Adult Hawaiian monk seal Pōhaku is suffering from a potentially lethal parasitic infection called toxoplasmosis, a leading cause of death in monk seals.
February 20, 2020
The Marine Mammal Center has admitted an adult female Hawaiian monk seal named Pōhaku to Ke Kai Ola, our hospital on the Big Island of Hawai‘i, for long-term care and treatment for toxoplasmosis, a parasitic infection known to be deadly to monk seals.
In late January, Pōhaku was spotted in the waters off the coast of Oahu logging, a behavior in which a monk seal inactively floats on the ocean’s surface for an extended period. This particular monk seal is known to have a history of logging in this area for about a day at a time. But when she appeared to be behaving lethargically two days in a row, experts became concerned.
Hawaiian monk seal Pōhaku resting on Oahu before rescue. Photo © Hawai‘i Marine Animal Response
Once responders were able to safely rescue Pōhaku, she was transported to NOAA’s Inouye Regional Center (IRC) on Oahu, where she underwent an examination guided by Dr. Michelle Barbieri, an alumni of the Center’s Teaching Hospital who now leads the Hawaiian Monk Seal Response Program at NOAA.
Upon admit to the IRC, Pōhaku was alert, responsive and appeared to have no obvious physical injuries. The veterinary team suspected that she may be suffering from gastrointestinal upset, so they gave her treatment for that as well as antibiotics and other supportive care.
Experts from NOAA and The Marine Mammal Center teaming up to treat Hawaiian monk seal Pōhaku. Photo © NOAA / NOAA permit #18786
But Pōhaku’s blood work revealed an extremely worrisome result: she was diagnosed with toxoplasmosis, a potentially deadly disease that can cause brain infection and muscle tremors. Toxoplasmosis is a leading cause of death in monk seals and also affects other marine mammals, such as southern sea otters, a threatened species.
The Marine Mammal Center has rehabilitated other marine animals, like southern sea otter Yankee Doodle, suffering from toxoplasmosis. Photo by Bill Hunnewell © The Marine Mammal Center / USFWS permit MA101713-1
For an animal of Pōhaku’s size (she initially weighed in at over 480 pounds!), treatment can be intense and challenging, requiring a long course of medication that can be taxing on the patient. Staff from our animal care team based in Kona, Hawai‘i, regularly supported Pōhaku’s treatment on Oahu before she was transported to Ke Kai Ola for long-term care.
“As the only partner organization permitted by NOAA to treat and rehabilitate endangered Hawaiian monk seals, we’re proud to be able to support patients like Pōhaku at our state-of-the-art facility in Kona,” said Megan McGinnis, the Center’s Animal Care Program Manager at Ke Kai Ola.
The U.S. Coast Guard helped transport Hawaiian monk seal Pōhaku to The Marine Mammal Center’s hospital on the Big Island, Ke Kai Ola. Photo by Sheila Latta © The Marine Mammal Center / NOAA permit #18786
You may remember that we currently have four other female Hawaiian monk seals in our care, who are housed together. However, Pōhaku will be in her own pen as she is currently weak, lethargic and in need of rest.
Pōhaku cannot transmit toxoplasmosis to the other patients because this infection is caused by a common parasitic protozoan called Toxoplasma gondii, which can only reproduce in a cat’s gut. Both domestic and wild cats shed the parasite’s oocysts, or egg-like structures, in their feces.
The oocysts are able to survive for months in extreme environmental conditions and therefore can contaminate the ocean food chain through disposal of cat litter in the toilet or from outdoor cats that live near natural water sources. Marine mammals like Hawaiian monk seals are then exposed to this parasite’s eggs by consuming contaminated prey or water.
Toxoplasmosis is a leading cause of death in Hawaiian monk seals. Graphic © NOAA
Along with ocean trash and sea level rise, toxoplasmosis is one of the main threats facing the endangered Hawaiian monk seal population, partly because the infection is so difficult to detect. Most monk seals with toxoplasmosis are found dead without warning; only two other seals have been rescued prior to death and both succumbed to the disease within 48 hours of rescue.
Pōhaku has survived longer than any other monk seal with toxoplasmosis but her prognosis is still guarded, and treatment will be decided on a day-by-day basis.
Because no vaccine is available for toxoplasmosis, preventative measures must be taken by people like you. It’s easy to help protect endangered Hawaiian monk seals like Pōhaku from toxoplasmosis—simply dispose of cat litter in the trash, keep your cats safe indoors and tell your community about how they too can prevent this disease from harming more marine mammals.
We are proud to partner with NOAA to support conservation efforts for the Hawaiian monk seal. NOAA researchers estimate the current monk seal population to be about 1,400 animals—about 30 percent of those monk seals are alive today directly due to conservation efforts led by NOAA and partners like us.
About 30 percent of Hawaiian monk seals are alive today due to conservation efforts led by NOAA and partners like The Marine Mammal Center. Photo by Sheila Latta © The Marine Mammal Center / NOAA permit #18786
You Can Be a Hawaiian Monk Seal Hero
You see, human activity has put the Hawaiian monk seals’ world in turmoil and is leading them toward extinction. But you can lend a helping hand and make a real difference for this endangered species when you give today to support conservation efforts as well as the long-term care needed for patients like Pōhaku.
Thank you for caring about marine mammals and their ocean home.