The response of grey (Sylvicapra grimmia) duikers to conspecific faecal deposits: possible territorial implications
Duikers are becoming increasingly threatened, primarily due to hunting for bushmeat. In Zimbabwe, recent economic decline has led to very significant increases in bushmeat hunting and trade; possibly even to the extent to cause local extinction of the usually abundant grey duiker (N.Lunt unpubl. data). Duikers are very poorly studied and more information is needed to develop effective monitoring systems and conservation plans. Territorial behaviour is particularly important as estimates of territory size and degree of overlap are often used to determine density of individuals. Dambari is the headquarters of the Marwell Zimbabwe Trust and holds a large collection of small antelope including many grey duiker. It provides an ideal situation to test hypotheses about these small, secretive animals in semi-natural conditions.
Grey duikers (Cephalophini: Sylvicapra grimmia) are territorial antelope that use olfactory means to demarcate territorial boundaries.
The role of faeces in territorial behaviour was investigated using semi-captive antelope at Dambari Field Station, Zimbabwe. The strength of response to introduced faecal deposits of various ages from unfamiliar conspecifics of both sexes and three age classes was measured using a repeated measures design. Latrine sites, faecal pile dry mass and defecation rates did not alter with introduction of unfamiliar faecal piles, and fresh mass of introduced faeces did not affect response magnitude. Dung of intermediate age elicited the greatest response, and animals responded most intensely to the dung of animals in their prime. Adult male and female response frequency was not statistically different, although males responded to fresher dung than did females and only adult males scent-marked near introduced deposits. Adults showed greater interest in introductions than juveniles. It is concluded that faecal piles act as both olfactory and visual signals, and that the differences between sexes in the types and magnitude of response are related to territorial behaviour.
