This is a list of the mammal species recorded in Trinidad and Tobago. These are the volant (flying) and terrestrial mammal species recorded for Trinidad and Tobago, and aquatic/marine species. Of these none are endangered and one is considered vulnerable. However, it is very important to note that many mammals are locally threatened in Trinidad and Tobago due mainly to heavy hunting and poaching, as well as habitat loss and fragmentation, with a number of species already having been extirpated on the island of Tobago. This list is derived from the IUCN Red List which lists species of mammals and includes those mammals that have recently been classified as extinct (since 1500 AD). The taxonomy and naming of the individual species is based on those used in existing Wikipedia articles as of 21 May 2007 and supplemented by the common names and taxonomy from the IUCN, Smithsonian Institution, or University of Michigan where no Wikipedia article was available.
Species found in Tobago are indicated in brackets after their name, in total there are 24 bats and 16 non-volant terrestrial mammals recorded for Tobago.
The following tags are used to highlight each species' conservation status as assessed by the International Union for Conservation of Nature:
| EX | Extinct | No reasonable doubt that the last individual has died. | |
| EW | Extinct in the wild | Known only to survive in captivity or as a naturalized populations well outside its previous range. | |
| CR | Critically endangered | The species is in imminent risk of extinction in the wild. | |
| EN | Endangered | The species is facing an extremely high risk of extinction in the wild. | |
| VU | Vulnerable | The species is facing a high risk of extinction in the wild. | |
| NT | Near threatened | The species does not meet any of the criteria that would categorise it as risking extinction but it is likely to do so in the future. | |
| LC | Least concern | There are no current identifiable risks to the species. | |
| DD | Data deficient | There is inadequate information to make an assessment of the risks to this species. |
Some species were assessed using an earlier set of criteria. Species assessed using this system have the following instead of near threatened and least concern categories:
| LR/cd | Lower risk/conservation dependent | Species which were the focus of conservation programmes and may have moved into a higher risk category if that programme was discontinued. | |
| LR/nt | Lower risk/near threatened | Species which are close to being classified as vulnerable but are not the subject of conservation programmes. | |
| LR/lc | Lower risk/least concern | Species for which there are no identifiable risks. |
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Didelphimorphia is the order of common opossums of the Western Hemisphere. Opossums probably diverged from the basic South American marsupials in the late Cretaceous or early Paleocene. They are small to medium-sized marsupials, about the size of a large house cat, with a long snout and prehensile tail.
----Sirenia is an order of fully aquatic, herbivorous mammals that inhabit rivers, estuaries, coastal marine waters, swamps, and marine wetlands. All four species are endangered.
----The armadillos are small mammals with a bony armored shell. They are native to the Americas. There are around 20 extant species.
----The order Pilosa is extant only in the Americas and includes the anteaters, sloths, and tamanduas.
----The order Primates contains humans and their closest relatives: lemurs, lorisoids, tarsiers, monkeys, and apes.
----Rodents make up the largest order of mammals, with over 40% of mammalian species. They have two incisors in the upper and lower jaw which grow continually and must be kept short by gnawing. Most rodents are small though the capybara can weigh up to 45kg (99lb).
----The bats' most distinguishing feature is that their forelimbs are developed as wings, making them the only mammals capable of flight. Bat species account for about 20% of all mammals.
----The order Cetacea includes whales, dolphins and porpoises. They are the mammals most fully adapted to aquatic life with a spindle-shaped nearly hairless body, protected by a thick layer of blubber, and forelimbs and tail modified to provide propulsion underwater.
Trinidad and Tobago is within the worldwide ranges of twenty eight cetacean species. Nineteen of these cetacean species have been recorded in Trinidad and Tobago waters and it is expected that more species will be recorded as cetacean research progresses in this area.[1]
----There are over 260 species of carnivorans, the majority of which feed primarily on meat. They have a characteristic skull shape and dentition.
----The even-toed ungulates are ungulates whose weight is borne about equally by the third and fourth toes, rather than mostly or entirely by the third as in perissodactyls. There are about 220 artiodactyl species, including many that are of great economic importance to humans.