This is a list of the mammal species recorded in Puerto Rico. These are the mammal species in Puerto Rico, of which one is critically endangered, none are endangered, two are vulnerable, and none are near threatened. Two of the species listed for Puerto Rico are considered to be extinct.[1]
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. |
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.
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 45 kg (99 lb).
The order Primates includes the lemurs, monkeys, and apes, with the latter category including humans.
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.
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 – hoofed animals – which bear weight equally on two (an even number) of their five toes: the third and fourth. The other three toes are either present, absent, vestigial, or pointing posteriorly.
