Investigation probes causes of mass pelican deaths from avian flu in Greece
Scientists have released key findings into the 2022 avian influenza outbreak that killed more than 2,300 Dalmatian pelicans in Greece, devastating the world’s largest breeding colony at Lake Mikri Prespa. The outbreak wiped out around 60% of the colony, marking the worst wildlife die-off ever recorded in the country.
Researchers found that the pelicans were likely infected through contact with droppings from other waterbirds, such as ducks and geese, which carried the virus without showing symptoms. The virus appears to have spread during winter, when unusually large numbers of migratory birds used the pelicans’ nesting islets. Notably, Great White Pelicans nesting nearby were not affected.
Accordign to Natasha Karathanou's article for AMNA, the outbreak in spring 2022 killed more than 40% of southeastern Europe’s breeding population of the species—about 10% of the global total. While western Greek colonies were largely spared, eastern inland colonies, particularly Prespa, suffered heavy losses. Scientists suggest colder temperatures and freshwater conditions favored the virus’s spread.
Encouragingly, later monitoring detected antibodies in some chicks, indicating that a small number of adult pelicans survived and developed immunity. However, experts warn that the virus continues to mutate, and new, more dangerous strains cannot be ruled out.
Due to the pelicans’ slow reproduction rate, scientists say it could take decades for the Prespa colony to recover fully, especially as additional threats such as drought and predation further strain the population.
