Highly pathogenic avian influenza has been confirmed in seven northern elephant seal pups in Santa Cruz, California, marking the first occurrence of the virus in these marine mammals.
In a concerning development, the University of California, Davis, reported that seven northern elephant seal pups in the Año Nuevo State Park, located in Santa Cruz, California, tested positive for highly pathogenic avian influenza (HPAI). This marks the first instance of avian influenza being detected in northern elephant seals, a species known for breeding in this region, where approximately 5,000 seals gather annually for birth and breeding. The positive cases were identified among about 30 seal pups that recently died, with the presence of abnormal respiratory symptoms, weakness, and tremors observed among the affected seals, raising alarm regarding the potential spread of the virus in the seal population.
The outbreak of HPAI in elephant seals follows a tragic incident reported in Patagonia, Argentina, where an estimated 17,400 seal pups perished, representing about 90% of the pups born during the breeding season. Additionally, reports emerged of adult female seals dying near South Georgia Island around the same time, but until now, there had been no detected cases of the avian virus among the northern hemisphere's breeding northern elephant seals along the U.S. and Mexican coast. This recent detection raises concerns about the health of the populations in these areas and highlights the vulnerabilities of marine mammal species to avian influenza, a disease typically associated with birds.
Experts, including Roksan Beltran from UC Santa Cruz, noted that despite the alarming findings, the majority of the seal population remains healthy, as most adult female seals had weaned their pups and left the beach prior to the outbreak. However, approximately 1,350 seals still remain on the beach, and new cases of affected pups have been reported, with around five pups per day falling sick or dying. This situation poses a significant risk not only to the elephant seals themselves but also serves as a potential indication of broader environmental and wildlife health issues, prompting further research and monitoring into the potential spread of HPAI among marine wildlife.
