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Historical Timeline

The 40-year history of The Marine Mammal Center has been rich with momentous events, groundbreaking achievements, and heartwarming stories. Take a look back through the years at this amazing story.


Lloyd Smalley, Paul Maxwell, and Pat Arrigoni establish the California Marine Mammal Center on the site of a former Nike missile site in the Marin Headlands. Permits are acquired, money is raised, and the site is prepared for transformation into a rescue hospital. A sea lion named Herman, with roundworms and tapeworms, is the first patient to be treated and released.


The first school groups take field trips to the Center. This is the beginning of an educational focus that is a key component of the Center's work. The ongoing educational programs have since inspired thousands of schoolchildren to become good ocean stewards and supporters of marine mammals.


The Center publishes its first scientific paper, Nursing Care of Stranded Northern Elephant Seals, co-authored by Lloyd Smalley. This is the first of hundreds of publications in peer-reviewed scientific journals that establish the Center as an important contributor to research on marine mammal health, clinical techniques, and the state of the ocean.


Humphrey, a humpback whale, deviates from his Mexico to Alaska migration and enters San Francisco Bay. He swims 69 miles into the freshwater of the Sacramento Delta, finally stopping at the small town of Rio Vista. The Center, assisted by the United States Coast Guard and hundreds of volunteers, leads the successful response to return him to the ocean.


California sea lions start showing up in large numbers at PIER 39 in San Francisco. The Center collaborates with PIER 39 management to begin monitoring the animals and conducting educational programs. As many as 1,700 sea lions can be seen at PIER 39 on any given day, especially during the wintertime.


Humphrey the humpback whale visits again, getting stuck in the mud at Candlestick Point in San Francisco. The Center cares for him at low tide and frees him at high tide. He is guided back to the ocean with a combination of noise stimuli. Recordings of whales preparing to feed are broadcast in front of him, while a flotilla of boats behind him makes unpleasant noises.


The California Marine Mammal Center drops "California" from the name and becomes The Marine Mammal Center. The name change is in recognition of the scope of the Center's work and how it has an impact far beyond the borders of California. The work of The Marine Mammal Center is truly global in nature.


The climate phenomenon known as El Niño causes a disruption in the food supplies of marine mammals along the California coast. This results in a large number of marine mammals - especially sea lions, suffering from malnutrition and stranding. In one day the Center cares for a record 210 patients.


The Marine Mammal Center Interpretive Center and Store opens at PIER 39 in San Francisco. The new interpretive center helps visitors understand and appreciate the boisterous groups of sea lions that crowd the small floating docks alongside the pier, while the store helps raise money to support the Center's work.


The first sea otter patient is admitted for treatment at The Marine Mammal Center. Since that time, more than 200 sea otters have been rehabilitated at the Center. The southern sea otter is classified as Threatened under the Endangered Species Act and currently has a population of about 2,800 animals in California.


Another El Niño phenomenon occurs in the Pacific Ocean, coinciding with an algal bloom that produces domoic acid. The Marine Mammal Center is the first organization to diagnose domoic acid toxicity in marine mammals and produces a number of reports on the findings. The Center rescues a record 1,129 animals.


The Geoffrey C. Hughes Harbor Seal Hospital and Sara Hart Kimball Marine Mammal Surgery Center opens. This facility is separate from the areas of the Center that are open to the public, and is specifically designed to reduce stress in highly sensitive harbor seals. It also provides a state-of-the-art surgery center for the Center's veterinarians.


During the filming of Lord of the Rings, sound engineer David Farmer visits the Center at the height of pupping season. He records the howling of elephant seal pups and uses the recordings as a basis for the sound made by Orcs in the movie. The more savage Uruks are given the voice of barking sea lions.


With the generous help of Duke Energy, The Center's Monterey Bay Operation (MBO) moves to a new and improved location in Moss Landing. Since then, MBO has grown to eighty volunteers and one staff member. They rescue animals from both Santa Cruz and Monterey counties, and also act as a relay stop between operations in San Luis Obispo and Sausalito.


Chippy, an adult California sea lion, is rescued after he swims 60 miles inland, causing a major media blitz. He climbs up onto the trunk of a California Highway Patrol (CHP) car near Los Baños, hence the origin of his name. A bullet in his head is removed by veterinarians at the Center before he is released back to the ocean.


The Marine Mammal Center enters its 30th year by breaking ground for the new Morro Bay Rescue and San Luis Obispo Triage Center. This satellite facility rescues, treats, and transports animals to Sausalito. It is later dedicated as “The Bayswater Memorial Rescue and Triage Center” in memory of donor James C. Cummings by his wife Valerie.


The Center begins the first full year of construction of its new Sausalito headquarters. The new facility is a $25 million project that features expanded research facilities, species-specific pens and pools, solar panels, a modernized, underground water filtration system, state-of-the-art buildings for veterinary, staff, and educational operations, as well special exhibitions.


Two injured humpback whales, nicknamed Delta and Dawn, swim 75 miles up into the delta of the Sacramento River. The Center leads a successful multi-agency rescue effort to lead the whales back to the ocean while international media takes in the spectacle. Center veterinarians, in a first, administer antibiotics to the free swimming ill pair.


The Nova documentary Ocean Animal Emergency profiles the Center, describing it as "part emergency room, part rehab facility, and part research lab." Featuring Dr. Frances Gulland, Senior Scientist at the Center, it tells how our important work "...means the difference between life and death for sick and injured ocean animals.


The Marine Mammal Center ushers in a new era by opening up its newly rebuilt Sausalito headquarters in June. The new buildings include a better hospital, modern research facilities, and improved access for the public. That same year, volunteers and staff responded to 1,704 marine mammals in distress - a record in the Center's history.


Silent Knight, a 336-pound male California sea lion, is rescued on a beach in Sausalito. He is found to have multiple gunshot fragments in his skull and has been blinded in both eyes. His injuries are severe enough to prevent a release back to the wild, so after a successful rehabilitation at the Center, a home is found for him at the San Francisco Zoo.


The Marine Mammal Center rescues its 10,000th sea lion. After receiving more than 1,000 name suggestions from our volunteers, members, and supporters, the animal is given the name Milestone, appropriately enough. He is rescued at the Santa Cruz Boardwalk and diagnosed with leptospirosis - a bacterial infection that affects the kidneys.


Groundbreaking takes place for the Hawaiian Monk Seal Hospital at Kailua-Kona, on the Big Island of Hawaii. Known as Ke Kai Ola (The Healing Sea), the facility will aid the survival of the most endangered pinniped in the United States. There are only approximately 1,100 Hawaiian Monk Seals in the wild, and their numbers have been decreasing at an alarming rate.


The Center has another momentous year, helping out with a sea lion crisis in Southern California, celebrating the highest ever survival rate for harbor seals, and conducting cataract surgery on an elephant seal! A detailed history, entitled The Marine Mammal Center, How It All Began - Recollections of One of the Founders, is written by Pat Arrigoni.


The Marine Mammal Center opens Ke Kai Ola, the new Hawaiian Monk Seal Hospital at Kailua-Kona, on the Big Island of Hawaii. The first patients are brought in and four of them are released back to the ocean.


The Marine Mammal Center celebrates its 40th year amid a large influx of patients. For the third year in a row, hungry sea lion pups are stranding along the coast of California and in need of rescue by the Center.


The "Elliepocalypse" washes ashore as the Center rescues a record breaking number of elephant seal pups. A total of 133 elephant seals were treated and released at the Center in 2016, the most ever in a single year.


Retrofitting pens for otter rehabilitation - The Marine Mammal Center bolsters southern sea otter conservation efforts with new rehabilitation space. Newly retrofitted pens at its Sausalito headquarters allow the Center to increase efforts to advance global ocean conservation and the recovery of this threatened species.


Leptospirosis Outbreak - More than 220 California sea lions are impacted as the Center responds to the second largest leptospirosis outbreak on record. Researchers study potential long-term implications of future environmental disturbances on ecosystem health, such as infectious disease.


Increased Cetacean Research and Response Efforts - The Marine Mammal Center expands capacity to respond to entangled whales and reduce these tragic occurrences. The addition of experts from two Bay Area nonprofits, Golden Gate Cetacean Research and California Whale Rescue, uniquely position the Center to lead research and response efforts.


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