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The Ouadi Rimé–Ouadi Achim Reserve (Réserve de l'Ouadi Rimé–Ouadi Achim) in central Chad supports large numbers of livestock and rare antelopes, and is the site of ongoing reintroductions of the scimitar-horned oryx Oryx dammah and addax Addax nasomaculatus. We present results of surveys conducted during 2011–2019 to examine patterns of relative abundance and distribution of dorcas gazelles Gazella dorcas, dama gazelles Nanger dama and livestock in relation to each other and to water sources in a 3,500 km2 area in the centre of the Reserve. Dorcas gazelles numbered 7,700–18,000, moving extensively across the area. Livestock varied between c. 2,000 and 68,000 tropical livestock units across surveys, with density doubling in the wet season. Dorcas gazelle distribution was negatively associated with livestock, and livestock density was positively associated with artificial water sources. Dorcas gazelle densities were positively associated with locations where there had been wild fires in the 6 months prior to a survey. Dama gazelles were encountered only 13 times, insufficient to estimate their population size reliably. Opportunistic observations suggest dama gazelles avoid livestock and burnt ground. Our findings highlight the importance of the Reserve. We recommend the designation of a large, well-managed conservation priority zone in the Reserve's core area in which no further development of water resources is permitted. Management of livestock numbers within this zone at or below current levels is essential to integrate national goals for both biodiversity conservation and pastoralism development.

Traditional transect survey methods for forest antelopes often underestimate density for common species and do not provide sufficient data for rarer species. The use of camera trapping as a survey tool for medium and large terrestrial mammals has become increasingly common, especially in forest habitats. Here, we applied the distance sampling method to images generated from camera-trap surveys in Dja Faunal Reserve, Cameroon, and used an estimate of the proportion of time animals are active to correct for negative bias in the density estimates from the 24-hour camera-trap survey datasets. We also used multiple covariate distance sampling with body weight as a covariate to estimate detection probabilities and densities of rarer species. These methods provide an effective tool for monitoring the status of individual species or a community of forest antelope species, information urgently needed for conservation planning and action.

Aders’ duiker Cephalophus adersi is a small antelope endemic to the coastal forests of east Africa. Threatened by habitat loss and hunting, the species is categorized as Critically Endangered on the IUCN Red List. Until recently Aders’ duiker was known to persist only on Zanzibar, Tanzania, and in the Arabuko-Sokoke Forest National Reserve, Kenya. However, in 2004 a sighting of a single individual was reported from the Dodori forest in northern coastal Kenya, raising the possibility that the species survives elsewhere. Subsequently, an opportunistic camera-trap survey was conducted in September and October 2008 to establish the occurrence of Aders’ duiker in Kenyan coastal forests north of the Tana River. One hundred and fifty six images of Aders’ duikers were obtained from 12 of 28 camera-trap sites (46 of 358 camera-trap days), confirming the existence of a population of Aders’ duiker in the Boni–Dodori forest both inside and outside the National Reserves. In addition, we sighted individuals of the species on three occasions. The relatively high encounter rates per unit effort compared to similar data from Arabuko-Sokoke forest suggest the Boni–Dodori population is significant. Initial surveys of the local Awer community revealed that Aders’ duiker is well known by the name guno. These findings significantly improve the conservation prospects for Aders’ duiker and highlight the need for greater research and management efforts in the poorly known Boni–Dodori forest.

The Barbary sheep or aoudad Ammotragus lervia is widely distributed in the mountains of the Sahara and North Africa. The 2000 IUCN Red List assessment of the Egyptian subspecies A. l. ornata categorized this taxon as Extinct in the Wild. We present new evidence, collected during 1997–2000, that this subspecies is extant in both the extreme south-east and south-west of Egypt, and reassess the status of captive aoudad in Egypt. We recommend that the category of A. l. ornata on the IUCN Red List be changed to Critically Endangered, that conservation of wild aoudad in Egypt be prioritized, and that the subspecific status of both the wild and captive stocks in Egypt be reassessed.

Assessing the biodiversity of a region, particularly when it includes rare, cryptic and nocturnal species, is notoriously difficult but nevertheless of great importance, especially in regions that have received little prior research interest. Species in these regions are often only perceived to be present through the identification of animal signs such as scat or hair. Here we show how molecular techniques can be used to sequence mitochondrial DNA extracted from the scat of essentially unknown carnivore species and thus assess the species present in a remote desert region in southern Algeria. In doing so we present a reliable and reproducible method for determining carnivore biodiversity through non-invasive sampling. We also identify two species of large carnivore in an area where one, the cheetah Acinonyx jubatus, is known to exist but at very low densities, and another, the leopard Panthera pardus, has never previously been observed.