An outbreak of avian influenza, which began in 2020, has been wreaking havoc on seals and sea lions across the globe, leading to the deaths of tens of thousands of marine mammals. The virus, which has already caused the deaths of millions of domesticated birds, has now spread to wildlife populations worldwide, causing economic turmoil and environmental disruptions.
Seals and sea lions in various regions, from Maine to Chile, have been particularly vulnerable to the disease. In the U.S., the virus has been detected in seals on both the east and west coasts, resulting in the deaths of over 300 seals in New England and a smaller number in Puget Sound, Washington. The situation is even more dire in South America, where more than 20,000 sea lions and thousands of elephant seals have succumbed to the virus in Chile, Peru, and Argentina.
Scientists are still investigating how the seals have contracted the bird flu, but it is believed to be through contact with infected seabirds. The virus has caused high mortality rates among South American marine mammals since its arrival in late 2022, with hundreds of thousands of birds in Peru and Chile also perishing from the virus.
The spread of the virus has now reached mainland Antarctica for the first time, posing a significant threat to wildlife populations in the region. The deaths of seals and sea lions disrupt ecosystems where these marine mammals play crucial roles as top predators, helping to maintain balance in the ocean by controlling fish populations.
Concerns have been raised about the potential for the virus to jump to more endangered species, such as the Caspian seals in Russia, which may have been impacted by bird flu in the past. The World Organisation for Animal Health has warned that the current scale of wildlife loss poses a significant risk of population collapse, creating an ecological crisis.
Researchers have also suggested a possible link between the outbreaks and climate change, with warming oceans affecting the food supply of marine mammals like sea lions. Vaccinating poultry and avoiding contact with potentially infected animals in the wild have been recommended as preventive measures to curb the spread of the disease.
Even seals in aquariums are not immune to the threat of bird flu, prompting facilities like the New England Aquarium to implement strict sanitation protocols to protect their animals. The mutations of the avian virus have raised concerns about its potential impact on other species, including humans, emphasizing the need for active surveillance and management of outbreaks.
The continued deaths of marine mammals could have far-reaching consequences on critical ecosystems worldwide, underscoring the importance of addressing the spread of avian influenza to safeguard biodiversity and ecological balance.