We saved gray whales from extinction. Why are so many dying again?

March 11, 2026·13 min·1 clip

Gray whales recovered from near-extinction, but hundreds started washing up dead again in 2019—why?

The episode opens with host Regina Barber introducing the gray whale story alongside marine ecologist Joshua Stewart from Oregon State University. Stewart traces the history of industrial whaling, which killed roughly 3 million whales over 70 years and reduced some gray whale populations to just 5 percent of historic numbers. Whaling stopped primarily because populations had been reduced so far it was no longer economically viable. The modern conservation movement was partly sparked by Roger Payne's 1970s vinyl record of whale songs, which shifted public sentiment. An international moratorium on whaling was implemented in the 1980s and gray whales recovered so successfully they were removed from the endangered species list in 1994. Then in 1999 hundreds of whales began washing up dead along the west coasts of the US, Canada, and Mexico. Scientists estimated thousands more died at sea during the animals' 10,000-mile round-trip Arctic migrations, accounting for roughly a quarter of the population. The same pattern occurred in 2000, then stopped and the population recovered, and then happened again starting in 2019. Stewart became part of a government-convened expert team investigating the new die-offs. The team discovered the population had been going through boom-and-bust cycles before 1999 as well, including a major decline in the 1980s. An email from Arctic scientist Jackie Grebmeyer provided the key breakthrough: her decades of data on benthic crustaceans in Arctic seafloor sediments aligned perfectly with the gray whale population cycles. Stewart explains that all of the whales' annual energy comes from these crustaceans consumed during a three-to-five month Arctic feeding window. Once a population reaches carrying capacity and food competition is fierce, even small fluctuations in food availability cause dramatic die-offs. This is unusual for long-lived animals that take decades to reach sexual maturity and reproduce slowly. While previous cycles recovered within a few years, the 2019 die-off has continued with birth rates remaining at rock bottom, a pattern Stewart attributes to climate change reducing average plankton availability in Arctic ecosystems. He describes gray whales as a climate alarm bell and a canary in the coal mine for ocean ecosystem health.

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