Diet selection and foraging ecology in Macropodidae (Kangaroos)

01maart2006
Source: U. Ganslosser and D.B. Croft, University of Erlangen, University of New South Wales, Sidney.
Macropodoids posses morpho-physiological as well as ecological adaptations similar to herbivorous placentals e.g. ungulates.
Both from the morphology of dentition and jaw mechanics and from morphophysiology of stomach and gut function, at least three types of macropodids can be distinguished: browsers, intermediate feeders, and grazers. Within the potoroids (rat-kangaroos), a fourth group, the frugivores and subterraneous bulb-feeders can be found. Kangaroos and their relatives are ideally suited for studies of sex and size differences in feeding ecology, and possible influences of behavioural as well as morphological constraints acting on them. One reason for this is that most of the medium to large-sized species are heavily sexually dimorphic in size, with males growing throughout their lives. This allows an intraspecific comparison of food selection, habitat choice and foraging behaviour not only between sexes but also between age classes and, in case of females (pouch size as an indicator!), reproductive conditions. Influences of food quality and food availability on selectivity and time budgets were studied for several species of macropods, and possible consequences on social as well as reproductive behaviour will be discussed and related to captive management.