Monday, August 17, 2015

Good Gnus, the Migration is Coming!

The great migration of wildebeests in East Africa refers to the annual movement of their herd, numbering over one million individuals, from the Serengeti to the Masai Mara, and back. Their migration seems to follow the rainfall so that grass and drinking water are always abundant for the wildebeests. When the migration comes, we have the distinct pleasure of being able to watch tens of thousands of wildebeests, or gnus, cross the Mara River at a given time.

Apart from the breathtaking sight which I described above, the migration also makes for one of the most exciting and challenging times of the year for fisi camp researchers. Most of the observational data we collect involve interactions and aggressions between hyenas within our study clans. We see these interactions on a daily basis, however they become significantly more frequent and intense at carcass sessions. These sessions are extremely important, but can also be very overwhelming; imagine trying to identify and keep track of thirty hyenas who are congregating around a carcass, standing in front of each other, changing places, and blocking your view. All the while, you're also charged with catching any and all interactions between the hyenas present to make the most of the session. And if you happen to come across a session like this while the sun is up, consider yourself lucky!

When there's food to compete over, the state of the hierarchy really becomes clear as the higher ranking hyenas aggress on the lower ranking hyenas to keep them away from the carcass, providing us with tons of valuable data. For this reason, when there is a change in the hierarchy, a rare but exciting occurrence, we're most likely to notice it at a carcass session. When the wildebeests come, the abundance of prey for hyenas and other large carnivores in the Mara increases tremendously. This means more hectic sessions, and in turn, more useful data.

So, as the migration closes in on us in Serena, we're looking forward to the annual grass trimming provided by the wildebeests, and the crazy months ahead!

No comments:

Michigan State University | College of Natural Science