Relative population sizes and trends, and hybridization of fur seals Arctocephalus tropicalis and A. gazella at the Prince Edward Islands, Southern Ocean

Fur seals were counted at the Prince Edward Islands during the 1981/1982 austral summer. Classified counts, adjusted for pup undercounting and mortality, pregnancy rate and seasonal haul-out patterns, of Arctocephalus tropicalis and A. gazella are presented. These populations have entered a phase of rapid growth, as indicated by higher rates of population growth than previously found. The possible role of A. gazella immigration is unknown. There has been an increase in the number of breeding localities used by both species. At present the extent of hybridization between these two species appears limited, possibly by behavioural, ecological and genetic processes

Browsing by Lepus capensis in the Karoo

Although previously described as a grazer, Lepus capensis utilizes browse extensively in the Karoo. Observations of dietary selection by this species in the Karoo are presented, and potential competition with stock farmers is suggested

Faunal changes along a vegetation gradient in the Alexandria Coastal Dunefield, South Africa

Coastal dunes are distinguished by their border with the sea and the resultant abiotic and vegetation gradients perpendicular to the shore. This study, conducted in the Alexandria dunefield, tested the prediction that faunal community changes along a dunefield gradient reflect successional changes in vegetation structure. Three sites at increasing distances from the shore were examined: a vegetated dune slack, a bushpocket and dune thicket. Vegetation complexity increased inland, although the slack and pocket were similar. Arthropod and small mammal richness and diversity were highest in the thicket and lower, but similar, in the slack and bushpocket. Avifau-nal species richness increased away from the sea. The results support the hypothesis of faunal response to vegetation structure changes

Dietary patterns of two herbivorous rodents:

Differences and overlap in the diets of two sympatric, herbivorous rodents Otomys unisulcatus and Parotomys brantsii were investigated. Frequency of occurrence of plant species in the diets were compared with availability of the plants in the rodents' habitats. Both rodents are generalist herbivores, eating plants species in proportion to the availability in their habitats. Dietary patterns, diversity of diet and degree of overlap between rodent's diets are a function of food availability in the different habitats. It is suggested that these rodents separate niches on a spatial rather than trophic basis. Differences in dietary patterns are therefore not critical for niche separation but are the result of habitat segregation

Animal welfare considerations for using large carnivores and guardian dogs as vertebrate biocontrol tools against other animals

Introducing consumptive and non-consumptive effects into food webs can have profound effects on individuals, populations and communities. This knowledge has led to the deliberate use of predation and/or fear of predation as an emerging technique for controlling wildlife. Many now advocate for the intentional use of large carnivores and livestock guardian dogs as more desirable alternatives to traditional wildlife control approaches like fencing, shooting, trapping, or poisoning. However, there has been very little consideration of the animal welfare implications of deliberately using predation as a wildlife management tool. We assess the animal welfare impacts of using dingoes, leopards and guardian dogs as biocontrol tools against wildlife in Australia and South Africa following the ‘Five Domains’ model commonly used to assess other wildlife management tools. Application of this model indicates that large carnivores and guardian dogs cause considerable lethal and non-lethal animal welfare impacts to the individual animals they are intended to control. These impacts are likely similar across different predator-prey systems, but are dependent on specific predator-prey combinations; combinations that result in short chases and quick kills will be rated as less harmful than those that result in long chases and protracted kills. Moreover, these impacts are typically rated greater than those caused by traditional wildlife control techniques. The intentional lethal and non-lethal harms caused by large carnivores and guardian dogs should not be ignored or dismissively assumed to be negligible. A greater understanding of the impacts they impose would benefit from empirical studies of the animal welfare outcomes arising from their use in different contexts

Record for the Cape fur seal Arctocephalus pusillus pusillus from subantarctic Marion Island

No Abstract

Potential distributions of the medium- to large-sized mammals in the Cape Floristic Region, based on historical accounts and habitat requirements

Conservation planning in the Cape Floristic Region, a recognized world plant diversity hotspot, required systematic (i.e. presence/absence) information on the estimated distributions of the medium- to large-sized mammals. A pragmatic approach for obtaining distribution estimates, for the period prior to arrival of European settlers, was employed. Distribution estimates were based on a combination of a literature survey (with emphasis on early texts) and the ecological requirements of species, and were mapped within each of 102 Broad Habitat Units delineated according to key biophysical parameters. The estimated distributions of 42 species are provided in the form of maps; these are accompanied by brief notes on historical and current occurrences. The distributions, which can be used to guide conservation decisions, should be considered as testable hypotheses.Key words: Cape Floristic Region, distributions, mammals, habitats

Dietary shifts: do grazers become browsers in the Thicket Biome?

The diet of buffalo (Syncerus coffer) and Burchell's zebra (Equus burchelli) was investigated in the Addo Elephant National Park to test the hypothesis that the shortage of grass associated with thicket vegetation results in grazers increasing the proportion of dicotyledonous plant species in their diet. Diet composition, estimated from faecal analysis, indicated that 19 and 21 plant species were identified in the faeces of zebra and buffalo, respectively. Buffalo proved to have a higher percentage dicotyledonous (28.1 vs. 8.5 ) and lower percentage monocotyledonous (71.9 vs. 91.5 ) species in their diet than zebra. The grass Eragrostis curvula was found to be the dominant food item for both buffalo (18 of diet) and zebra (39 of diet) during the period of study. The present study indicated that a great proportion of the buffalo diet does in fact consist of grass, thereby refuting the perception that the Addo buffalo are primarily browsers. Both buffalo and zebra are specialised grazers and unsuited to a diet of browse. The probability of dietary shift by these grazers in the grass limited thicket vegetation is therefore challenged

The winter diet of elephant in Eastern Cape Subtropical Thicket, Addo Elephant National Park

Direct observational methods were used to establish the winter diet of elephants in Eastern Cape Subtropical Thicket in the Addo Elephant National Park, thereby determining which plant species were most at risk from elephant herbivory. A total of 70 species were identified as food plants for elephants, with the grass Cynodon dactylon and the succulents Portulacaria afra and Platythyra haeckeliana dominating, both in terms of frequency of feeding events and volume consumed. In view of the fact that elephants represent 78 of the herbivore biomass in the park, it appears likely that elephant feeding restricts the availability of forage for other browsers. Due to the limited time frame of this study, further research is needed to provide a comprehensive record of the elephant diet for all seasons of the year