Friday, November 2, 2012

The role of older males in elephant society

Last time I wrote about the importance of older females in societies such as those of humans, killer whales and elephants. I didn’t want to leave out grandpas so this time I’ll cover the importance of older males, specifically in elephant society. This is interesting as older males seem to fulfill a very different role to older females in elephant populations. 

Among elephants, males lead vastly different social lives to females. The females stay in their matriarchal groups throughout their lives. These groups are led by the oldest female and consist of related individuals which often form associations with other female groups. Upon reaching sexual maturity at around 11 to 16 years of age males usually leave the female herd to go and live alone or join a bachelor herd. During this time they will start to go into musth, a state of heightened testosterone that males go into every year. During this time males have one thing on their mind: females! And anything that gets in the way of their quest for females can feel the brunt of all this extra testosterone. 
During musth males secrete from their temporal gland, behind the eye.

This is when the old timers are rather important. Older bulls are more dominant than younger bulls. Because of this they suppress the musth of younger males, meaning it either does not occur at all or is reduced in strength and length of time. This slow introduction to musth is a necessary part of development in young males. When young males do not have older bulls around to keep them in check their behavior can get out of control. This was witnessed in Pilanesberg National Park in South Africa where a number of young bulls were released as orphans and without an older role model to quell their aggression many of them became extremely dangerous. In fact 40 rhino were killed in 4 years by these young males as well as a number of cars being tipped over. However after older bulls were translocated to the park the killing and destruction stopped. 

It is clear that, just like the grannies of elephant family units, the older males fulfill an important niche in elephant society. They keep those young boys under control, reduce conflict and allow for a steady introduction to musth and adult life. Unfortunately these old males are also the elephants with the biggest tusks, and are therefore the most sought after by poachers. This human selection of big males could have a significant impact on elephant society, as seen by the example in Pilanesberg. And thus we have yet another reason why we should do as much as possible to protect these magnificent animals (not that we needed any more!). 

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