Two male and three female caracal Felis caracal were radio‐tracked over a 1‐year period in arid shrub on the west coast of South Africa, by day and night over at least 130 days for each caracal, and uninterrupted for up to 120 h at a time. These results, on short‐term use of space, were related to concurrent availability of prey. The use by caracal of specific plant communities showed a significant positive correlation to prey biomass of rodents. Males had much larger home‐ranges (26.9±0.75 km2) than females (7.39±1.68 km2). Male home‐ranges overlapped completely with those of females, whereas female ranges overlapped between 0 and 19%. Caracal were active by night and day; onset of activity was affected more by ambient temperature (TA) than photoperiod. Caracal were active significantly longer on nights colder than 20°C. Females ceased activity at TA > 20°C, males at TA > 22°C. Males foraged faster than females (667 vs. 312 m h−1) and moved more than twice the distance of females during an active period. Calculated density of caracal was between 0.23 and 0.47 km−2.

Black‐backed jackals Canis mesomelas were studied in three areas in Southern Africa, by means of radio tracking, visual observations and ear tagging. Jackal pups moved from the close proximity of their natal dens at 3 months of age, but stayed in the vicinity of the dens for at least 6 months. Dispersal often occurred at an age of about 2 years, mainly during the winter. Adult jackals had smaller home ranges than younger animals. Adult home ranges were inhabited by mated pairs. These ranges were mutually exclusive and differed in size between study areas. The home ranges of immature jackals overlapped extensively with those of the adult jackals. Some young jackals acted as helpers in rearing the pups at natal dens, while others roamed over large areas. Adult jackals move over longer daily distances than did younger animals. The significance of the division of Black‐backed jackal populations into breeding and non‐breeding components is discussed as well as the similarities among the social systems of Canis mesomelas. C. aureus and C. latrans.

Since the canids and felids diverged in the mid-Eocene or earlier, each family has developed a suite of morphological and behavioural adaptations for obtaining and consuming prey. We here distinguish between prey taxa captured and eaten as a result of these phylogenetic adaptations, and those because they are fortuitously encountered, and argue that such supplementary prey, often opportunistically caught, create a buffer between sympatric, and potentially competitive, canids and felids and thus enhance coexistence. We base our analysis on dietary data derived from the stomach contents of four sympatric canid and felid species in the Free State Province, South Africa (canids: Cape fox Vulpes chama and black-backed jackal Canis mesomelas ; felids: African wild cat Felis silvestris lybica and caracal Caracal caracal ), and from results of studies on these species elsewhere in southern Africa. The two canid species preyed heavily on invertebrates, and thus opportunistically, while the felids (especially the caracal) concentrated on mammals, prey they are phylogenetically adapted to capture. Only three species of mammalian prey are shared by the four species. The ratio of opportunistically-to-phylogenetically mediated prey taxa used (the O/P ratio) differ between the species, with the black-backed jackal having the most opportunistically caught taxa in its diet, and the caracal the least. As predicted, a comparison of this data with those from dietary studies of the same species carried out elsewhere indicates that the number of opportunistically obtained prey taxa varies more than those resulting from phylogenetic adaptations. The largest canid had the widest food spectrum (35 prey taxa) while the smallest felid had the most restricted one (11 prey taxa). We argue that using the O/P distinction allows a better understanding of changes in food niche breadth of particular species, especially in xeric areas, and gives a better indication of possible exploitative competition for food by sympatric carnivores than when regarding all prey taxa as actively pursued.

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We radio‐tracked seven Cape clawless otters (Aonyx capensis) (Schinz, 1821) in two rivers in the Western Cape Province, South Africa, providing data on their habitat selection. Habitat type was investigated at a scale that enabled us to separate the effects of types of riparian vegetation, geomorphology and anthropogenic influences. Otters selected areas with boulders and/or reed beds, which provided high crab density and shelter. Direct observations showed that they used two foraging modes depending on the habitat selected. Otters could select open water within c. 8 m of the shore, dive and surface with or without prey. Otherwise hunting involved them moving into shallow water (c. 0.2 m deep), and walking along the substrate feeling for prey with their forefeet. Disturbed possible prey items were then caught with the forefeet.

Bat-eared foxes Otocyon megalotis feed in pairs or groups of three when utilizing clumped prey in patches, e.g. termites, and cover 0,87-1,28 km/h. When feeding on dispersed prey, e.g. insect larvae, they are widely spaced and cover 0,56-0,83 km/h. Food patches are never re-utilized on the same day. Patch size diameter varied from 6-30 m, and patches were 10 to > 100 m apart, while from 1,17 min to 15 min were spent in patches. There were no significant correlations between patch size and distance moved to next patch, or time spent in a patch and distance moved to next patch, or time spent in a patch and patch size. Patches were seldom (1,6 ) returned to immediately. A male and a female had similar numbers of feeding bouts per sampling period during winter or summer, but when accompanied by cubs the male fed less frequently. The male had significantly longer feeding bouts than the female in winter, with the reverse applying in summer. Within-sex comparisons show that the number of feeding bouts of the male did not vary significantly between winter and summer. Conversely the female showed significant differences in the number but not the duration of feeding bouts in winter and summer. Optimal foraging in this species probably relates to prey profitability, i.e. highest ingestion rate.

To determine the effects of their movement patterns, seven Cape clawless otters Aonyx capensis were caught in two rivers and radio-tracked between 1993 and 1995. Total range length varied from 4.9 to 54.1 km and core length from 0.2 to 9.8 km. Total area of water used varied between 4.9 and 1062.5 ha, and core areas from 1.1 to 138.9 ha. As predicted using the resource dispersion hypothesis, total home-range length was correlated with mean reed bed (high food density patch) nearest neighbour distance. The pattern of home-range use by females was suggestive of territoriality. Male Cape clawless otters had overlapping home ranges, both with other males and with females.

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