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Creature Feature: The Hawaiian Monk Seal is an endangered species

A Hawaiian monk seal lies on a beach with the ocean of the right and foliage and palm trees on the left.

The Hawaiian monk seal, according to the National Oceanic and Atmospheric Administration (NOAA), is one of the world’s most endangered species of seal. For 60 years, their population has been declining, and their current population level is only one-third the amount it once was. According to the NOAA, the current population count has surpassed 1,500.

However, NOAA stated on its website the population is rising. It credits this to its recovery efforts, such as habitat protection and vaccinating wild seals against viruses.

The American Oceans site states if the Hawaiian monk seal were to go extinct, the Hawaiian ecosystem would be devastated. Monk seals are apex predators and have an important role in the food chain keeping crustacean, fish and squid populations under control.

According to a National Geographic profile on monk seals, they live between 25 to 30 years and can weigh up to 600 pounds. From nose to back flipper, they grow to be about 7 feet long.

The Oceana website states monk seals are usually solitary when they’re not breeding or raising pups. They can dive up to 1,800 feet in the water, and their main predator is the tiger shark.

Hawaii Marine Animal Response (HMAR) information says beach visitors should stay at least 50 feet away from monk seals, and 150 feet away if the monk seal is a mother with a pup. If HMAR or NOAA-sanctioned personnel are present, follow their instructions, as harassing a monk seal is illegal under the Endangered Species Act and can cost thousands of dollars in fines.

If the Hawaiian monk seal were to go extinct, the Hawaiian ecosystem would be devastated. Monk seals are apex predators and have an important role in the food chain keeping crustacean, fish and squid populations under control.
The American Oceans Website

The monk seal’s Hawaiian name is “ilio holo i ka uaua,” which the Marine Mammal Center translates as “dog that runs in rough water.” They are found only in Hawaii, making them an endemic species, according to the Marine Mammal Center.

The Marine Mammal Center explains most monk seals are part of six main breeding populations: Kure Atoll, Midway Islands, Pearl and Hermes Reef, Lisianski Island, Laysan Island and the French Frigate Shoals.

These islands are all found in Papahanaumokuakea Marine National Monument, the mostly unpopulated northwestern islands in the Hawaiian archipelago. The Center for Biological Diversity says on its website more and more monk seals are moving to the main islands, such as Oahu, where pups have a better survival rate.

Another less natural threat to the monk seal is a protozoal disease called toxoplasmosis. NOAA has documented at least 11 monk seal deaths to toxoplasmosis since 2011. Toxoplasmosis is spread through the droppings of cats infected with the disease, meaning that Hawaii’s large population of feral cats has become an indirect threat to the endangered monk seal, according to NOAA.

NOAA encourages people to report monk seal sightings to its local NOAA Marine Wildlife Hotline at (888) 256-9840.