A sea lion slumps on its back, belly and neck exposed. A wildlife worker swabs another’s nose; curled into a comma, the emaciated animal screeches in protest. In another shot of Reuters B-roll, humans in hazmat suits shovel a shoreline grave under colorless skies, sprinkling a red mass of carcasses with chemical powder before sealing the burial with dark wet sand.
The numbers are as bleak as the footage: More than 3,400 sea lions sickened and dead of the H5N1 variant of avian influenza in Peru this winter and spring. With the animal weighing, on average, about 770 pounds, each of those infected corpses threatens to further pulse the pathogen along the Peruvian coastline, according to researchers there.
Scenes this stark are harder to ignore than slower forms of species demise quietly spread out over time and space: Here is a riverbank littered with lifeless mussel shells, the plains where 200,000 antelope dropped dead, corals stripped of sea urchins, a continent across which bush fires killed or displaced three billion animals. Die-offs like these jolt us even as tens of thousands of species steadily twinkle off into extinction in the Anthropocene. “They really feel biblical in their proportions,” Sam Fey, an associate professor of biology at Reed College, told me.
Their scale—that of carnage—seems to speak to our modern ecological anxiety, rage, and grief; mass mortality events are material evidence of anthropogenic apocalypse, an unignorable and immediate tally of the ravages we’ve sown. And they will likely become more common as heat waves, droughts, disease outbreaks, storms, fires, and other environmental disturbances grow more frequent and deadlier. News coverage of die-offs, however, fails to acknowledge all we don’t understand about mass death. In reality, we’re nowhere close to grasping the repercussions these cascades of death have on ecosystems. “We’re still a far way away from having a firm view,” Fey said. “As a field we know very little about these events.”