SEATTLE — Researchers say the population of gray whales off the West Coast of the United States has fallen by nearly one-quarter since 2016, resembling a similar die-off two decades ago.
NOAA Fisheries reported Tuesday that surveys counted about 6,000 fewer migrating whales last winter, 21,000 as compared with 27,000 in 2016.
The agency declared an “unusual mortality event” in 2019 as dozens of gray whales washed up on Pacific Ocean beaches. According to the report, in 2019 there were 34 stranded whales found on Washington beaches, and 13 in 2020.
Scientists aren't sure what has been causing the die-off.
But they believe that it is within the range of previous population fluctuations and that the number of whales may have exceeded what the environment can support.
The report said preliminary findings in several of the whales showed evidence of emaciation, but that the findings are not consistent across all of the whales examined, so more research is needed.