Nest-building is an energetically expensive activity for birds. Consequently, some species opportunistically use other species' nests. The Hamerkop Scopus umbretta, an endemic sub-Saharan African waterbird, constructs one of the largest nests of any bird in the world. Little is documented on the role of Hamerkop nests in the breeding biology of other avian species. Therefore, we assessed this from the literature and first-hand observations to determine which species use Hamerkop nests and their associated behaviours. We found at least 20 avian species using Hamerkop nests for breeding in 18 African countries. The Barn Owl Tyto alba was the most commonly reported species using Hamerkop nests. Six species actively usurp nests from Hamerkop pairs. Nine species nested inside the nest chamber, and eight nested on top of the structure. This highlights the role of Hamerkop nests in other avian species' breeding.

A tag-recapture study was undertaken on Polysteganus praeorbitalis in the Pondoland Marine Protected Area (PMPA) on the east coast of South Africa. A total of 1 042 fish were tagged over a period of 16 years and 255 individuals (24.5%) were recaptured, some of them on multiple occasions. Data analysis showed that 84.7% of recaptured fish remained in relatively small home ranges (∼750 m linear distance), while 13.3% abandoned their home ranges and undertook unidirectional movements (of 21–1 211 km) along the KwaZulu-Natal coast in a north-easterly direction, most likely to spawn. While the no-take area of the PMPA provides effective protection for resident fish, the export of adult P. praeorbitalis provides strong evidence of the benefits that no-take MPAs can offer to adjacent fisheries. Based on the tag-recapture length data, the growth rate was found to be relatively slow, averaging 46 mm y^–1. This growth rate was similar to that determined by a study of ageing using sectioned otoliths. Reliable tag-recapture data can thus be used to provide a valuable means of validating growth rates determined by other methods.

Drylands correspond to ca. 40% of the world's land surface. Because of their ecological importance, these areas are regularly considered for agricultural purposes. Scorpion assemblages often exhibit higher levels of species diversity in dry habitats and are beneficial indicators in ecological studies in such environments. In this study, we investigated the effects of climatic and spatial predictors on beta diversity patterns among scorpion assemblages distributed in the drylands of Egypt. Scorpion occurrences were compiled from the scientific literature. For each location, we created a set of climatic variables related to precipitation, temperature, and solar irradiation, as well as spatial predictors. A total of 134 scorpion occurrences were obtained, comprising 21 species grouped into three families. Climatic and spatial variables together influenced the patterns of scorpion diversity in Egyptian landscapes. Species replacement accounted for 69% of the total beta diversity. In addition, species replacement was positively affected by climatic and spatial variables. Our results suggest a reciprocal link between the region's ecological history and the patterns of beta diversity observed in scorpion assemblages from Egyptian drylands.