An epidemic of avian flu in Patagonia appears to be on the decline after decimating southern elephant seal populations for the last year and half, with researchers finding no new cases in recent surveys of the coast. But the recovery process for many colonies, which were nearly wiped out in some areas, could be just beginning. The H5N1 influenza hit populations of southern elephant seals (Mirounga leonina) and other marine mammals and birds in August 2023, spreading across multiple provinces of Argentinian Patagonia and sending researchers scrambling to study the outbreak. With cases now on the decline, researchers are turning their attention to studying the worst-hit colonies as they recover their previous population numbers, a process that could take decades. “There were no mortality events from avian flu” observed during the recent surveys in the province of Chubut, said Valeria Falabella, the director of coastal-marine conservation at the NGO Wildlife Conservation Society (WCS) Argentina. “The not-so-good news is that the number of individuals, most notably reproductive females, was way below what was expected.” The 300-kilometer (186-mile) coastline of the Valdés Peninsula, a popular breeding area for southern elephant seals, saw 17,400 of the 18,000 pups die at the end of last year, according to a December 2023 study in Marine Mammal Science. Usually only approximately 180 die. The study described the spiking mortality rate as “catastrophic.” The flu likely jumped to marine mammals in the area from South American terns (Sterna hirundinacea), mostly affecting elephant seals but also spreading to…This article was originally published on Mongabay
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South Africa Today – Environment
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