At least 50 hippos and several other large animals have died from an anthrax outbreak in eastern Congo’s Virunga National Park, according to park officials. The carcasses were seen floating in the Ishasha River, which flows into Lake Edward—one of Africa’s major lakes.
Virunga Park Director Emmanuel De Merode confirmed on Tuesday that tests had identified anthrax as the cause of death. Buffalo are also among the animals affected, though the exact source of the contamination remains unclear.
Images shared by the park show lifeless hippos lying on their sides and backs, either drifting in the river or lodged along its muddy banks.
The deaths mark a significant setback for conservation efforts. Virunga has worked for years to restore its hippo population, which plummeted from over 20,000 in the 1970s to just a few hundred by 2006 due to conflict and poaching. The population had since recovered to around 1,200.
Park rangers first noticed the die-off about five days ago, when bodies began surfacing in a stretch of the river near the Congo-Uganda border, a region currently under the control of rebel groups.
Anthrax, a deadly disease caused by bacteria naturally present in soil, can infect wildlife through inhalation or ingestion of contaminated soil, plants, or water.
The Congolese Institute for Nature Conservation issued a public warning on Tuesday urging local communities to avoid contact with wildlife and to boil drinking water drawn from local sources.
A response team has been dispatched to the area, but De Merode said efforts to remove and bury the carcasses have been hampered by difficult terrain and limited equipment.
“We’re trying to extract and bury them using caustic soda, but we don’t have excavators, and access is extremely challenging,” De Merode told Reuters.
The river flows north into Lake Edward, where additional hippo carcasses have been reported.
“There are more than 25 dead hippos floating between Kagezi and Nyakakoma,” said Thomas Kambale, a civil society leader in the lakeside town of Nyakakoma.
Virunga National Park, a UNESCO World Heritage site, is home to an extraordinary range of biodiversity, including more species of birds, reptiles, and mammals than any other protected area in the world. However, it has long been threatened by conflict, with militia groups operating in and around the park since the region’s civil wars in the early 2000s.