Africa
Africa's lion populations on death row

afrol News, 23 August - Once inhabiting the entire continent, the king of Africa's mammals is set to disappear from all but the south and east, environmentalists warn. Already exterminated in North Africa, lion populations in West and Central Africa seem too small to secure the predator's survival there. 

Eastern and Southern Africa, with its extensive protected areas and strict conservation regimes, are the only areas where the survival of the lions seems secured. Here, populations are big enough and sufficiently interconnected to safeguard genetic variety and therefore reproduction and survival. 

According to studies published in 'New Scientist' and 'Science', the lions' reproduction efforts are jeopardised in other parts of the continent. Data produced by a study led by the International Union for Conservation of Nature (IUCN) showed that there did not exist any lion population in West and Central Africa, big enough to secure long time survival. 

Biologists assess that a population of between 500 and 1000 animals is necessary to safeguard the long term survival of lions in an area. Most lion populations in West and Central Africa however typically only include some 50 animals. Contact with neighbouring populations is interrupted by man's landuse. 

Even the biggest populations in West and Central Africa are far below the estimated minimum size. These include an isolated population in Bouba Ndjida in Northern Cameroon and another population in the Fouta Jallon highlands on the border between Senegal, Guinea and Mali. Both populations are estimated at some 200 animals and human settlements are constantly encroaching on their habitat. 

While agriculture, livestock breeding, forestry and human settlements are spreading towards the remaining lion habitats, the big predators are referred to isolated national parks and game reserves of limited extension. A healthy lion population however needs at least between 20 and 200 square kilometres of hunting grounds to sustain its number. 

In countries such as Cameroon, Mali and Senegal, lion populations further are not sufficiently mapped. German expert Hans Bauer told the journal 'Der Spiegel' there existed no long term studies of the lion populations in this region and estimates were based on "occasional visits". Bauer however does not protest the IUCN predictions as his own studies within the African Lion Working Group also pointed to low populations in Cameroon. 

The German scientist sees another problem in the little attention given West and Central Africa's lion populations. Even many conservationists did not consider the lion an endangered species and throughout the region, there existed "no scientific and protection programmes" targeting lions, Bauer complained. "Nothing is done," he adds.

Natural selection
New scientific research (made in East Africa) further shows that, when it comes to reproduction, the "natural selection" of female lions increases the males' burdens. Over generations, males with a big and dark mane have been preferred by their female counterparts - not the most humane criteria having Africa's baking sun in mind. 

US scientist Peyton West and Craig Packer discovered that males with a dark mane were preferred to blond males. Males with a big male were preferred to "topless" males. The scientists had let females choose between an ample selection of male dummies, and there were no doubts about their love taste, according to an article they published in the latest edition of 'Science'. Also other males treated those lions wearing a big, dark mane with respect.

It turned out that a big black mane was an indication of high testosterone levels and therefore a higher level of aggression. The unlucky males, however, are putting their health at risk. The mane significantly increases their body temperature, making them more liable to diseases. Might one therefore assume lions would exterminate by themselves within some thousand generations? 

Sources: Based on press reports, IUCN and afrol archives

 

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