Each year 1.2 million wildebeest migrate from Tanzania into Kenya where they repeatedly cross the Mara River. During these iconic river crossings, wildebeest drown by the hundreds to thousands. In a paper appearing this week in the Proceedings of the National Academy of Sciences, Amanda Subalusky, Chris Dutton, Emma Rosi, and David Post quantify the number of wildebeest drowning and track the fate of wildebeest carcasses.
Subalusky et al. (2017) estimates that 6250 carcasses and 1100 tons of biomass enter the Mara River each year from the mass drowning events. The carcasses feed crocodiles, vultures, and the aquatic food web as they decompose. Bones from the carcasses provide a long-term source of phosphorus for aquatic producers and consumers.
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