Witnesses of a Mara River crossing, with its tension, fear and raw power, will agree that it’s one of the most incredible wildlife spectacles in the world. During a recent Tanzanian safari, Lee was able to find the perfect spot on the banks of the river for his guests to photograph the action as it unfolded right in front of them. Here’s his account of an epic trial of strength and survival, as the herds massed on the banks, preparing to leap into the terrifying waters.

High-pitched calls and bleats of the wildebeest increased in volume. The first intrepid animals made the plunge, opening the floodgates for the entire herd. A lioness, concealed until now, sprang into action and pulled down a young wildebeest. The herd faltered, regrouped and then flung itself into the river almost twenty feet below.

The instant that they hit the water, a huge crocodile cruised slowly upstream, towards an unfortunate straggler being swept down river. The wildebeest nearly made the safety of the far bank when the crocodile’s enormous head broke up through the surface of the water, gaping jaws snapping shut around the wildebeest’s haunches.

This monumental test of strength lasted three quarters of an hour, with the wildebeest gaining footing, only to be pulled back down by the crocodile, which was as long as the river banks were high and weighed close on a ton. If the river had been deeper at this particular spot, the crocodile would have drowned its victim swiftly, but in these shallows, the battle took much longer than usual for the reptile to win.