Annual mass drownings of the Serengeti wildebeest migration influence nutrient cycling and storage in the Mara River

• Published in: Proceedings of the National Academy of Sciences
• Main Authors: Subalusky, Amanda L., Dutton, Christopher L., Rosi, Emma J., Post, David M.
• Format: Text
• Language: English
• Published: National Academy of Sciences 2017
• Subjects: Biological Sciences; Mara; Mara River; Blue whale
• Online Access: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5530641/; http://www.ncbi.nlm.nih.gov/pubmed/28630330; https://doi.org/10.1073/pnas.1614778114

Much research has focused on the influence of animal migrations on terrestrial ecosystems. Mass drownings are an understudied phenomenon associated with migrations that may have substantial impacts on aquatic ecosystems. Here, we show that mass drownings of wildebeest occur nearly annually during the Serengeti wildebeest migration, and these mass drownings contribute the equivalent biomass of 10 blue whale carcasses per year to this moderately sized river. Soft tissues of the carcass decompose within several weeks and are assimilated by both in-stream and terrestrial consumers. Bones decompose over years, which may influence nutrient cycling and food webs in the river on decadal time scales. The loss of migrations and associated mass drownings may fundamentally alter river ecosystems in ways previously unrecognized.