Center for Whale Research | An update on J36

||| FROM CENTER FOR WHALE RESEARCH |||

On September 12, 2025, researchers at CWR, along with our colleagues at SR3 and SeaDoc Society, documented 26-year-old female southern resident J36 carrying a dead female calf. Sadly, reproductive failure, either due to miscarriage or death shortly after birth, is the rule rather than the exception in the southern resident population. This is not J36’s first experience of losing a calf. In 2017, she lost her 2-year-old son J52, her only calf ever documented alive. Since then, she has experienced multiple pregnancy failures.

These whales have exceedingly low reproductive rates compared to other killer whale populations, even those living in the same waters. While the mammal-eating Bigg’s killer whales are thriving in the Salish Sea and growing their population, the southern residents continue to decline.

There are numerous pressures that impact the southern residents, and it’s not possible to assign any one cause to this calf’s death. Pollutants, especially polychlorinated biphenyls, likely contribute to reproductive failure in this and other marine mammal populations, while disturbance and noise make it harder for these animals to forage. However, the research is clear that the single biggest threat facing these whales is a lack of prey, particularly a lack of large Chinook salmon. If drastic action isn’t taken to recover Chinook populations, we will continue to see reproductive failure in this population.

These whales are resilient and will take whatever opportunity is given to them to recover. J36 herself gives us an object lesson in this fact. Researcher Maya Sears shared with us that J36 has since been sighted in Puget Sound. She has let go of her calf and has been observed socializing with the other whales of J pod, especially the younger individuals. The southern residents can bounce back from the damage that’s been done to them. All they need is for us to give them a chance.