The wildebeest, thundering across the plains in giant herds, has an uncanny ability to sense rainfall and the promise of new grass, enabling them to survive in Africa's dryest areas. According to an article in Smithsonian magazine, the shaggy animals that cross thousands of miles each year chasing the rains might be in danger of population losses despite their keen senses.

The wildebeests migrate from the Serengeti grasslands through Tanzania and into southern Kenya each year in search of water and grass during the dry season. The article quotes photographer Suzi Eszterhas, who has lived among the wildebeests to document their migration, marvelling, "The sky is empty except for one faraway rain cloud and — boom — within an hour they're off in a mass ... moving as one, all heading for that single cloud."

According to the article, the wildebeests are active shapers of their ecosystems while they migrate in this manner. They "crop grass and fertilize land with their droppings," and serve as protein for the predators who follow them along the way. And that's the problem at the moment. More and more of the wildebeests are perishing along their journey, drowning in the Mara River or falling prey to crocodiles.

The Smithsonian writes that the river has been unusually high for the past three years, citing deforestation as a main cause. Eszterhas watched nearly 5,000 wildebeests die trying to cross the river's deadly currents. These deaths come in addition to poaching by humans and "intense variations in seasonal flooding and drought" due in part to climate change. The article cites scientists who are disturbed to think that the "Serengeti's keystone species" might be threatened by such altered conditions.

For further reading: For wildebeests, danger ahead