Relationships between food quality and reproductive success in female red-necked wallabies Macropus rufogriseus banksianus

Abstract

This study indicates that even in the absence of oven intraspecific competition, fine-scale spatial variation in food quality can lead to individual variation in reproductive success. Life history data on individual female red-necked wallabies Macropus rufogriseus banksianus were obtained over a six-year period. Vegetation surveys were conducted to analyse the composition of vegetation in the feeding range of each female, from which individual food quality indices were derived. Females' rates of rearing offspring to permanent emergence from the pouch and to weaning were positively correlated with the quality of food in their feeding ranges. Time spent in the pouch by offspring and age at first parturition of daughters were negatively correlated with maternal food quality. It is proposed that quality of available food affects growth rates and survival of offspring through its effects on maternal lactation and/or forage intake by offspring.