Estimated population:
13,000 - 14,000 seals occurring only
in the Hawaiian Archipelago and is listed as an endangered species
under The Endangered Species Act.
Ways to identify this species:
Adults
are generally light gray while pups are often black or dark gray. At
maturity, this species reaches from 6 feet 11 inches to 7 feet 10
inches and weighs from 510 to 600 pounds.
Biology
- Monk
seals mainly occupy the uninhabited atolls of the Northwestern Hawaiian
Islands; however, some have been spotted around the Main Hawaiian
Islands.
- The monk seal depends largely on the coral reefs for feeding. Their diet consists of fish, eels, octopuses, and crustaceans.
- Monk seals are very fast and efficient swimmers; they can travel long distances and dive over 800 feet.
- After
four years, females reach sexual maturity but do not bear young until
age 6 or 7. Similar to other species of seal, monk seals only bear 1
young per year. Although 90 percent of pups survive to weaning, in
recent years, survival of pups post-weaning has been as low as 30
percent in some areas. There were 8 pup deaths this year at the French
Frigate Shoals.
Threats
- Skewed
male to female ratios due to low pup survival rates have led to groups
of aggressive males attempting to mate with a single female and with
pups resulting in mortal wounds.
- Fishery-related deaths
play a major role in low populations. Each year, around 10 monk seals
wash ashore entangled in fishing nets, while others become entangled in
marine debris, are disturbed at haul-out sites or become poisoned by
contamination.
- Natural threats such as shark predation, a
decline in atoll productivity, intra-species aggression by large males,
and a loss of pupping habitat likely due to sea-level rise also
threaten monk seal populations. A natural catastrophe such as a disease
outbreak could lead this species to extinction.