Endangered Grevy’s zebra in the Alledeghi Wildlife Reserve, Ethiopia: species distribution modeling for the determination of optimum habitat

Abstract

Habitat loss due to human-induced factors is intensifying and is a critical threat to most endangered species. Grevy's zebra Equus grevyi is one of the most endangered mammals in the world. Human encroachment on its natural habitat and poaching are the greatest threats to this species' survival in the wild. Grevy's zebra only occur within a few isolated areas in Ethiopia and Kenya. Effective conservation interventions based on scientific information are needed to safeguard this species from extinction. Wildlife managers need to identify the extent of the remaining suitable habitat and achieve a better understanding of human and wildlife interactions if they are to facilitate appropriate conservation strategies. The present study employed the maximum entropy model (Maxent), a species distribution modeling approach, to determine the geographic extent of habitat and seasonal distribution of Grevy's zebra in the Alledeghi Wildlife Reserve, Ethiopia, and to use this information to determine the optimum demarcation of conservation boundaries. Field surveys were conducted 4 times annually, twice during the wet season and twice during the dry season, for 2 yr. Field data and predictor variables were separated into 2 seasons, and models were generated for each season independently. Seasonal maximum temperatures, distance to human settlements and slope were the best predictors for both the dry and wet seasons. Evaluations of model performances were high, with AUC (area under the receiver operating curve) values of 0.96 and 0.97 for the dry and wet seasons, respectively. Our results will be critical for modifying the existing boundaries of the Alledeghi Wildlife Reserve and directing conservation strategies for the Grevy's zebra.

Structure and regeneration status of woody plants in the Hallideghie wildlife reserve, North East Ethiopia

“…The reserve hosts ~31 and ~213 species of mammals and birds, respectively (EWNHS, 1996). At present, the reserve is home to Ethiopia's largest population of Grevy's zebra (Kebede et al, 2012).…”

“…It was established in the 1965 with the main aim to protect the endangered Gravy's zebra (Equus grevyi) and other several conservation significant mammal and bird species (Hillman, 1993;Tadesse, 2009;Kebede et al, 2012). The reserve covers an area of 1,832 km 2 and altitude ranges from 700 m to 945 m a.s.l (Hillman, 1993).…”

“…In addition to its significance for the conservation of several key wildlife species, HWR area is also the major communal livestock grazing area for Afar and Ethiopian Somali pastoral communities (Tadesse, 2009;Kebede et al, 2012). Despite its immense importance for biodiversity conservation and socio-economic development of the surrounding community, the reserve has been subjected to a number of threats, including deforestation, overgrazing, uncontrolled fire, invasion of alien plant species and bush encroachment (Tadesse, 2009).…”

“…Despite its immense importance for biodiversity conservation and socio-economic development of the surrounding community, the reserve has been subjected to a number of threats, including deforestation, overgrazing, uncontrolled fire, invasion of alien plant species and bush encroachment (Tadesse, 2009). These factors are supposed to lead to decrease in diversity and cover of native and palatable woody plant species, poor regeneration of ecologically important plant species (Khumbongmayum et al, 2006), degradation of wildlife habitats, reduced number of wild animal populations and further promotion of ecosystem invasion Endris et al 201 by exotic plant species (particularly Prosopis juliflora) in the reserve (Kebede et al, 2012). However, ecological studies on vegetation of the reserve, that would help develop and implement appropriate ecosystem and species management measures, have not been undertaken so far.…”

Integrating local pastoral knowledge, participatory mapping, and species distribution modeling for risk assessment of invasive rubber vine (Cryptostegia grandiflora) in Ethiopia’s Afar region

“…The region is topographically diverse, with elevations ranging from 125 m below sea level to 2,870 m above sea level (Wakie et al 2014), and is one of the hottest habitable places on earth, with temperatures surpassing 50°C and bimodal rainfall that is under 200 mm annually across large extents of the landscape (Davies and Bennett 2007). It holds a number of unique flora and fauna including endangered species such as the Abyssinian wild ass (Equus africanus asinus) and Grevy's zebra (Equus grevyi; Kebede et al 2012Kebede et al , 2014. Vegetation here is made up of grasses, forbs, shrubs, and woody plants, well adapted to arid and semiarid environments including Acacia mellifera, A.…”