Spotlight Africa: Simple questions about Amboseli’s elephants, complex answers
Recently, I met up with Steve Njumbi, Head of Programmes at the International Fund for Animal Welfare. Steve was trained down in Amboseli some years ago, before embarking on elephant studies of his own, so we spent a while catching up on elephant news.
He asked me if I felt that the Amboseli elephant families were disrupted, which is a very fair question, given this is the point of our study. My first reaction was that the elephants weren’t showing behavioural signs of disruption; after all they don’t spend every moment vigilant and terrified to the point of running away, like my study elephants in Republic of Congo.
On further reflection, however, I think I have to revise my answer.
After all, there’s a very big difference between habituation (animals that are used to being around people, or certain groups of people in certain situations) and the kind of chronic stress that might be classified as disruption, which can affect an individual’s welfare and reproductive ability and therefore, ultimately, the success or failure of wild populations.
This kind of disruption is a far more subtle process, requiring intimate knowledge of what is “normal” in a population, and this is exactly why we’re doing this work in Amboseli.
One of the fascinating, and frustrating, things about elephants is that there are rarely easy, straightforward answers. For almost everything that is “measurable” about elephants in a scientific sense – all the “How big?” “How far?” “How much?” “How often?” questions – the answer varies hugely, largely depending on “who” and “when”.
It shouldn’t really be a surprise that such long-lived, highly social animals are flexible and adaptable; but it does make it hard to give simple answers to simple questions.
Elephant behavioural cycles change over time, responding to the availability of food and the presence of pressures or threats, such as changing land use and security.
During the late 1980s when poaching threats in Amboseli were high, elephants were “compressed” inside the security of the Park, and were found in larger groups. Over the 40-year span of the Amboseli Elephant Research Project, we have documented social changes and shifts that happen over the course of decades. A major factor in this has been the size of the family – as family units have become larger, the amount of time the family spends all together, and the amount of time they spend associating with other elephant families have both decreased.
After just one year here, it’s hard for me to say what is “normal” for Amboseli elephants. However my best answer for Steve and you is that they’re still recovering and that this year has been an exceptional one.
The first rains of the year ceased abruptly, shortly after my March post. During the dry period that followed, elephants did not break up into smaller groups as quickly as we expected, and were still in large groups of 100 elephants or more right into May.
Amongst the elephant researchers who work here, Amboseli is famous for the “August vacations” when all the families disperse over the ecosystem, and there’s barely an elephant to be found inside the Park boundaries. Preparing myself for long days driving and searching for elephants, I was also looking on the positive side – plenty of reasons to stay in camp and catch up on reports, papers and all the other things that I slip away from in order to spend precious time in the field. Except the “vacations” didn’t happen this year, as every family continued to spend time in or around the Park’s swamps.
Towards the end of the dry season, I was constantly surprised by the groups I found. The elephant groups had become smaller as the dry season progressed, but in these small groups there were often members of several different families together.
When I checked the long-term records, and discussed my field time with colleagues, I discovered that some of these combinations hadn’t been seen together for years. Some elephant families actively dislike each other, and will avoid each other or have negative interactions when they do meet. It seems after the death of the females involved in such “feuds”, younger family members are quite willing to re-establish their relationships.
How all these changes work out in the medium to long term, and what it means for the families and their social relationships, it’s still too early to say.
Now the rains are here again, a huge relief for all the people and wildlife in the Amboseli ecosystem.
We have a “baby boom” starting too and this combination of events has resulted in the elephant families getting together in large groups again. Small calves are very attractive to all elephants, and as a rare commodity at the moment, they are at the centre of a lot of interactions both between- and within- families.
We know from previous studies in Amboseli that experienced matriarchs are better at accurately detecting and responding appropriately to threatening situations (such as lions). My work is much more focused on the day-to-day decisions about where to go, what to eat, who to spend time with, which ultimately affect the health and reproductive success of individuals.
As fresh grass grows across the south and east of the park, even families that normally inhabit the extreme west of the ecosystem are to be found in large groups, moving through the woodlands in this area. We still see of lot of mixing of families, and it may be that the old experienced matriarchs are attractive to elephant families who don’t have an experienced female leader.
Much of my field time at the moment is working around groups of several hundred elephants, trying to see who is following whom, and how much “exploitation” of these experienced matriarchs is happening. It’s very confusing sometimes, but also wonderful to see lots of leadership behaviour, and interactions that I can use to work out the friendships between families.
Part of me thinks that, as a trained elephant researcher, Steve should have known better to ask such a simple question and expect a simple answer! However, I hope that he agrees with me that the complex truth is far more interesting.