By Craig Welch
10 August 2016
(National Geographic) – The first fin whale appeared in Marmot Bay, where the sea curls a crooked finger around Alaska’s Kodiak Island. A biologist spied the calf drifting on its side, as if at play. Seawater flushed in and out of its open jaws. Spray washed over its slack pink tongue. Death, even the gruesome kind, is usually too familiar to spark alarm in the wild north. But late the next morning, the start of Memorial Day weekend, passengers aboard the ferry Kennicott spotted another whale bobbing nearby. Her blubber was thick. She looked healthy. But she was dead too.
Kathi Lefebvre is talking about the whales as we crunch across a windy, rocky beach, 200 miles north of Kodiak. In a typical year eight whales are found dead in the western Gulf of Alaska. But in 2015 at least a dozen popped up in June alone, their bodies so buoyant that gulls used them as fishing platforms. All summer the Pacific Ocean heaved rotting remains into rocky coves along the more than 1,000-mile stretch from Anchorage to the Aleutian Islands. Whole families of brown bears feasted on their carcasses.
Lefebvre, a research scientist at NOAA’s Northwest Fisheries Science Center in Seattle, Washington, had examined eye fluid from one of the carcasses in a failed attempt to winnow the cause of death. Now the two of us are on Kachemak Bay in Homer, Alaska, inching toward a wheezing, dying sea otter sprawled out on the shore. Otter deaths are skyrocketing on the shoreline beneath the snowcapped Kenai Mountains, so Lefebvre is here to see whether the fates of these otters and whales are somehow intertwined.
In the past few years death had become a bigger part of life in the ocean off North America’s West Coast. Millions of sea stars melted away in tide pools from Santa Barbara, California, to Sitka, Alaska, their bodies dissolving, their arms breaking free and wandering off. Hundreds of thousands of ocean-feeding seabirds tumbled dead onto beaches. Twenty times more sea lions than average starved in California. I watched scientists lift sea otter carcasses onto orange sleds as they perished in Homer—79 turned up dead there in one month. By year’s end, whale deaths in the western Gulf of Alaska would hit a staggering 45. Mass fatalities can be as elemental in nature as wildfire in a lodgepole pine forest, whipping through quickly, killing off the weak and clearing the way for rebirth. But these mysterious casualties all shared one thing: They overlapped with a period when West Coast ocean waters were blowing past modern temperature records.
As hotter oceans destroy coral reefs in the tropics and melting ice alters life in the Arctic, it’s been easy to overlook how much warm water can reshape temperate seas. No more. Between 2013 and earlier this year, some West Coast waters grew so astonishingly hot that the marine world experienced unprecedented upheaval. Animals showed up in places they’d never been. A toxic bloom of algae, the biggest of its kind on record, shut down California’s crab industry for months. Key portions of the food web crashed. It’s not clear if greenhouse gas emissions exacerbated this ocean heat wave or if the event simply represented an outer edge of natural weather and climate patterns. But the phenomenon left daunting questions: Was this a quirk, an unlikely confluence of extremes that conspired to make life harsh for some sea creatures? Or was it, as one scientist says, a “dress rehearsal”—a preview, perhaps, of what hotter seas may one day bring as climate change unleashes its fever in the Pacific?
While Lefebvre and I are pondering our next move, a radio call comes in. Another dead otter has surfaced on Homer Spit, five miles away. We retrace our steps to a dusty parking lot, pile into a pickup, and head off. [more]