The Caribbean Monk Seal was also known as the West Indian Monk Seal or Sea Wolf. The first Europeans to see them in August 1494 were Christopher Columbus and his crew when their ship laid anchor off the island of Alta Velo. Their population size, prior to exploitation by Europeans and overfishing, as at the early 17th Century has been estimated at something over a quarter of a million distributed over 13 breeding colonies each 300km apart. Their average length was 2-2.4m in length and weighed about 160–200kg.
Historically, they had a widespread range throughout the warm temperate, subtropical and tropical waters of the Caribbean Sea, Gulf of Mexico, and West Atlantic Ocean. Their distribution also included the east coast of Central America and north coast of South America. In the Caribbean, they inhabited the Greater and Lesser Antilles, Cuba, Jamaica, and other local waters. There are historical records of breeding grounds in the Bahamas and Yucatan, Mexico. Little is known about their migration patterns and other movements. This was the only subtropical seal native to the Caribbean Sea and Gulf of Mexico.
Caribbean Monk Seals had a fairly large and robust body, along with a distinctive head and face. The head was rounded with an extended broad muzzle. When compared to the body, the front flippers were relatively short while the hind flippers were slender. Their coloration was brown and gray, with a lighter underside. Adults tended to be darker in colour than the pups, who were more pale and yellow. This species mainly fed in shallow lagoons and reefs on eels, reef fish, octopus, and spiny lobster.
The seals tended to lie on open beaches above high tide on isolated and secluded atolls and islands where they reared their young. These monk seals were a shallow-water species, gathering in large numbers on open beaches, where each mother would nurse her pup for about 30-50 days. They had little or no flight response to humans. Apart from this, there is no information on the seal’s behaviour and ecology. They also occasionally visited the mainland coasts and deeper waters offshore.
Caribbean Monk Seals were pinnipeds (i.e. with front and rear flippers) and had a long pupping season. In Mexico, breeding season peaked in early December. Females had four retractable nipples that their pups would nurse on. Newborn pups were probably about 1m in length and weighed 16-18kg and had a sleek, black coat when born.
When Spanish explorers arrived from Europe, hunters began killing the Caribbean Monk Seals. The seals were targeted for their fur, hides, meat and oil. Due to their non-aggressive and tame behaviour, hunters were able to get quite close to these seals. They were also captured and killed for display in museums and zoos. Fishing, coastal development and other overkill activities began disturbing the critical and vital habitat of these seals and depleting the fish and crustaceans they fed on.
In the first half of the 20th century Caribbean Monk Seal sightings became much rarer. In 1908 a small group of seals was seen at the once bustling Tortugas Islands. In 1922 there were no seals left in the entire northern Caribbean. There were sightings of Caribbean Monk Seals on the Texas coast in 1926 and 1932. The last seal recorded as killed by humans was on the Pedro Cays in 1939. Two more seals were seen on Drunken Mans Cay, just south of Kingston, Jamaica, in November 1949. The last confirmed sighting of the seal was in 1952 in the Caribbean Sea at Serranilla Bank, between Jamaica and the Yucatán Peninsula.
“Humans left the Caribbean Monk Seal population unsustainable after overhunting them in the wild,” said Kyle Baker, biologist for NOAA’s Fisheries Service southeast region. “Unfortunately, this lead to their demise and labels the species as having gone extinct from human causes.”
There are several records throughout the colonial period of these seals being discovered and hunted at Guadelupe, the Alacrane Islands, the Bahamas, the Pedro Cays, and Cuba, Alto Velo, dry Tortugas Islands. As early as 1688 sugar plantations owners sent out hunting parties to kill hundreds of seals every night in order to obtain oil to lubricate the plantations machinery. A 1707 account describes fisherman slaughtering seals by the hundreds for oil to fuel their lamps. By 1850 so many seals had been killed that there were no longer sufficient numbers for them to be commercially hunted.
The extinction of the Caribbean Monk Seal was brought about by two main causes. The most visible factor contributing to the seals’ extinction was the nonstop hunting and killing of the seals in the 18th and 19th centuries to obtain the oil held within their blubber. The insatiable demand for seal products in the Caribbean encouraged hunters to slaughter these seals by the hundreds. The seals’ docile nature and lack of flight instinct in the presence of humans made it very easy for anyone to kill them.
The second factor was the overfishing of the reefs that sustained the seal population. With no fish or mollusks to feed on, the seals that were not killed by hunters for oil died of starvation or did not reproduce as a result of an absence of food. Not surprisingly little was done to try to save the Caribbean Monk Seal. By the time it was placed on the endangered species list in 1967 it was likely already extinct.
The Caribbean monk seal appears to be the only pinniped species that has become extinct in modern times so far. The reason for the extinction would seem to be quite obvious: they were mindlessly slaughtered in large numbers by European hunters, by plantation settlers and even by so-called scientists from the 17th to the 19th centuries. They were also persecuted and deliberately killed by native fishermen as these also expanded their range of activity to all parts of the seals’ habitat range. During the nursing period they were particularly vulnerable to hunters. Right up until the point of inevitable extinction in the mid to late 20th century humans had remained hostile to them, with apparently no attempt at conservation measures or protected areas. The political will was not present then and is still not present now.
Humans sought out and overkilled the Caribbean Monk Seals at all stages of their life cycle whilst at the same time overfishing the waters the seals depended on for their food. With no ability to reproduce in sufficient numbers and their food sources depleted, the seals were doomed to extinction and so it was. Now they are gone forever.