Newsweek: Mystery As Harbor Porpoises Found 60 Miles Upstream in San Francisco
- Behavior
- Natural history
Mystery As Harbor Porpoises Found 60 Miles Upstream in San Francisco
Published in Newsweek: October 26, 2022
Two harbor porpoises that entered the San Joaquin River near San Francisco in September have now traveled even further upstream.
The mother and calf were spotted near Bethel Island in the San Joaquin River on September 25, 60 miles inland from the ocean.
"This year, we had a sighting of a mother and her dependent calf far upriver, into the lower San Joaquin River east of Bethel Island, on September 25, and three days later, a mother-calf pair was seen farther down river in the town of Pittsburg, California," Bill Keener, a researcher and member of the Cetacean Field Research Team at The Marine Mammal Center, told Newsweek.
Harbor Porpoise Research at The Marine Mammal Center
Harbor porpoises have returned to San Francisco Bay after an absence of approximately 65 years. The Center's Cetacean Field Research Team is conducting a multi-year assessment to document this population’s abundance and distribution, as well as to examine their social behavior and calving success.
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Coevolution of Asymmetric and Spiraled Genitalia with Unique Mating Behavior
Read More{"image":"\/Animals\/Wild\/Harbor porpoise\/harbor-porpoise-shutterstock-2.jpg","alt":"harbor porpoise","title":"Harbor Porpoises Catching and Handling Large Fish","link_url":"https:\/\/www.marinemammalcenter.org\/publications\/harbor-porpoises-catching-and-handling-large-fish","label":"Research Paper","type":"publication"}
{"image":"\/Animals\/Wild\/Harbor porpoise\/cropped-images\/harbor-porpoise-by-bill-keener-c-the-marine-mammal-center-309-73-1207-943-1610670087.jpg","alt":"Harbor porpoise surfacing in the water","title":"The Sex Life of Harbor Porpoises: Lateralized and Aerial Behavior","link_url":"https:\/\/www.marinemammalcenter.org\/publications\/the-sex-life-of-harbor-porpoises-lateralized-and-aerial-behavior","label":"Research Paper","type":"publication"}
{"image":"\/Animals\/Wild\/Harbor porpoise\/cropped-images\/harbor-porpoises-foraging-by-marc-webber-c-the-marine-mammal-center-4-0-1276-996-1618438446.jpg","alt":"harbor porpoises eating a large fish","title":"Prey-Related Suffocation in Harbor Porpoises","link_url":"https:\/\/www.marinemammalcenter.org\/publications\/prey-related-suffocation-in-harbor-porpoises","label":"Research Paper","type":"publication"}
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Bill Keener
Harbor Porpoise