November 2020: Update on Gray Whale Unusual Mortality Event
In May of 2019 the U.S. National Oceanic and Atmospheric Administration’s Fisheries Service (NOAA Fisheries) announced that the elevated rate of gray whale strandings during their spring northward migration along the West Coast of the United States constituted and Unusual Mortality Event (UME). In response, NOAA Fisheries activated a working group of experts that monitor gray whales throughout their North American range to investigate these gray whale mortalities. This UME continued into 2020 with additional strandings along the Pacific coasts of Mexico, the United States, and Canada. As of October 2020 NOAA reported that a total of 384 gray whale strandings had been reported and investigated. (See NOAA Fisheries announcement: https://www.fisheries.noaa.gov/national/marine-life-distress/2019-gray-whale-unusual-mortality-event-along-west-coast)
As we reported earlier this year, LSIESP researchers monitoring the gray whales in Laguna San Ignacio and Bahía Magdalena, Baja California Sur, Mexico detected indications an impending UME as early as winter 2018 and again in 2019. Specifically, they documented declining calf counts in the breeding lagoons, increasing percentages of “skinny” and “emaciated” whales, and the late arrival of the whales (See previous research Blogs at: https://www.sanignaciograywhales.org/research/research-blog/ ).
LSIESP researchers provided the NOAA UME working group two presentations of their observations of stranded gray whales in Mexico. The first report summarized the known gray whale strandings that occurred from winter 2019 to winter 2020 in Baja California and other locations in Mexico.
The second report summarized observations of the body condition of gray whales observed by LSIESP researchers in Laguna San Ignacio, Laguna Ojo de Liebre, and Bahia Magdalena in Baja California Sur, Mexico.