The largest and perhaps the most intimidating mammal living on St. Paul (aside from humans) is the Northern Fur Seal (Callorhinus ursinus). "Discovered" in the late 18th century, the Northern Fur Seal quickly became a prized catch for commercial hunters from the USA, Japan, Russia and the UK. With 300,000 hairs per square inch the seals pelts fetched a handsome price. For comparison, your average dog has approximately 60,000 hairs per square inch. Commercial hunting almost lead to the extinction of these seals by the late 19th century. Thanks to many treaties and the Marine Mammal Protection Act, these seals have rebounded to a population estimate of 1.1 million animals. This sounds like a lot until you consider the population was around 2.1 million in the 1950's. The population is now in decline even though the only legal hunting is done by native Aleut in a subsistence harvest. Between 1999-2003 the average annual harvest was 869 animals, all juvenile or sub-adult males. This number has dropped to 478 in 2007 and continues to remain low.
The Marine Mammal Protection Act makes it illegal to harass, hunt, capture, or kill, or attempt to harass, hunt, capture, or kill any marine mammal. The term “ harassment” means any act of pursuit, torment, or annoyance and they take this law very seriously on St Paul. Two viewing blinds are set up for people to observe the seals at two different rookery sites and visitors must be accompanied by officials.
The Northern Fur Seal was first named "sea-bear" which is related to their scientific name, ursinus, meaning "bear-like". As with other seal species, pups are born with black pelts earning them the nickname 'black coats'. Males grow up to 385-605 pounds and females range 66-110 pounds. Their natural predators are orca, great white shark and occasionally pups will fall victim to hungry foxes.