In this May 24, 2019 file photo, teachers and students at Northwest Montessori School in Seattle examine the carcass of a gray whale after it washed ashore on Washington’s Olympic Peninsula, north of Camp Kalaloh in Olympic National Park. US researchers say the number of gray whales in western North America has continued to decline over the past two years, a decline that echoes previous population fluctuations over the past few decades. According to a NOAA Fisheries estimate released on Friday, October 7, 2022, the population was last counted at 16,650 whales, down 38% from the 2015-16 peak. Credit: AP Photo/Gene Johnson, file
US researchers say the number of gray whales in western North America has continued to decline over the past two years, a decline that echoes previous population fluctuations over the past few decades.
According to an estimate released Friday by the National Oceanic and Atmospheric Administration, the latest count population at 16,650 whales, down 38% from the peak in 2015-16. Whales also produced the lowest number of calves since scientists began counting births in 1994.
An increase in the number of whales washing up on West Coast beaches has prompted the fisheries agency to declare an “unusual die-off” in 2019. Researchers are still investigating the die-off, but they say climate change and its effect on sea ice and the availability and location of prey are likely factors. Many, but not all, of the beached whales appeared malnourished.
The population recovered from the days of commercial whaling before a similar population decline of 40% in the late 1980s and early 1990s. Gray whales were removed from the village list of endangered species in 1994.
The population recovered before another “extraordinary mortality” was declared in 1999 and 2000, when the number of whales was reduced by a quarter.
Scientists say that while current population fluctuations so far fit within historical patterns, they are still a cause for concern.
“We need to monitor the population closely to understand what might be driving this trend,” said David Weller, director of the marine mammal and turtle division at the Southwest Fisheries Science Center in San Diego.
Researchers count the whales as they return from their summer feeding grounds in the Arctic to the lagoons of the Baja Peninsula, where they nurse their calves in the winter. Censuses are typically conducted over two years, but to better monitor the population, NOAA Fisheries is adding a third year to the current study, counting whales as they pass the central California coast from late December to mid-February 2023.
Calves are counted when the whales head north to the Arctic. There were 217 of them calves in the count that ended in May, compared with 383 a year earlier.
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