A growing number of zoos are reporting animal deaths due to bird flu, with potentially “grave implications” for endangered species. The highly pathogenic avian influenza (HPAIV) virus is spreading among wild birds and can also infect captive animals in zoos.
Several cases have been reported in the US, including a cheetah, mountain lion, Indian goose, and kookaburra at Wildlife World Zoo near Phoenix. The San Francisco Zoo temporarily closed its aviaries after a wild red-shouldered hawk was found dead with HPAIV. A rare red-breasted goose died at Woodland Park Zoo in Seattle, causing the zoo’s aviaries to close.
Researchers warn that infected wild birds can spread the virus among captive animals through bird flight and contact. This is more likely to happen during migration seasons. The US has seen a rise in bird flu cases, especially in geese and waterfowl, with a “sharp jump” in Iowa.
To manage this situation, zoos are considering enhanced biosecurity measures or vaccinations for zoo animals. Researchers have warned that HPAIV can kill primates, rodents, pigs, and rabbits, as well as some endangered species like tigers and clouded leopards.
Zoos take various approaches to biosecurity, which can affect their vulnerability to the virus. Experts emphasize the importance of limiting access for wild birds to enclosures and implementing measures to reduce the risk of infection for endangered animals.
The spread of bird flu viruses is not limited to zoos; it also affects dairy farms and wildlife. In California, nearly half of the state’s dairy farms have been affected by the virus, with two farm workers testing positive. In Los Angeles, two indoor cats are suspected to have died after drinking infected raw milk.
While some regions, such as the UK and EU, have licensed bird flu vaccines for use on captive zoo animals, this is not allowed in the US. Experts stress that zoos should take additional hygiene precautions to prevent the spread of HPAIV among their animals.
Source: https://www.theguardian.com/environment/2024/dec/19/bird-flu-zoos-endangered-animals-captive-species-lions-tigers-cheetahs-virus