Feeding ecology and diet

The huge range of body sizes in the Dasyuridae means that diet encompasses a broad range of invertebrate and vertebrate prey sizes. Prey size increases with body size. Dasyurids that are less than 5.2 oz (150 g) in body size are mostly insectivorous, although they may kill and eat small mammals, lizards, and frogs, and eat carrion of larger species if it is available. Carnivory (consumption of vertebrate prey) gradually replaces insectivory as body size increases. At approximately 2.2 lb (1 kg), dasyurids become too large to support themselves primarily on invertebrates, and carnivory takes over as the

A red-tailed phascogale (Phascogale calura) eats a gecko (Gymnodacty-lus sp.). (Photo by Eric Lindgren/Photo Researchers, Inc. Reproduced by permission.)
Brush-tailed phascogales (Phascogale tapoatafa) prefer Australia's eucalyptus forests for foraging and nesting sites. (Photo by Michael Mor-combe. Bruce Coleman, Inc. Reproduced by permission.)

arid zone animals; very little is known of the New Guinean species. Most Australian dasyurids are seasonal breeders, and probably promiscuous. Reproduction is tightly synchronous (three to four weeks) in many temperate species, particularly the semelparous antechinuses and phascogales, but can extend over a number of months in arid zone animals. New Guinean dasyurids from wet tropical forests, for the two species of Murexia and one species of Phascolosorex, breed year-round. Changes in photoperiod seem to be the most important force driving timing of reproduction, which is consistent with asea-sonal breeding in the wet tropical forests. In arid areas, rainfall events are important in defining the precise timing of reproduction within the broader seasonal window. This flexibility in arid-zone species enables reproduction to be synchronized with maximal food supply after rain, as breeding in predictably seasonal regions is timed so that young emerge in the late spring food flush.

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