Male lives matter. Old bull elephants sire more offspring than younger studs. However, it’s not just the females who find ‘sugar-daddies’ irresistible; trophy hunters and ivory poachers target the oldest, most well-endowed, bulls. The bigger the tusks adorning a hunter’s pad, the more they will impress his guests on the dinner-party circuit back home.
Botswana has around 130,000 elephants, more than any other African country. It will allow 400 tusks to be exported this year. Hunting, the politicians claim, is necessary to ‘control’ numbers and protect farm livelihoods. It is also a lucrative business. King Juan Carlos was ‘found out’ when injured during an elephant safari in Botswana. Donald Trump Jr is another enthusiast.
Targeting big males, trophy hunters claim, has no significant impact on elephant numbers and gives young bucks a chance to breed. The authors of a paper just published disagree.
Elephant society is hierarchical. Youngsters, of both sexes, live in herds with their mother, grandmothers, and aunties. These elephant-caravans, led by a matriarch, travel widely in search of food water, and, occasionally, salt. Between the ages of 10 and 20, young males leave their natal herds and join all-male ones. These bachelor herds have received less attention from scientists than the natal ones.
Conny Allen, of Exeter University, wants to address this imbalance. His team set up camera traps along seven traditional pathways in Botswana’s Makgadikgadi Pans to monitor elephant traffic.
Footage, recorded between October 2017 and September 2018, shows that adolescent elephants tend not to travel alone. The reason, the researchers think, is that ‘lone travel is riskier for younger, newly independent and less experienced, individuals’. Lions, whose hunting success-rate in Botswana’s Savute region is about 50%, target mostly adolescent ones. Lone animals also fall victim to hunters; human activity is the leading cause of elephant mortality in most populations.
Leadership by mature adult bulls did not vary between wet and dry seasons, ‘suggesting that mature bulls play a key role in the all-male elephant society, regardless of season’. The group’s leader, a mature individual, walks in front of the group. Guiding, however, is not his only function.
The ‘grandmother hypothesis’ explains why women undergo menopause. Older people, with a lifetime of experience behind them, are human filing cabinets, reservoirs of wisdom, valuable in difficult times. Granny may remember what the herd did during the last drought flood or pandemic. By helping her daughters instead of having more babies, Granny’s ‘genetic dividend’ is increased. The benefits, the offspring gain from her guidance, outweigh the resources a matriarch consumes.
Elephant grannies, unlike human ones, don’t cease to be fertile, but their rich experience is invaluable in the trials and tribulations their grandchildren will have to face. Likewise, old bulls educate younger males in the bachelor herds. When trophy hunters kill them, a vital resource is lost.
The idea isn’t new. I remember a Zulu guide, in Hluhluwe-Imfolozi many years ago, describing how the old bulls there had been killed by hunters. Large males had to be imported to put manners on ‘bolshie’ young tuskers who had taken to attacking rhinos.
Importance of old bulls: leaders and followers in collective movements of all-male groups in African savannah elephants. Scientific Reports. 2020.