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African elephants have major impacts on vegetation, particularly at high densities. Knob‐thorns (Senegalia nigrescens) are typically ring‐barked by elephant, and high levels of mortality are common at high elephant densities. Our study aimed to test whether ivory palm clusters (Hyphaene petersiana) form a biotic refuge for knob‐thorn against elephant herbivory. We measured the density, damage and mortality of knob‐thorns in sites differing according to ivory palm presence and elephant density, and thus, the probability of knob‐thorn encounter by elephants. The site with palms and low elephant density, had a high density of knob‐thorns, but lower proportions of damaged and dead trees, than sites without palms but with similar or higher elephant density. In the former, knob‐thorns were associated with palm clusters, particularly saplings and young adults. In this site, low proportions of damaged and dead knob‐thorns were recorded in palm clusters, compared with outside clusters, and to those in the other sites. Our study also showed that juvenile palms which protected knob‐thorns, suffered low mortality in contrast to subadult palms. We have no evidence but implicate elephants and suggest that in palm clusters, subadult palms are more accessible to elephants than knob‐thorns because of the different methods of utilisation. [ABSTRACT FROM AUTHOR]

The article focuses on the De Hoop Nature Reserve in Western Cape Province, South Africa as an important mainland habitat for the African Black Oystercatchers. A study of the diet and habitat used by the Haematopus moquini birds at the nature reserve is presented which shows the diversity and abundance of potential food items for the birds. The large brown mussel Perna perna and the white mussel Donax serra as the birds' main preys is discussed wherein increases in their modal sizes were noted. Other food sources include Cape false limpets Siphonaria spp., African periwinkle Nodilittorina africana and smooth turban shell Turbo cidaris.

The article presents a study on changes in numbers and breeding success of African Black Oystercatchers Haematopus moquini in relation to protection status and habitat quality. The researchers carried out monthly surveys from August 1984 to July 1990 and noted the numbers of oystercatcher adults, numbers of pairs and details of subsequent standardized breeding activity. They also recorded clutch replacement, egg losses and clutch sizes for each territory during the surveys. They found that the breeding success for African Black Oystercatcher populations on the Saldanha Bay islands improved between the early 1980s and 2003.