 
        
          Ton Jefferson: "Flashing red lights amidst a black and white porpoise: Dall's porpoise declines along the west coast of North America"
Dall’s porpoise is a cetacean you won’t forget if you’ve ever seen one or a group of them – they are powerful fast swimmers that rip so rapidly across the surface they create a characteristic spray known as a “rooster tail” – a thrilling display. Recently there has been concern about the apparent decreasing numbers of Dall’s porpoise in the eastern North Pacific (ENP). In early 2025, the ACS-SFBay chapter awarded a research grant to Dr. Thomas Jefferson to address the concerns and evaluate available evidence for population declines. Please join us to hear from our grantee on the results of his study, evidence of the decline along the west coast, and suggested next steps for our understanding of threats to the Dall’s porpoise population.






























