Giraffe subspecies inbreeding themselves to extinction

Giraffes threatened with 'silent extinction'. [Reuters]

Masai giraffes, which are listed as ‘vulnerable’ and are extinct in seven African countries, may be more endangered than previously thought and are, in fact, facing a new threat to their future, a recent study reveals.

The study, published in the Ecology and Evolution journal, reveals that the Great Rift has split the subspecies in two. This has led to interbreeding, resulting in a lack of genetic flow.

“Our findings show that Masai giraffes are split into two populations and fulfill the criteria for designation as distinct evolutionary significant units (ESUs), which we denote as western Masai giraffe and eastern Masai giraffe,” the researchers say in the research article, Genetic evidence of population subdivision among Masai giraffes separated by the Gregory Rift Valley in Tanzania, published on June 12.

“While establishing giraffe dispersal corridors across the GRE is impractical, conservation efforts should be focused on maintaining connectivity among populations within each of these two populations,” the journal article reads. 

The Masai giraffe is a subspecies only found in Kenya and Tanzania. It has been declining drastically over the years. The subspecies is classified as endangered by the International Union of Conservation and Nature (IUCN) Redlist.

The Masai giraffe is also known as the Kilimanjaro giraffe, is one of the three out of nine subspecies of giraffes found in Kenya.  

Other giraffe subspecies found in Kenya include the reticulated giraffe, also known as the Somali giraffe, and the Rothschild’s giraffe, also known as Uganda or Baringo giraffe.

The subspecies occupy the savannah ecosystems of Tsavo and Amboseli National Parks, Naivasha, Magadi area and Maasai Mara National Reserve, as well as many community areas surrounding these.

Part of the Masai giraffe ranges are transboundary and straddle across the Kenya/Tanzania border. They include Tsavo National Parks in Kenya and Mkomazi in Tanzania, Amboseli National Park in Kenya and Kilimanjaro/Longido in Tanzania, Namanga/Magadi and the Maasai Mara/Serengeti ecosystems.

Rothschild giraffes on the other hand survive in Uganda, possibly in South Sudan, and have been introduced to several areas in Kenya.

In Kenya, populations of Rothschild’s giraffe were introduced into numerous private and public areas, including Giraffe Manor, Kigio Wildlife Conservancy, Lake Nakuru National Park, Mwea National Reserve,  Ruma National Park and Soysambu Conservancy.

Rothschild’s giraffe was also reintroduced to Ruko Community Wildlife Conservancy on Lake Baringo to re-establish its presence in its historical range.

Reticulated giraffes historically ranged across southern Ethiopia, northern Kenya, and east of the Rift Valley and Tana River.

Of the three subspecies in Kenya, Masai giraffes are considerably darker than the other species. The jagged-edged patches on their coats are separated by irregular, creamy brown lines that continue down below the knee. 

Although the Masai giraffe is one of the most populous giraffes in Africa with close to 32,000 individuals remaining in the wild, it was declared as endangered by the IUCN in 2019 as a result of poaching and habitat loss.