A swarm of bees has killed 63 endangered African penguins on a beach outside Cape Town, according to an AFP report .

The protected birds were found dead in a small town near Cape Town home to a colony of penguins, and post-mortems revealed that all the penguins had multiple bee stings. 

“After tests, we found bee stings around the penguins’ eyes,” the report cited David Roberts a veterinarian of Southern African Foundation for the Conservation of Coastal Birds (SANCCOB) as saying.

“There were also dead bees on the scene,” he told AFP by telephone.

“This is a very rare occurrence,” he added.

The area is a national park and the Cape honeybees are part of the ecosystem.

South African National Parks said samples had also been sent for disease and toxicology testing.

“There were no external physical injuries found on any of the birds,” a parks statement said.

Penguins cannot fly but they fulfil all the biological requirements to be classified as birds – they have feathers, they lay eggs and they're warm-blooded. There are also other flightless birds  like emus, ostriches and cassowaries.

SANCCOB said they would keep a "watchful eye" on the birds.

"Our rangers and SANParks will monitor the nests in the area as some of these birds would have had eggs and chicks," the organisation said in a statement on its social media.

"One partner often can't supply sufficient food or leave the chicks alone."

The organisation said numbers of the penguins were dwindling and the species could be extinct by 2035.

African penguins, which inhabit the coast and islands of southern Africa, are on the International Union for Conservation of Nature’s red list.

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