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Habitat features can have a profound effect on the nesting success of birds. Savannas are often managed with predators and large herbivores as priority species, with little thought to the many bird species that management decisions could affect. Using a data set spanning seven breeding seasons, we examined how nesting success of Southern Ground-hornbills (SGHs) Bucorvus leadbeateri in the Kruger National Park varied as a result of various environmental and habitat factors within a radius of 3 km surrounding the nest site. Identifying which factors affect nesting success will allow for targeted management efforts to ensure the long-term survival of SGHs both within and outside of protected areas. Habitat structure and diversity of the vegetation surrounding the nest were the most influential factors on SGH nesting success. SGHs require open grassy areas for foraging and areas with large trees for nesting. Savanna habitat drivers such as elephants and fire should be managed to ensure that sufficient large trees are able to establish in the landscape and to control for bush encroachment. This is especially important in areas earmarked for SGH reintroductions. Nest sites of SGHs should be monitored to mitigate any structural changes in the habitat surrounding the nests. Nests should be modified or artificial nest sites provided, where nests have been damaged or lost, to ensure the continued presence of these birds in African savannas. Conservation implications: Habitat structure and diversity surrounding Southern Groundhornbill nests has a significant impact on their nesting success. This highlights the importance of monitoring vegetation change in savanna habitats where they occur. Management of savanna areas should take factors that influence bush encroachment, such as fire and elephants, into account to ensure the long-term persistence of these birds.

We report the development and validation of a highly specific heterologous radioimmunoassay (RIA) to measure meerkat prolactin (PRL) by using rabbit antiserum to human prolactin and canine [125I]iodo-PRL. Dilutions of meerkat pituitary standard and plasma gave parallel inhibition curves in the assay. Gel filtration of meerkat pituitary extracts and canine [125I]iodo-PRL run separately on a Sephadex G-100 generated identical peaks of activity, and Western blot analysis of meerkat pituitary extract with the human prolactin antiserum used in the RIA gave a molecular weight similar to canine prolactin (21 kDa). We carried out a biological validation of the prolactin assay by administering three different doses each of sulpiride and cabergoline to adult male meerkats. Increasing doses of sulpiride and cabergoline caused substantial increases and decreases, respectively, in the plasma prolactin of the study animals as expected. Activation of the stress response in meerkats by capture and ketamine hydrochloride anesthesia caused short-term but significant increases in prolactin levels in individuals bled repeatedly. The RIA developed and described here was able to determine plasma concentrations of prolactin in all animals sampled. We conclude, however, that it will be important in all future studies to confine blood sampling times to 4–7 min after capture/administration of anesthesia to avoid the confounding effects of the stress response on prolactin levels. [Copyright &y& Elsevier]

The article presents a study regarding the characterization of microsatellite loci in hybridization of honeyeater. According to the authors, they have characterized five microsatellite loci to examine the mating system of the bell miner, and surveyed the utility of the loci in other species of Meliphagidae. They revealed that the five polymorphic loci are also tested in nine other honeyeater species. They point out that only apparent predictor of variability in the nonsource species is the amount of nonspecific amplication product coamplified with the microsatellite loci. They further suggest that cross-amplifiable microsatellite loci should foster the study of honeyeaters in general.