Portland, Maine – Avian influenza is wreaking havoc on seals and sea lions globally, leading to widespread deaths and presenting challenges for scientists seeking to contain the virus’s devastating effects.
The outbreak, which originated in 2020, has decimated millions of domesticated birds and has now spread to wildlife populations worldwide. While experts believe the virus poses a minimal risk to humans, its impact on both agricultural operations and natural ecosystems has been severe, causing economic disruption and environmental imbalances.
Seals and sea lions in locations as distant as Maine and Chile are experiencing heightened vulnerability to the disease. Cases have been reported in seals along both the east and west coasts of the U.S., resulting in the deaths of over 300 seals in New England and several more in Washington’s Puget Sound. The situation is particularly dire in South America, where tens of thousands of sea lions in Chile and Peru, as well as numerous elephant seals in Argentina, have succumbed to the virus.
Marcela Uhart, director of the Latin America program at the University of California, Davis, expressed concern over the virus’s impact on wildlife, emphasizing that once it enters wild populations, its rapid transmission can devastate vulnerable species. The lack of prior exposure leaves marine mammals like South American seals susceptible to the virus, leading to alarming mortality rates.
Researchers are still investigating how seals contract the bird flu, but it is believed to be primarily from contact with infected seabirds. The consequences have been significant, with high mortality rates among South American marine mammals and seabirds in Peru and Chile numbering in the hundreds of thousands since the virus emergence in late 2022.
Aside from South America, the virus has now reached mainland Antarctica for the first time, underscoring its pervasive and relentless spread. The consequences of seal and sea lion deaths extend beyond animal populations, affecting the delicate balance of marine ecosystems where these creatures play vital roles in maintaining biodiversity.
Concerns are also raised about the virus spreading to more endangered species, as highlighted by the potential role of bird flu in the deaths of endangered Caspian seals in Russia. The World Organisation for Animal Health has warned of the unprecedented risk of wildlife population collapse due to the scale of the current wildlife losses.
In the U.S., a significant outbreak of bird flu in harbor and gray seals along the North Atlantic coast in 2022 has prompted researchers at Tufts University to investigate further. The seal die-off, attributed to bird flu by the government, underscores the need for vigilance and preventive measures to avoid potential repeat incidents.
Scientists and environmental advocates are exploring possible links between the outbreaks and climate change, with warmer sea temperatures affecting forage fish populations and making marine mammals more susceptible to disease. Vaccinating poultry and avoiding contact with potentially infected wildlife are cited as crucial steps in curbing the spread of the virus and safeguarding vulnerable populations.
As the avian influenza virus continues to mutate, posing threats to both wildlife and humans, active surveillance and management are deemed essential to preventing further outbreaks. The interconnectedness of various species in these multispecies outbreaks underscores the urgent need for measures to limit spillover and protect ecosystems.
The potential consequences of further seal deaths on global ecosystems are a cause for concern, prompting calls for continued monitoring and conservation efforts to mitigate the impact of the ongoing avian influenza crisis.