Mammals have conquered the various existing media, such as sea, air and land. In this article on our site we present an interesting article about one of the families of aquatic mammals, the Phocaenidae, commonly known as porpoises.
These animals are often confused with dolphins. However, both from the taxonomic and anatomical point of view, these animals present differences. Aspects such as size, reproductive habits and physical characteristics are some of the features in which these aquatic mammals differ.
We invite you to continue reading, in order to learn about the porpoises, their main characteristics, types and habitats.
What are porpoises?
Porpoises are aquatic mammals, belonging to the odontocetes within the group of cetaceans, which are provided with teeth. Likewise, they belong to the family Phocoenidae, where the smallest species of cetaceans are found.
Porpoises and dolphins are commonly confused due to their similar appearance, due to the fact that they share a good part of the taxonomic levels. However, both groups diverge in the final classification point, thus belonging to different families (Delphinidae for the latter and Phocoenidae for the former).
Characteristics of Porpoises
Porpoises are relatively small individuals, compared to other cetaceans. The size range can vary depending on the species between 1.5 to 2 meters in length, although individuals can be found below or above these measurements. As for the weight, it ranges from about 50 to 220 kg approximately.
There is sexual dimorphism in relation to the size of females, who are usually larger than males. The body is similar to a torpedo and they have a single spiracle or orifice associated with breathing.
Although the skull is somewhat similar to that of dolphins, it has certain protuberances that differentiate it. The facial form extends backwards, which gives the peculiar feature to the head, which results in a bulky structure, devoid of ears.
Their jaws are short, so they do not have the elongated shape that characterizes dolphins. They have numerous teeth, with the peculiarity that the end of the mouth does not completely cover the dental structures, which gives the impression thatthey are always smiling
With the exception of the genus Neophocaena, which lacks a dorsal fin, the rest do have this structure but tend to be small and triangular or pointed. They also have two fins forward, plus the tail. They are usually a uniform gray color, but there are also some with a marked gray, black and white coloration. On the other hand, their body is covered with a thick layer of fat that helps them with thermoregulation, in addition to serving in some cases as protection against predation.
Although their eyes are not that big in relation to their body size, they have good vision development. In addition, they have the sense of echolocation, which, as in other cetaceans, is highly developed, allowing them to locate themselves and learn about the surrounding environment, relying on the emission of high-frequency sounds known as clicks.
Types of Porpoises
There are three genera of porpoises, which contain a total of seven species. Let's find out what they are:
Genus Neophocaena:
Two species of porpoise are found here:
- Finless Porpoise (Neophocaena phocaenoides): is a species that lives in the East, in countries such as Bangladesh, Cambodia, India, Iran, Singapore, Thailand and the United Arab Emirates, among others. It is found in shallow waters of coasts, mangroves and estuaries. It is considered in vulnerable status
- Smooth porpoise (Neophocaena asiaeorientalis): This species is native to China, Japan, and the Republic of Korea. It inhabits coastal areas, mangroves and large rivers. It is classified as critically endangered.
Genus Phocoena:
It is the genus that groups the largest number of porpoise species, with a total of four:
- Harbor's porpoise (Phocoena phocoena): it has a wide distribution, occupying some regions in America, Europe and Asia. They are generally located in shallow coastal waters, estuaries, and certain channels. It is considered in the category of least concern.
- Vaquita marina (Phocoena sinus): This species of porpoise is endemic to Mexico and inhabits shallow and generally murky marine waters. It is classified as critically endangered.
- Spectacled Porpoise (Phocoena dioptrica): found in cold, temperate and subantarctic waters of the southern hemisphere, with sightings in countries such as Argentina, Australia, Brazil, Chile, Uruguay, among others. It is considered in the category of least concern.
- Black porpoise (Phocoena spinipinnis): its distribution range occupies Argentina, Brazil, Chile, Peru and Uruguay. It lives in shallow and coastal marine waters, but also in channels, areas of algae and is capable of diving to a depth of about 1000 m. It is considered in the category of near threatened
Genus Phocoenoides:
This genus includes a single species of porpoise:
