Hakai Magazine: How Terrestrial Turds Lead to Marine Maladies
- Parasites
- Pathology
- Toxoplasmosis
Diseases from land animals are killing marine mammals at an alarming rate.
Published in Hakai Magazine: January 2, 2024
For marine mammals, changes in ocean temperature and chemistry caused by a warming climate and pollution may be contributing to immunosuppression. Dr. Cara Field, Medical Director at The Marine Mammal Center explains that this could be making animals more susceptible to sarcocystosis and other diseases.
“These contaminants and pollutants often affect our immune systems,” she says. “We know that when an animal’s immune system is compromised, they are more susceptible to disease and severe parasitic infections, which is very concerning.”
Even as the Center’s network of first responders grows and care improves as the world’s largest marine mammal hospital, marine mammals will continue dying from these diseases, says Field. And that is because of the diffuse, complex, and global nature of the problem: namely our land-devouring, planet-altering industrial society.
She adds, “The more that we change and exploit our natural environment…the more we remove those natural barriers that nature has established over eons to help filter out things like these protozoal pathogens.”
Meet the Featured Patient
Decker the California sea lion had been diagnosed with sarcocystis. After four months of treatment and recovery at the Center, he was released back to the wild at Point Reyes National Seashore.
Read more about Decker
Disease Research at The Marine Mammal Center
As the world’s largest marine mammal hospital, the Center learns from the hundreds of animals we rescue each year to help us all better understand the health of the ocean environment.
{"image":"\/Animals\/Patients\/Hawaiian monk seals\/2020\/cropped-images\/hms-pohaku-pre-rescue-photo-c-hawaii-marine-animal-response-0-0-640-500-1603150844.jpg","alt":"Hawaiian monk seal P\u014dhaku resting on Oahu before rescue","title":"Endangered Hawaiian Monk Seal Battling Toxoplasmosis","link_url":"https:\/\/www.marinemammalcenter.org\/news\/endangered-hawaiian-monk-seal-battling-toxoplasmosis","label":"Patient Update","date":"2020-02-20 04:00:00","type":"news"}
{"image":"\/Animals\/Patients\/California sea lions\/2019\/csl-gunther-by-bill-hunnewell-c-the-marine-mammal-center.jpg","alt":"","label":"Research Library","title":"Leptospirosis","link_url":"\/science-conservation\/research-library\/leptospirosis","type":"page"}
{"image":"\/Animals\/Patients\/California sea lions\/cropped-images\/csl-eating-by-bill-hunnewell-c-the-marine-mammal-center-0-361-1799-1405-1617816863.jpg","alt":"California sea lion eating a fish","title":"Predicting Prognosis in Wildlife Rehabilitation: A Case Study of Leptospirosis in Sea Lions","link_url":"https:\/\/www.marinemammalcenter.org\/publications\/predicting-prognosis-in-wildlife-rehabilitation-a-case-study-of-leptospirosis","label":"Research Paper","type":"publication"}
Predicting Prognosis in Wildlife Rehabilitation: A Case Study of Leptospirosis in Sea Lions
Read More{"image":"\/Animals\/Patients\/California sea lions\/2021\/cropped-images\/csl-bottlecap-by-bill-hunnewell-c-the-marine-mammal-center-1070-538-2499-1952-1630538744.jpeg","alt":"California sea lion Bottlecap","title":"Treating California Sea Lions with Sarcocystis-Associated Multi-Phase Muscle Breakdown","link_url":"https:\/\/www.marinemammalcenter.org\/publications\/treating-california-sea-lions-with-sarcocystis-associated-multi-phase-muscle-breakdown","label":"Research Paper","type":"publication"}
Treating California Sea Lions with Sarcocystis-Associated Multi-Phase Muscle Breakdown
Read MoreYes, I want to save a life!
Yes, I want to save a life!
You’ll be giving sick and injured animals the best possible care at the Center’s state-of-the-art hospital. With your gift today, you are giving a patient a second chance at life in the wild.
See Our Latest News
{"image":"\/Animals\/Wild\/Sea otter\/so-wild-morro-bayphoto-c-brian-simuro-20.jpeg","alt":"Sea otter and pup","title":"Watch a Sea Otter Pup Reunite With Its Mother","link_url":"https:\/\/www.marinemammalcenter.org\/news\/watch-sea-otter-pup-reunite-with-its-mother","label":"News Update","date":"2025-11-14 10:35:41"}
{"image":"\/Animals\/Wild\/Sea otter\/sea-otter-photo-c-brian-simuro.jpeg","alt":"Sea otter","title":"AP News: Baby sea otter is reunited with mother in central California after dramatic rescue","link_url":"https:\/\/www.marinemammalcenter.org\/news\/ap-news-baby-sea-otter-is-reunited-with-mother-in-central-california-after-dramatic-rescue","label":"In the News","date":"2025-11-14 09:46:34"}
AP News: Baby sea otter is reunited with mother in central California after dramatic rescue
November 14, 2025
Read More{"image":"\/Animals\/Patients\/Harbor seals\/2013\/cropped-images\/hs-bogey-by-ingrid-overgard-c-the-marine-mammal-center-371-0-2712-2118-1607385758.jpg","alt":"harbor seal Bogey","title":"Top Holiday Gifts for Ocean Lovers","link_url":"https:\/\/www.marinemammalcenter.org\/news\/top-eco-friendly-holiday-gifts-that-give-back","label":"News Update","date":"2025-11-04 01:00:00"}
{"image":"\/Animals\/Wild\/Hawaiian monk seal\/cropped-images\/hms-wild-photo-1-c-noaa-pifsc-hmsrp-35-0-1270-992-1759760452.jpg","alt":"A Hawaiian monk seal rests on its side on a sandy beach.","title":"Where Do Hawaiian Monk Seals Live? And Other \u2018\u012alio Holo I Ka Uaua Trivia","link_url":"https:\/\/www.marinemammalcenter.org\/news\/where-do-hawaiian-monk-seals-live-and-other-ilio-holo-i-ka-uaua-trivia","label":"News Update","date":"2025-10-06 00:00:00"}
Where Do Hawaiian Monk Seals Live? And Other ‘Īlio Holo I Ka Uaua Trivia
October 6, 2025
Read Morepathology
toxoplasmosis
Cara Field
Pádraig Duignan
California Sea Lion