Millions of years ago lions flourished all over the world, but now are cornered into small parts of Africa. African lions are currently estimated at inhabiting 22% of their historical range, and 77% of their current range resides in southern and eastern Africa (12). Habitat loss from agriculture and human expansion is causing metapopulations to form within the lion community. Specifically throughout Western Africa, lions are declining in some protected areas, and have virtually disappeared from non-protected areas, except in Chad and the Central African Republic. These findings have made the Panthera leo unofficially endangered in certain regional areas of Africa (4). Habitat fragmentation makes the lions more vulnerable to extinction because confinement makes them less resistant to disease, climatic change, and devastating events. The formation of metapopulations throughout the continent has also led to inbreeding. The probability of mating with an individual with similar genetic material greatly increases with small populations, and thus, creates a more genetically similar population. In the case of the Panthera leo species, inbreeding is evident in many countries including South Africa (8). With inbreeding, lions will lose genetic diversity in the population, and will therefore also be more susceptible to dying off from disease, environmental catastrophies, and other events because of genetic similarity. Both confinement and inbreeding from habitat loss have made the African lion very vulnerable to extinction. The extent of habit loss can be seen in the map below as there are only a few protected areas for lions, and the species is now rarely found outside protected lands for most countries in Africa (4).
Climate Change
Rising global temperatures and more severe weather patterns are causing imbalance in ecological food webs, increasing susceptibility to novel disease, and are making lions resort to moving to alternative environments like agricultural areas. A large amount of the lion species may be vulnerable to life-threatening diseases in the future. Past extreme weather conditions have shown an increase in hemoparasitism (parasites in the blood), ticks, and viral as well as bacterial infections in lions (16). The extreme drought followed by heavy rains makes favorable environments for these infectious agents to invade the lion hosts. Another cause for concern from global warming is based on the alteration of the food web. A lions diet can consist of many other animals including: giraffe, wildebeest, buffalo, zebra, warthog, and kudu (18). With severe drought, the prey of lions may be affected from there being less primary producers and consumers to feed upon, which can in turn impact lion populations. Global temperatures are supposed to rise 2-6 degrees Celsius in the next 100 years, so we need to make a concerted effort to watch the effects on the ecosystem level. Studies have shown that the effects of climate change can be evident, as lions will have decreased mane lengths (14). The decrease in mane length from climate change may affect courtship and reproduction in lions as males will have an altered physical appearance. The image below is a representation of the amount of possible hair loss for African lions (14).
Potential Effect of Global Warming on Lion Mane Formation |
African lions have been known to frequent agricultural lands for feeding, and exploitation of these areas could increase even more with rising global temperatures. Ranchers combat lions by killing them to protect livestock. In conjunction with global warming, increased lion attacks on farms in Kenya have shown to be correlated with low precipitation during droughts (13). The killing of lions from stock raiding of cattle may seem awful, but farmers are estimated to have lost $290 per year in Kenya and $370 per year in Cameroon. These numbers may not seem like a lot, but in Cameroon alone, stock raiding by lions results in financial loses of up to 22% (12). The ranchers can’t afford to lose their livestock, and the starving families in Africa can’t afford to lose more food. The ethical debate remains whether the killing of African Lions raiding agricultural lands is a just form of defense.
The Sad Reality of Lion Poaching to Protect Livestock in an African Village |
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