
SFGATE: The Secret Sex Lives of Harbor Porpoises Under San Francisco's Golden Gate Bridge
- Behavior
- Natural history
The species has a “funnel of love” below the city's most well-known landmark.
Published in SFGATE: December 7, 2023
Bill Keener’s eyes widened as he peered through his binoculars and spotted the dark, shiny dorsal fins swiftly bobbing along the surface of San Francisco Bay. “There’s three of them coming right at us,” he said.
It was a drizzly Tuesday morning in November, and the Marine Mammal Center field researcher and I had been wandering along the pedestrian walkway on the Golden Gate Bridge for about an hour. Cars whooshed past us as we dodged bicyclists and paused at lookout points, keenly peering over the steel railing toward the murky turquoise water about 200 feet below. We were hoping to catch a glimpse of the species he’s been closely tracking for decades: the harbor porpoise, a shy yet charismatic creature that nearly disappeared from the bay altogether.
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"}

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natural history
Bill Keener
Harbor Porpoise