Successful conservation of large mammals requires vast areas to maintain viable populations. This often requires to embrace large-scale approaches that extend beyond the borders of formally protected areas. However, the quality of the scientific knowledge about animal movement across large conservation areas vary, and could limit the effectiveness of conservation efforts. Here we used GPS tracking to conduct the first study of large-scale movements of African elephants (Loxodonta africana) in Hwange NP (Zimbabwe), which is an unfenced park part of the Kavango-Zambezi Transfrontier Conservation Area, the world's largest terrestrial conservation area. We show that some, but not all, elephants migrate seasonally, with wet- to dry-season movements linked to the provision of water in Hwange NP. The distance between the most distant locations of individual elephants reaches 260 km. In this partial migration system influenced by management practices, over 20% of the elephants have wet-season ranges established in Botswana, outside of protected areas in private or communal wildlife management areas. Our results call for the urgent drafting of a regional action plan, involving all stakeholders identified by our study and their neighbours, to predict and react to what would happen if water provision in Hwange NP was to suddenly change because of management practices or extreme climate change. Beyond this critical conservation issue for the world's largest elephant meta-population, our results also highlight the relevance of large-scale conservation areas combined with integrative planning involving national wildlife management institutions and the private and communal sector. (Résumé d'auteur

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In order to better understand the symbiotic relationship of the oxpecker-mammal association and the role that oxpeckers play in controlling their hosts' tick burdens, interactions between yellow-billed oxpeckers (Buphugus ufricanus) and impala (Aepyceros melumpus) were investigated at Matobo National Park, Zimbabwe during the wet and dry seasons. Oxpeckers devoted 30-35% of attendance time to foraging upon impala hosts. The ears were preferred for foraging above all other body regions, and foraging sessions directed to the ears were longer than sessions on other areas, apparently due to high tick infestation on host ears. Two-thirds of adult ticks (mostly the blue tick Boophilus decolorutus) collected from impala females were from the ears, and heavy infestations of immature ticks on the ears were common. The majority of oxpecker foraging (71-74%) was directed to the ear, head, and neck area where impala are unable to self-oral groom. Most adult ticks (75-77%) were found on the ears, head, and neck of sampled impala, indicating that oxpeckers foraged so as to maximize adult tick intake. Adult tick abundance in the vegetation, and presumably on impala, was much greater in the wet season than in the dry season. Oxpeckers spent significantly less time foraging upon impala in the wet season compared with the dry season, reflecting the presumed greater abundance of adult ticks on hosts during this time. Impala hosts tolerated oxpeckers 86% of the time, and 42% of oxpeckertolerant impala accommodated foraging activity by lowering an ear, inclining the head, or standing still. An interaction was apparent between the tick-removal strategies of oxpeckers and their impala hosts in that impala reduced their grooming rate when oxpeckers foraged upon them to 11-36% of their grooming rate in the absence of oxpeckers, thereby reducing the cost of tick control.Pour mieux comprendre la relation symbiotique de l'association pique-boeufsmammifkres et le rdle que jouent les pique-boeufs dans le contr6le des tiques de leurs hdtes, on a analyse les interactions entre les pique-boeufs a bec jaune Correspondence: Michael S. Mooring, Interactions between impala and oxpeckers 55 (Buphagus ufricanus) et les impalas (Aepyceros melampus) au Parc National deMatobo, au Zimbabwe, en saison sbche et en saison des pluies. Les pique-boeufs consacraient de 30 a 35% de leur temps d'attention a se nourrir sur des impalas.11s preferaient les oreilles a toute autre partie du corps et le temps consacre a se nourrir sur les oreilles Ctait plus long que sur toute autre partie du corps, ceci &ant dti semble-t-il a un plus haut degrC d'infestation des oreilles des hates par les tiques. Les deux tiers des tiques adultes (surtout la tique bleue Boophilus decoloratus) recoltkes sur les impalas femelles provenaient des oreilles, et de fortes infestations des oreilles par des tiques immatures sont communes. La plus grande part des recherches de pique-boeufs (71 a 74%) se faisait au niveau des oreilles, de la t&te et du cou, la ou les impalas sont incapables de s...

The White‐headed Vulture Trigonoceps occipitalis (WhV) is uncommon and largely restricted to protected areas across its range in sub‐Saharan Africa. We used the World Database on Protected Areas to identify protected areas (PAs) likely to contain White‐headed Vultures. Vulture occurrence on road transects in Southern, East, and West Africa was adjusted to nests per km2 using data from areas with known numbers of nests and corresponding road transect data. Nest density was used to calculate the number of WhV nests within identified PAs and from there extrapolated to estimate the global population. Across a fragmented range, 400 PAs are estimated to contain 1893 WhV nests. Eastern Africa is estimated to contain 721 nests, Central Africa 548 nests, Southern Africa 468 nests, and West Africa 156 nests. Including immature and nonbreeding birds, and accounting for data deficient PAs, the estimated global population is 5475 ‐ 5493 birds. The identified distribution highlights are alarming: over 78% (n = 313) of identified PAs contain fewer than five nests. A further 17% (n = 68) of PAs contain 5 ‐ 20 nests and 4% (n = 14) of identified PAs are estimated to contain >20 nests. Just 1% (n = 5) of PAs are estimated to contain >40 nests; none is located in West Africa. Whilst ranging behavior of WhVs is currently unknown, 35% of PAs large enough to hold >20 nests are isolated by more than 100 km from other PAs. Spatially discrete and unpredictable mortality events such as poisoning pose major threats to small localized vulture populations and will accelerate ongoing local extinctions. Apart from reducing the threat of poisoning events, conservation actions promoting linkages between protected areas should be pursued. Identifying potential areas for assisted re‐establishment via translocation offers the potential to expand the range of this species and alleviate risk.

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In eastern and southern Africa, some ranch owners are now keeping cattle overnight in temporary corrals (hereafter referred to as kraals) within rangelands for short durations to improve grass production. However, this has profound effects on the woody plant community. For instance, cattle break woody plant stems and strip them of foliage, initiating resprouting. The resprouts produced have high foliar nitrogen (N) and reduced condensed tannin (CT) concentrations, making them attractive to herbivores. The aim of this study was to determine the key nutrient-quality parameters of resprouts that make previously kraaled sites attractive to impala soon after cattle removal at Debshan Ranch in central Zimbabwe. We determined resprout length, foliar N, phosphorus (P), potassium, CT, fibre and rumen fermentation of three browse species, viz. Grewia monticola Sond., Terminalia sericea Burch. ex DC. and Dichrostachys cinerea (L.) Wight and Arn., and related them to impala use of previously kraaled sites. We used impala dung density to determine the use patterns of previously kraaled sites 2, 4, 12 and 24 weeks after cattle removal and compared them with the surrounding vegetation. Impala use of previously kraaled sites was highest 4 weeks after cattle removal and lowest in the surrounding vegetation. Resprout length increments were 6-fold over a 10-week growth period in all three woody species. Foliar N and P were generally higher, whereas CT was lower, in previously kraaled sites than the surrounding vegetation in all three of the plant browse species. Impala use of previously kraaled sites showed a strong negative relationship with foliar CT. We conclude that kraaling initiates strong resprout responses by woody plants soon after cattle removal, to produce resprouts of high nutrient quality, which attract herbivores such as impala.

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The spatial and temporal structures of waterbird communities are dynamic and complex with many driving factors. We used long-term waterbird census data at two lakes in Zimbabwe to explore the ecological and anthropogenic drivers of waterbird community composition and abundance. Ecological drivers predicted to influence waterbird communities include rainfall quantity and distribution, waterbird movement, breeding and moulting; anthropogenic drivers include activities such as fishing and agriculture. Results suggest that seasonal variations in resource availability influenced the waterbird community composition and abundance, as did movements at local, regional, and intercontinental scales. Bird numbers in the two perennial lakes experienced large changes in structure during two droughts. We also used the study as a baseline for considering the risk of spread of avian influenza virus (AIV) spread in waterbird communities in Zimbabwean lakes, which is likely to be higher in dry seasons and during drought years when waterbird abundance is high. Our study emphasises the importance of long-term ecological data in understanding crucial aspects of biodiversity conservation as well as pathogen dynamics in wild waterbird communities, with important management implications.