The Effect Poaching Has on the African Elephant Population

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output than females from intact groups.

Reproductive Skew of Male Elephants

Unlike females, male elephants never permanently join a new social group. They search for mates and sire offspring in diverse groups across the population. However, because female elephants are only sexually receptive a few days every 3-6 years (Poole & Moss 1989), sexually receptive female elephants are a scarce resource. Therefore, males compete for reproductive opportunities with other males in the population.

The intense elephant male competition has led to several behavioral, morphological and physiological traits that influence male dominance (Poole & Moss 2011). Males of different ages have diverse sizes. For example, a 20-year old male is 30% shorter than a 40 year old male. The older elephants are also twice the mass than the younger elephants (Poole 2011). The older larger males outrank the younger smaller males. The older males also have an added advantage because they show musth, a physiological state where males have elevated testosterone, aggression, and sexual activity (Poole & Moss 1981). The duration of musth increases with age, the older males are in musth for 2 or 3 months a year, while the younger males are in musth for a few days each year (Poole 2011). Therefore, regardless of size or age, the males with musth will outrank the males that are not in musth. In elephant communities, the age and musth status can strongly predict reproductive success. For example, in Samburu most offspring were sired by

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males in musth, and the oldest males sired the most offspring (Ishengoma 2008). The male elephant’s reproductive success increases with age.

Bearing in mind that age and musth status are the main predictions of reproductive success among male elephants, poaching creates a threat to the older male elephants because it tends to remove the older males from the population. The result of poaching may alter patterns of paternity in elephant populations (ARCHIE & CHIYO). When the older males are removed from the population, young males would increase the frequency and duration of their musth period (Slotow 2000). A comparison was conducted in three populations that experienced a rage of poaching; the results showed that reproductively dominant males are younger in poached populations. One argument is that poaching reduces the age of peak reproduction, which suggests that reproductive opportunities for younger males might increase, as a result decrease reproductive skew among males (Rasmussen 2008). However, a paternity analysis in poached populations does not side with this analysis. On the other hand poaching is said to increase male reproductive skew. A study done in Amboseli, shows that the three most successful male elephants sired 13% of all genotyped calves, while in Samburu, three of the top male elephants sired 19% and in Tarangire, there top most successful male elephants sired 23% of genotyped calves (Ishengoma 2008). Their demonstrates that poaching in turn increases male reproductive skew because poaching does not entirely eliminate all old males in a population. The few males that do remain in the population dominate reproduction (Ishengoma 2008). The reproductive tenure of the younger males is increased due to poaching. Therefore, based on the findings poaching increases the elephant male’s reproductive skew.

Because of the increase of male reproductive skew, this causes a problem of maintaining a genetic diversity in the elephant populations (ARCHIE & CHIYO). There is a big risk that there

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will be an increase of individuals that breed with close kin because the same population of males sires the majority of the offspring. If the number of breeding males reduces, this will decrease the effective population size of the elephant population and increase the loss of genetic diversity (ARCHIE & CHIYO). The evidence demonstrates that poaching indeed disrupts how elephants breed and causes great consequences for the long-term maintenance of the genetic diversity in elephant populations.

Conclusion

It is evident that poaching has adverse effects on the elephant population. It leads to stress in female elephants that affects their immunity, growth, reproduction and weakens their core groups. It also increases male reproductive skew causing important consequences for the long-term maintenance of genetic diversity in an elephant population. In addition to the above findings, according to The Nature Conservancy, elephants were once the most poached animals for their tusks. They go on further to report that there were 1.2 million elephants in Africa in 1980. Currently, there are only about 430,000 elephants left. Sadly, an estimated 30,000 elephants are being killed each year. However, not all human activity is negative. An article in the Newsweek Global featured a scientist called Richard Leakey, who is the head of the Kenya Wildlife Service (KWS) that has had successful efforts decreasing the rate of Elephant poaching drastically in the past. Unfortunately, the poaching of African elephants in Kenya has recently risen. To combat the recent poaching activities he started an online social media campaign "my elephants, my heritage" that was begun by Leakey and his protégé Paula Kahumbu. Other organizations have also taken different approaches to handle the problem of poaching. The World Wide Fund (WWF) tackles the problem of poaching by monitoring local sales and

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emphasizes on the ban. They work with the local people to develop alternative livelihoods, to reduce the demand for ivory. Their efforts have assisted in decreasing elephant poaching. However, there is still a large black market for elephant tusks used as luxury ornaments and objects in the Asian market. Therefore, WWF and other similar organizations are pushing governments to enforce anti-poaching laws, running patrols, and organizing campaigns for stronger action against the illegal wildlife trade.

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Work Cited

ARCHIE, E. A., & CHIYO, P. I. (2012). Elephant behaviour and conservation: social relationships, the effects of poaching, and genetic tools for management. Molecular Ecology, 21(3), 765-778. doi:10.1111/j.1365-294X.2011.05237.x

Douglas-Hamilton, Iain. "The Current Elephant Poaching Trend." Pachyderm, July 2008. Web. June 2009.

Dublin HT (1983) Cooperation and reproductive competition among female African elephants. In: Social behavior of female vertebrates (ed. Wasser SK). pp. 291 -313, Academic Press,