Hawaiian Monk Seal

Hawaiian Monk Seals (Monachus Schauinslandi) are listed as “Critically Endangered” by the IUCN and are one of the most threatened of all seals. They were hunted to near extinction by commercial sealers in the mid 19th century. They suffer from a massive 80% pup mortality. Habitat loss; shark predation; decreased food availability; human disturbances; illegal killing; weather conditions; disease; males killing off of rivals and pups as well as entanglement issues all play a role in their rapidly declining numbers. They receive protection from several bits of legislation including Appendix I of CITES as well as the US Marine Mammal Protection Act, under which they are listed as “depleted.”

underwater photography, Hawaiian Monk seal, critically endangered

Hawaiian Monk Seals (Monachus Schauinslandi)


Females prefer short lengths of beach, with shallow waters for pupping and nursing. This is presumed to aid her in protecting her offspring from shark predation and rough seas.

The birthing period is a relatively long one and stretches from early February right through until mid July, though most pups tend to be born between March and May, with mothers coming to shore around a week before hand. Mating takes place at sea and is rarely witnessed.

mother with baby Hawaiian Monk seal, suckling from teat

Mother with baby

Pups are born with a black coat and weigh between 15-20 kg at birth. They measure approximately 1m long. They gain weight rapidly with one study showing them to go from 18 kg at birth to 64 kg at the time of weaning some 5 weeks later. Thereafter the pup lost 9kg and dropped back down to 55 kg.

underwater photography, Hawaiian Monk seal, stunning pic, wildlife and nature, scuba diving

Hawaiian Monk Seal (Monachus Schauinslandi)

The female does not eat during the period she spends nursing her pup. From birth to when the pup is fully weaned (around 6 weeks) the female can lose as much as 90 kg in weight.

Adult males are known to mob females, where a group of males will gang up on a female in an attempt to mate. This practice may even cause the death of the female.

Population of Hawaiian Monk seals estimated to be 1 100 individuals

Beautiful photograph


Monk Seals will show almost no flight response to humans, which undoubtedly led to their current predicament by commercial sealers.

These seals have been known to fully adopt other pups, especially if their own has died. Nursing duties are sometimes shared among females, particularly if female to male density ratios are high. This propensity has enabled humans to foster pups whose mothers have died more easily.

Monk seals interacting, Hawaii

Social interaction between Hawaiian Monk seals

Their plight was highlighted in 1990 when hooks from a swordfish longline fishery operating in the vicinity were found embedded in their mouths and skin. Pressure from environmental groups resulted in a 50 nautical mile protected species management zone around the islands, banning all pelagic fishing. A measure perhaps taken too late.

In 2010, a law was passed in Hawaii making it a criminal offence to harm these animals. A fine of up to $50 000.00 may be imposed for violations. In January of 2012, three Hawaiian Monk Seals were found bludgeoned to death. A fourth may have suffered the same fate.

photo of Monk seal underwater, scuba diving

Hawaiian Monk seal population is estimated at less than 1 100 individuals

Ongoing efforts are made to protect Hawaiian monk seals. Regular removal of marine debris from surrounding reefs is undertaken. This in an attempt to reduce entanglement statistics. In 1998, 7.5 tonnes of discarded net was collected from a 1.5 square kilometer area near French Frigate Shoals, a major pupping area. A similar operation at Hermes Reef in 1999 amassed over 23 tons of discarded nets. Over 700 tons of marine debris has been removed from the area since 1996.

In the last 50 years, Hawaiian Monk Seal populations have dropped by over 60%, despite having legal protection.

They get their name from the soft folds of fur around their necks which resembles a monks cowl as well as their solitary lifestyle. .

shark attack, monk seal, predator, shark

Sharks take a large number of Monk Seals