Some researchers believe that all seals evolved in tropical waters where only 2 species survive: Hawaiian monk seals and Mediterranean monk seals, both of which are critically endangered. Until the 1960's there was a third species in tropical waters-- Caribbean monk seals. Today it is unknown whether this animal still exists.
In 1493, during his famous voyage to the Americas, Columbus discovered the Caribbean monk seal. He called this creature a "sea-wolf." Because of its long isolation in the Caribbean and on the islands there, the species did not have the characteristic suspiciousness displayed by most seals. It was easily killed for its blubber and meat. Once fishermen began to colonize what little habitat M. tropicalis had left, the remaining population suffered a loss.
Recently, two scientific crews set out to find M. tropicalis around Jamaica and Haiti. Air surveys and personal interviews took place with fishermen in the area. About 23% stated they had seen a monk seal this, or last year. Because there are only 3 tropical species of seal, separated by oceans, it is believed that these sightings indicate the presence of Caribbean monk seals. However, because of expanded commercial and sustenance fishing, it is unlikely that these seals have been able to survive. Undisturbed habitat is necessary to meet the requirements of this animal, and in this area such habitat is very limited. Unconfirmed sightings of monk seals in their native range are probably of wandering hooded seals (Cystophora cristata), which have been confirmed near Puerto Rico and the Virgin Islands.
Caribbean monk seals had relatively few predators. It is likely that the biggest threats to them (other than humans) were the sharks. Although they were agile swimmers, these seals were not able to move quickly while on land. Bbecause of their isolated evolutionary history, M. tropicalis was not equipped with an innate fear of predation on land. This made them relatively easy targets for pioneers and fishermen.
Known Predators:
Caribbean monk seals were known to be beautiful animals. They had brown pelage, lightly frosted with gray, fading to a pale yellow on the stomach. They had hoodlike rolls of fat that surround their necks. Their hair was very short and stiff. The nails on the anterior digits were well developed, and nails on the posterior digits were simple. Their soles and palms were naked. They have also had 4, rather than 2 mammary glands. Their dental formula was 2/1, 1/1, 5/5. It is likely that there was sexual dimorphism, with males reaching up to 200 kg in some accounts. Females were likely smaller, ranging from 70-140 kg, although there is disparity in records. Infants were born with coal-black pelage.
Range mass: 70 to 200 kg.
Range length: 220 to 240 cm.
Average length: 222.50 cm.
Other Physical Features: endothermic ; homoiothermic; bilateral symmetry
Sexual Dimorphism: male larger
Actual lifespan of M. tropicalis is unknown. However it is believed the average life span was around 20 years.
Average lifespan
Status: wild: 20 years.
Little is known about the habitat of M. tropicalis. Likely, beach habitat was important, however they spent much of their time in the water. Caribbean monk seals occupied a marine environment, with rocky or sandy coastline for shelter and breeding areas. Unconfirmed sightings of M. tropicalis by divers usually take place underwater. This suggests they are rarely seen at the surface, or when they are, they are rarely recognized. Recent evidence indicates the ultimate contributing factor to the decline of Caribbean monk seals was loss of habitat.
Habitat Regions: temperate ; tropical ; saltwater or marine
Aquatic Biomes: reef ; coastal
Monachus tropicalis has officially been declared extinct. Historically, the range of Caribbean monk seals was in the tropical waters of the Florida Keys, the Bahamas, the Greater and Lesser Antillies, around the Yucatan Penninsula, and around offshore islets and atolls. Currently, unconfirmed sightings are most common in Northern Haiti and North-east Jamaica. It is the only pinniped ever known to exist in the Caribbean region. The last recorded sighting of M. tropicalis in the United States was in 1932 off the coast of Texas and a small group was sighted on Seranilla Bank, between Honduras and Jamaica, in 1952.
Biogeographic Regions: nearctic (Native ); neotropical (Native ); atlantic ocean (Native )
Because Caribbean monk seals were classified as extinct before it was possible to study them, their primary diet is not known to science. It is assumed however, that it followed the typical monk seal diet of fishes and invertebrates. Caribbean monk seals are also assumed to have preyed on pelagic species, along with spiny lobsters, eels, octopus, and various other reef fish.
Animal Foods: fish; mollusks; aquatic crustaceans
Primary Diet: carnivore (Piscivore , Eats non-insect arthropods, Molluscivore )
The exact role this species played in the Caribbean ecosystem is unknown. As predators, they probably had some affect on regulating local fish populations.
Christopher Columbus was the first to note this species in his accounts. With the arrival of other Europeans, M. tropicalis was relentlessly exploited for the commercially valuable oil produced from their blubber. It was also used, less commonly, for meat.
Positive Impacts: food
It was believed that M. tropicalis was a competitor to the fishing industry. This belief inspired mass killings of M. tropicalis by fishermen.
It is believed that M. tropicalis is now extinct. Although there are unconfirmed sightings still in Caribbean areas, two expeditions in search of M. tropicalis failed to produce any evidence that M.tropicalis is still present in these waters.
US Federal List: endangered
CITES: appendix i
IUCN Red List of Threatened Species: extinct
Perception Channels: tactile ; chemical
The mating system of these seals is unknown.
Very little is known about the reproductive behavior of M. tropicalis. Births were likely in early December because several females killed in the Triangle Keys during this time had well-developed fetuses. One young per female is thought to have been born.
Breeding season: Births were likely to occur in early December.
Average number of offspring: 1.
Key Reproductive Features: iteroparous ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; viviparous
Little is known of the parental care of Caribbean monk seals. The nursing period is likely to have been relatively short, because the mother did not feed between birth and weaning. It is unknown what role, if any, male parental care played.
Parental Investment: precocial ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female)
A comprehensive summary of what we know of this extinct species
The Caribbean monk seal (Neomonachus tropicalis), also known as the West Indian seal or sea wolf, was a species of seal native to the Caribbean which is now believed to be extinct. The main predators of Caribbean monk seals were sharks and humans.[3] Overhunting of the seals for oil and overfishing of their food sources are the established reasons for the seals' extinction.[3]
The last confirmed sighting of the Caribbean monk seal was in 1952 at Serranilla Bank, between Jamaica and Nicaragua.[4] In 2008, the species was officially declared extinct by the United States, after an exhaustive five-year search. This analysis was conducted by the National Marine Fisheries Service of the National Oceanic and Atmospheric Administration.[5] Caribbean monk seals were closely related to Hawaiian monk seals, which live around the Hawaiian Islands and are now endangered, and Mediterranean monk seals, another endangered species.[6][7]
Caribbean monk seals had a relatively large, long, robust body, could grow to nearly 2.4 metres (8 ft) in length and weighed 170 to 270 kilograms (375 to 600 lb). Males were probably slightly larger than females, which is similar to Mediterranean monk seals. Like other monk seals, this species had a distinctive head and face. The head was rounded with an extended broad muzzle. The face had relatively large wide-spaced eyes, upward opening nostrils, and fairly big whisker pads with long light-colored and smooth whiskers. When compared to the body, the animal's foreflippers were relatively short with little claws and the hindflippers were slender. Their coloration was brownish and/or grayish, with the underside lighter than the dorsal area. Adults were darker than the more paler and yellowish younger seals. Caribbean monk seals were also known to have algae growing on their pelage, giving them a slightly greenish appearance, which is similar to Hawaiian monk seals.[8]
Historical records suggest that this species may have "hauled out" at resting areas on land in large social groups, typically 20–40 animals, but sometimes up to 100 individuals, throughout its range.[9] The groups may have been organised based on age and life stage differences. Their diet most likely consisted of fish and crustaceans.
Like other true seals, the Caribbean monk seal was sluggish on land. Its lack of fear of humans, and an unaggressive, curious nature was taken advantage of by human hunters.
Caribbean monk seals had a long pupping season, which is typical for pinnipeds living in subtropical and tropical habitats. In Mexico, breeding season peaked in early December. Like other monk seals, this species had four retractable nipples for suckling their young. Newborn pups were probably about 1 metre (3 ft 3 in) in length and weighed 16 to 18 kilograms (35 to 40 lb) and reportedly had a sleek, black lanugo coat when born.[9] It is believed this animal's average lifespan was approximately twenty years.
The Caribbean monk seal nasal mite (Halarachne americana), was entirely dependent on the seal, living inside of its nasal cavity, and went extinct with it.
Caribbean monk seals were found in warm temperate, subtropical and tropical waters of the Caribbean Sea, Gulf of Mexico, and the western Atlantic Ocean. They probably preferred to haul out at low sandy beaches above high tide on isolated and secluded atolls and islands, but occasionally would visit the mainland coasts and deeper waters offshore. This species may have fed in shallow lagoons and reefs.[8]
The first historical mention of the Caribbean monk seal is recorded in the account of the second voyage of Christopher Columbus. In August 1494, a ship laid anchor off the mostly barren island of Alta Velo, south of Hispaniola, where the party of men aboard killed eight seals that were resting on the beach.[10] The second recorded interaction with Caribbean monk seals was Juan Ponce de León's discovery of the Dry Tortugas Islands. On June 21, 1513, when Ponce de León discovered the islands, he ordered a foraging party to go ashore, where the men killed fourteen of the docile seals.[11] There are several more records throughout the colonial period of seals being discovered and hunted at Guadeloupe, the Alacrane Islands, Bahamas, Pedro Cays, and Cuba.[3] As early as 1688, sugar plantation owners sent out hunting parties to kill hundreds of seals every night in order to obtain oil to lubricate the plantation machinery.[12] A 1707 account describes fisherman slaughtering seals by the hundreds for oil to fuel their lamps.[3] By 1850, so many seals had been killed that there were no longer sufficient numbers for them to be commercially hunted.[12]
In the late 19th and early 20th centuries, scientific expeditions to the Caribbean encountered the Caribbean monk seal. In December 1886, the first recorded scientific expedition to research seals, led by H. A. Ward and Professor F. Ferrari Perez as part of the Mexican Geographical and Exploring Survey, ventured to a small collection of reefs and a small cay known as the Triangles (20.95° N 92.23° W) in search of monk seals.[13] Although the research expedition was in the area for only four days, forty-two specimens were killed and taken away; the two leaders of the expedition sent to museums around the Western world.[13] Two specimens from the encounter survive intact at the British Museum of Natural History, and the Cambridge Zoological Museum, respectively.[3] The expedition also captured a newly born seal pup that died in captivity a week later.[13]
The first Caribbean monk seal to live in captivity for an extended period was a female seal that lived in the New York Aquarium.[14] The seal was captured in 1897 and died in 1903, living in captivity for a total of five and a half years.[14] In 1909, the New York Aquarium acquired four Caribbean monk seals, three of which were yearlings (between one and two years old) and the other a mature male.[15]
Through 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.[11] Fishermen captured six seals in 1915, which were sent to Pensacola, Florida, and eventually released.[16] A seal was killed near Key West, Florida in March 1922.[17] There were sightings of Caribbean monk seals on the Texas coast in 1926 and 1932.[18] The last seal recorded to be killed by humans was killed on the Pedro Cays in 1939.[19] Two more seals were seen on Drunken Mans Cay, just south of Kingston, Jamaica, in November 1949.[3] In 1952 the Caribbean monk seal was confirmed sighted for the last time at Serranilla Bank, Colombia.[4]
The final extinction of the Caribbean monk seal was triggered by two main factors. The most visible factor contributing to the Caribbean monk seals' demise was the nonstop hunting and killing of the seals in the 18th and 19th centuries to obtain the oil held within their blubber.[20] The insatiable demand for seal products in the Caribbean encouraged hunters to slaughter the Caribbean monk seals by the hundreds.[21] The Caribbean monk seals' docile nature and lack of flight instinct in the presence of humans made them very easy to kill.[13] The second factor was the overfishing of the reefs that sustained the Caribbean monk seal population. With no fish or mollusks to feed on, the seals that were not killed by hunters for oil died of starvation.[22] Surprisingly few conservation measures were taken towards attempting to save the Caribbean monk seal; by the time it was placed on the endangered species list in 1967, it was likely already extinct.[20]
Unconfirmed sightings of Caribbean monk seals by local fishermen and divers are relatively common in Haiti and Jamaica, but two recent scientific expeditions failed to find any sign of the species. It is possible the mammal is still extant, but some biologists strongly believe the sightings are of wandering hooded seals, which have been positively identified on Caribbean archipelagos such as Puerto Rico and the Virgin Islands.[23][24]
{{cite journal}}: Cite journal requires |journal= (help) The Caribbean monk seal (Neomonachus tropicalis), also known as the West Indian seal or sea wolf, was a species of seal native to the Caribbean which is now believed to be extinct. The main predators of Caribbean monk seals were sharks and humans. Overhunting of the seals for oil and overfishing of their food sources are the established reasons for the seals' extinction.
The last confirmed sighting of the Caribbean monk seal was in 1952 at Serranilla Bank, between Jamaica and Nicaragua. In 2008, the species was officially declared extinct by the United States, after an exhaustive five-year search. This analysis was conducted by the National Marine Fisheries Service of the National Oceanic and Atmospheric Administration. Caribbean monk seals were closely related to Hawaiian monk seals, which live around the Hawaiian Islands and are now endangered, and Mediterranean monk seals, another endangered species.
