February 2021 Field Report


After a slow start in January the number of gray whales observed in Laguna San Ignacio and in Bahía Magdalena gradually began to increase throughout the month of February. While these increases were the result of more single whales arriving at theses lagoons, the number of female-calf pairs continued to remain very low compared to previous surveys before the winter of 2018. Beginning in 2018, female-calf counts in Laguna San Ignacio and Bahía Magdalena were no more than 20 pairs from 2018 to the present 2021 winter. This suggests that gray whale reproduction remains low, perhaps as the result of the Unusual Mortality Event (UME) that began in 2019.

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When the gray whales arrive in Baja California in early January, they have completed their summer of feeding areas in the North Pacific, Bering and Chukchi seas and migrated south to the breeding areas along Baja California’s Pacific coast. Gray whales are very efficient swimmers and should arrive on the breeding grounds in very good condition. It continues to be alarming that many of them are underweight, and this suggests that the Unusual Mortality Event (UME) is continuing in 2021.

Read more about additional sightings “skinny” whales in poor body condition observed in the 2021 winter, and the number of stranded gray whales discovered in both areas during January and February in the complete Field Report for February  2021 at this link.

Learn how you can become a supporter of our gray whale research in Laguna San Ignacio and Bahía Magdalena by making a recurring donation to our program


Silber, G. K., et al. February 25, 2021. Co-occurrence of gray whales and vessel traffic in the North Pacific. Endangered Species Research. Vol. 44:177-201.

Christiansen, F., et al. January 21, 2021. Poor body condition associated with an unusual mortality event in gray whales. Marine Ecology Progress Series Vol. 658:237-252.

Stewart, J.D. and Weller, D.W. January 2021. Abundance of Eastern North Pacific gray whales 2019/2020. NOAA Technical Memorandum NOAA-TM-NMFS-SWFSC-639, https://repository.library.noaa.gov/view/noaa/27928

Huntington, et al. February 24, 2020. Evidence suggests potential transformation of the Pacific Arctic ecosystem in underway.  Natura Climate Change, www.nature.com/natureclimatechange; https://doi.org/10.1038/s41558-020-0695-2.

Urban, et al. (In Press) Migratory behavior of an Eastern North Pacific gray whale from Baja California Sur to Chirikov Basin, Alaska. Frontiers Online Publication.

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