Abstract:
We studied the diet of Cape clawless otters (Aonyx capensis) at three sites along the eastern
and southern coast of South Africa to assess possible spatial variation along a community
species richness and biomass gradient associated with rocky shores.A total of 309 spraints
representing two seasons (summer 2013/2014 and winter 2014) were collected and subsequently
analysed. The percentage occurrence and percentage dry mass of numerous prey
categories were compared between sites and seasons. Variation in the importance of prey
items was found between sites, whilst no variation was found between seasons within the
same site. Crab was the most important prey item in the southernmost study area
(Tsitsikamma National Park) and at the northernmost study site (KwaZulu-Natal Coast),
whilst lobster was the most important prey item in the central area (Mkambati Nature
Reserve). Fish was the second most important prey item at all three sites. Our results
suggest that otters are opportunistic feeders that are likely able to adapt to potential prey
species and abundance changes associated with current and future anthropogenically
driven changes. Furthermore, long-term, site-specific stability in diet suggests that monitoring
the diet of otters could provide some useful information on the status of shoreline
communities.