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Hawaiian Monk Seal Conservation, And How Divers Help

Having had numerous occasions to observe Hawaiian monk seals while diving, it is hard to imagine they are one of the most endangered marine mammals in the world. These puppy-faced, inquisitive animals are fun to observe in the water. Found only in the Hawaiian islands, monk seals have a total estimated population of about 1,200, making them the rarest seal species.

Photo: NOAA

Pupping season is around the corner! Although monk seal pups can be born any time of year, most are born spring through summer. Females will come ashore to give birth, and nurse their pups for 5 to 7 weeks, feeding them milk rich in fat that will increase their weight from 30 pounds at birth to nearly 200 pounds! The pup will live off of its body fat as it practices foraging, venturing farther into nearshore waters and eventually head out to sea. Females often return to the beaches on which they were born to birth their pups.

An endangered species

Hunted to the brink of extinction in the late 19th century, the Hawaiian monk seal population declined for many years.

The Hawaiian monk seal was officially designated as an endangered species on November 23, 1976. The main threats Hawaiian monk seals face in the Northwestern Hawaiian Islands are maternal separation, malnutrition, predation, habitat loss and entanglement or ingestion of ocean trash. Those that live in the main Hawaiian Islands face additional threats like toxoplasmosis and negative human interactions.

Under the Endangered Species Act and the Marine Mammal Protection Act it is illegal to kill, capture, or harass a Hawaiian monk seal. Even observing, humans should keep their distance. While considered gentle in nature, adult seals can be aggressive if pups are around or if they feel threatened.

Fortunately, the species has started to show an increase in numbers as conservation efforts have increased. In fact, about 30 percent of today’s Hawaiian monk seal population is alive directly due to conservation efforts led by the National Oceanic and Atmospheric Administration (NOAA).

Photo: James Watt, USFWS

Scuba divers can play a role in conservation efforts by reporting the GPS location of monk seals. Report all sightings, injuries and strandings to 808-220-7802 or email [email protected]. Note that monk seals do come ashore to rest. NOAA professionals and their partners can monitor them, rope off a section of beach if necessary, or take other action. Reporting by the diving community helps NOAA’s conservation efforts and to monitor the monk seal population in Hawaii.

The best way to observe Hawaiian monk seals in nature is to get out and dive. We have respectfully observed monk seals at all of our dive sites, at the surface, underwater, on ledges or along the shore. Sightings cannot be guaranteed, but the more you are on and in the water, the better chance of observing these mammals which ancient Hawaiians called ‘Ilio holo I ka uaua (dog that runs in rough water).