The Horn of Africa is a Conservation International Biodiversity hotspot and one of the two entirely arid ones. However, the Horn of Africa suffers largely from overgrazing, and only 5% of its original habitat remains. On Socotra, another great threat is the development of infrastructure.
About 220 mammals are found in the Horn of Africa. Among threatened species of the region, there are several antelope such as the beira, thedibatag, the silver dikdik and the Speke's gazelle. Other remarkable species include the Somali wild ass, the desert warthog, the Hamadryas Baboon, theSomali pygmy gerbil, the ammodile, and the Speke's pectinator. The Grevy's zebra is the unique wild equid of the region. The endangered Painted Hunting Dog had populations in the Horn of Africa, but pressures from human exploitation of habitat along with warfare have reduced or extirpated this canid in this region.
Some important bird species of the Horn are the Bulo Burti boubou, thegolden-winged grosbeak, the Warsangali linnet, or the Djibouti Francolin.
The Horn of Africa holds more endemic reptiles than any other region in Africa, with over 285 species total (and about 90 species found exclusively in the region). Among endemic reptile genera, there are Haackgreerius, Haemodracon, Ditypophis, Pachycalamus and
Aeluroglena. Half of these genera are uniquely found on Socotra. Unlike reptiles, amphibians are poorly represented in the region.
There are about 100 species of freshwater fish in the Horn of Africa, about 10 of which are endemic. Among the endemic, the cave-dwelling Somali blind barb and the Somali cavefish can be found.
It is estimated that about 5,000 species of vascular plants are found in the Horn, about half of which are endemic. Endemism is most developed in Socotra and northern Somalia. The region has two endemic plant families: theBarbeyaceae and the Dirachmaceae. Among the other remarkable species, there are the cucumber tree found only on Socotra (Dendrosicyos socotrana), the Bankoualé palm, the yeheb nut, and the Somali cyclamen.
Drought is a predictable event in the Horn of Africa's semi-arid and aridclimate, however climate change and changes in agricultural practices have exacerbated the impact. For centuries the region's pastoral groups have observed careful rangeland management practices to mitigate the effects of drought, such as avoiding overgrazing or setting aside land only for young or ill animals. However, population growth has put pressure on limited land and led to these practices no longer being maintained. Droughts in 1983–85, 1991–92 and 1998–99 have caused long periods of gradual growth in herd numbers to be destroyed very quickly, leading to between 37% and 62% of the cattle population perishing, mostly from starvation.The monetary value of the losses of those three droughts are estimated to be US $6,523 per household (US $893 per person), while overall losses on the Borana plateau may be as high as US $300 million. Recent initiatives have sought to reverse the trend:
- Pastoralist Livelihoods Initiative (PLI), a two-year programme funded by USAID
- Enhanced Livelihoods in the Mandera Triangle/Southern Ethiopia (ELMT/ELSE) programme, a crossborder initiative funded by USAID and a consortium of NGOs including CARE International
- Regional Resilience Enhancement Against Drought (RREAD) programme, funded by the European Commission Humanitarian Aid Office (ECHO) and implemented by CARE International
These initiatives have reclaimed hundreds of hectares of pastureland through rangeland management, leading to the establishment of the Dikale Rangeland in 2004, which now serves over 150 pastoralist households, feeding more than 400 calves and small animals over a period of three months.