
The Press Democrat: Flurry of Sick and Dying Sea Lions Believed to be Caused by Bacterial Disease
- Leptospirosis
Sea lions have been washing ashore sick and dead from infectious bacteria. Officials at the Marine Mammal Center say they know where the sea lions were infected.
Published in The Press Democrat: September 5, 2023
An unusual flurry of sick and dead California sea lions coming ashore in and around Bodega Bay is believed to have been caused by a wave of bacterial disease among mostly immature males returning to the coast from breeding grounds in The Channel Islands, a spokesman for The Marine Mammal Center said Tuesday.
Bodega Bay, especially Doran and Salmon Creek beaches, are among several hotspots along the California coast where an unusually high number of sea lions have been found to be suffering from leptospirosis, said Giancarlo Rulli, marketing and communications associate for the Sausalito-based marine mammal hospital, the state’s largest. Other sites with high numbers of ailing sea lions include San Luis Obispo, Monterey and Mendocino-Fort Bragg.
Leptospirosis Research at The Marine Mammal Center
The Center has been on the forefront of research on leptospirosis in marine mammals and has published a number of scientific papers on the disease dating back to 1985. And for more than 10 years, we’ve collaborated with researchers at UCLA to study the dynamics of this pathogen in the California sea lion population.
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Predicting Prognosis in Wildlife Rehabilitation: A Case Study of Leptospirosis in Sea Lions
Read More{"image":"\/Animals\/Wild\/California sea lion\/cropped-images\/sea-lions-in-water-photo-c-bill-hunnewell-2140-212-1308-1022-1603918234.jpg","alt":"large group of California sea lions in the water","title":"Detecting the Spread of Leptospirosis Through Asymptomatic Carriers","link_url":"https:\/\/www.marinemammalcenter.org\/publications\/detecting-the-spread-of-leptospirosis-through-asymptomatic-carriers","label":"Research Paper","type":"publication"}

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Read More{"image":"\/Animals\/Patients\/California sea lions\/cropped-images\/csl-by-bill-hunnewell-c-the-marine-mammal-center-5-0-1-3112-2431-1603919011.jpg","alt":"California sea lion diving into a pool","title":"First Report of Asymptomatic Carrier Transmission of Leptospirosis","link_url":"https:\/\/www.marinemammalcenter.org\/publications\/first-report-of-asymptomatic-carrier-transmission-of-leptospirosis","label":"Research Paper","type":"publication"}

{"image":"\/Animals\/Wild\/California sea lion\/cropped-images\/sea-lions-underwater-baja-shutterstock-186-4-4173-3260-1603919420.jpg","alt":"California sea lions underwater","title":"Seasonal Migration Contributes to Spread of Leptospirosis","link_url":"https:\/\/www.marinemammalcenter.org\/publications\/seasonal-migration-contributes-to-spread-of-leptospirosis","label":"Research Paper","type":"publication"}

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Giancarlo Rulli
California Sea Lion