The arid Horn of Africa has been a renowned source of biological resources for thousands of years. One of only two hotspots that is entirely arid, the area is home to a number of endemic and threatened antelope, notably threatened species like the beira, the dibatag, and Speke’s gazelle.
This hotspot also holds more endemic reptiles than any other region in Africa. Other distinctive endemics include the Somali wild ass and the sacred baboon.
Unfortunately, The Horn of Africa is also one of the most degraded hotspots in the world, with only about 5 percent of its original habitat remaining. Overgrazing is the most destructive force, but charcoal harvesting along with unstable government control have also been major problems.
VITAL SIGNS
| Hotspot Original Extent (km²) |
1,659,363 |
| Hotspot Vegetation Remaining (km²) |
82,968 |
| Endemic Plant Species |
2,750 |
| Endemic Threatened Birds |
9 |
| Endemic Threatened Mammals |
8 |
| Endemic Threatened Amphibians |
1 |
| Extinct Species† |
1 |
| Human Population Density (people/km²) |
23 |
| Area Protected (km²) |
145,322 |
| Area Protected (km²) in Categories I-IV* |
51,229 |
†Recorded extinctions since 1500. *Categories I-IV afford higher levels of protection.
OVERVIEW
The Horn of Africa has been a renowned source of biological resources for thousands of years. The ancient Egyptians, Greeks and Romans sent expeditions and caravans to the region for frankincense, myrrh and other natural commodities to be taken back North along the incense route through the Arabian deserts.
Centered on the arid Horn, east of the Ethiopian Highlands, this hotspot also covers the Rift Valley, which divides the Ethiopian Highlands into two major blocks, the xeric bushlands of northeastern Kenya and the southern coastal parts of the Arabian Peninsula. Politically, this includes most of Somalia, all of Djibouti, parts of Ethiopia, Eritrea, Kenya, Yemen and Oman, and a small piece of far eastern Sudan. Also included in this hotspot are the Socotra Archipelago off the coast of northeastern Somalia, and a few hundred tiny islands in the Red Sea.
Although the entire hotspot covers more than 1.5 million km², a relatively large portion of the land area has very limited flora (for example, the Danakil Depression), and most of the plants known from the region actually occupy only a small percentage of the area. The dominant vegetation type is Acacia-Commiphora bushland, although evergreen bushland, succulent shrubland, dry evergreen forest and woodland, semi-desert grassland and low-growing dune and rock vegetation also occupy portions of the region. Small areas of mangrove are found on both the African and Arabian sides of the hotspot, as well as riverine vegetation along major rivers such as the Wabe Shabelle and Awash.
The Horn of Africa is one of only two hotspots that is entirely arid; the other is the Succulent Karoo in southwestern Africa. It is believed that these two arid regions were united by an “arid corridor” during drier and colder periods in the Pleistocene, and possibly also in the earlier Tertiary. Several genera of flowering plants are entirely restricted to just these two regions, such as Kissenia, with one species in the arid Horn and one in the Succulent Karoo, and Wellstedia with six species in the arid Horn and one in the Succulent Karoo.