Freshwater availability and distribution of Cape clawless otter spraints and resting places along the south-west coast of South Africa
This paper relates use of the marine habitat by Aonyx capensis, as shown by the use of resting and sprainting sites, to the presence or absence of fresh water. This paper tests the null hypothesis that spraints and couches of A. capensis are randomly distributed with regard to freshwater availability. Dependence on freshwater sources by coastal A. capensis has important conservation implications. Reduced stream flow or seasonal drying up of sources, resulting from increased human activities, can negatively affect continued otter occurrence along a coastline. Occurrence of spraints, couches and resting places along the south-west coast, South Africa, was found to be closely tied to freshwater sources. It is hypothesised from the results of this study that A. capensis, like the Eurasian otter Lutra lutra, needs fresh water to use marine habitats. The results indicate that monitoring freshwater points along similar coasts would indicate whether otters were present in the general area or not - a time-saving method of determining otter distribution on a large scale. Monitoring only mouths of rivers is possible, as most spraints and couches were located very close to fresh water.