Gender, body weight, age, sucking, lactation, weight of the abdominal alimentary canal, weight of the left peri-renal fat body, pregnancy status, presence and counts of placental scars, litter size, and stage of gestation were recorded. From those data, growth rates, age at weaning, age and weight at puberty, date of conception, projected birth date, recruitment, survivorship, and the relationships between lactation and fat stores and alimentary capacity were determined. Fecundity of the southern Australian hares followed the seasonal pattern reported for northern hemisphere populations. However, output was lower per female and particularly per older female. Females began breeding at an earlier age such that recruitment into the southern Australian population was more dependent on females in their first year of life than on older females. Growth rates were comparable with European rates. Although high chill factors were apparently associated with higher leveret mortality, there was paradoxically higher overall mortality during the spring-early summer period of higher plant growth than in the late summer–winter period of lower plant growth and more extreme weather conditions. Fat was accumulated during pregnancy and would act as a buffer against the possibility of inadequate food availability during lactation, but hares increased the capacity of the alimentary canal during lactation and presumably with it their ability to assimilate energy to meet the demands of lactation.