The Diets of Two Coexisting Species of Antechinus (Marsupialia: Dasyuridae).

Abstract

An analysis of faecal samples and stomach contents of Antechinus stuartii and A. swainsonii inhabiting forest in southern Victoria revealed a large overlap in the type and size of prey items taken by these dasyurids. The frequencies of 23 prey types and 15 prey sizes in the diets of these predators were both positively correlated. Weevils (Coleoptera, Curculionidae) represented the only difference in prey types not attributed to individual variations. A. stuartii took more, and a wider size range of, weevils than did A. swainsonii; the trophic diversity index of prey types was greater for A. stuartii. The larger A. swainsonii took more prey greater than 20 mm; it took prey on the average 23% longer and 75% heavier than did A. stuartii; the trophic diversity index of prey size was greater for A. swainsonii. It is concluded that these morphologically distinct predators are exploiting the same large population of prey. They are both generalists and appear to be opportunistic feeders.