In her three decades of working with elephant seals, Dr. Marcela Uhart had never seen anything like the scene on the beaches of Argentina’s Valdés Peninsula last October.
It was peak breeding season; the beach should have been teeming with harems of fertile females and enormous males battling one another for dominance. Instead, it was “just carcass upon carcass upon carcass,” recalled Dr. Uhart, who directs the Latin American wildlife…