Huge die-offs of elephant seals occurred after the virus gained nearly 20 troublesome new mutations, scientists found. Huge die-offs of elephant seals occurred after the virus gained nearly 20 troublesome new mutations, scientists found. your-feed-science, Mammals, Avian Influenza, Cattle, Birds, Viruses, Wildlife Die-Offs, Seals (Animals) and Sealing, Livestock, Argentina, Brazil, Chile, Latin America, Patagonia (Argentina), Peru, South America NYT > Science