Cochito, Gulf of California harbour porpoise, Gulf of California porpoise, Gulf porpoise, Desert porpoise
Vaquitas (Phocoena sinus) are record-holders among all cetaceans. Thus, these animals are the smallest cetaceans, meanwhile being the smallest porpoises; they have the smallest range; and finally, vaquitas are the most critically endangered cetacean species in the world. ‘Vaquita’ is a Spanish word meaning "little cow". The scientific name of this animal means “porpoise of the gulf”, as this cetacean is endemic to Mexico. Vaquitas are a quite recently discovered species: they were first identified in 1958 based on skulls and were first observed in 1985.
The vaquita can be easily distinguished from any other species in its range. It has a small body with an unusually tall, triangular dorsal fin, a rounded head, and no distinguished beak. The coloration is mostly grey with a darker back and a white ventral field. Prominent black patches surround its lips and eyes. Mature females are typically longer than males and have larger heads and wider flippers.
Vaquitas inhabit the upper Gulf of California (also called the Sea of Cortez), making this the smallest range of any marine mammal species. They live in shallow, turbid waters of less than 150 m (490 ft) depth. Vaquitas live in murky warm waters within 16 miles (25.7 km) of the shoreline since there is high food availability and a strong tidal mix.
Vaquitas can be found solitarily, in pairs as well as in groups, consisting of up to 7 individuals. These shy and secretive animals do not tend to perform acrobatic maneuvers. When coming to the surface to breathe, they move slowly and are quite difficult to spot, barely disturbing the surface and diving back into the water. As common in cetaceans, these animals are known to use echolocation when looking for prey. However, some species of fish these cetaceans consume, give out specific sounds, suggesting that Vaquitas are likely to find them due to these sounds instead of using echolocation. They also use echolocation when communicating with conspecifics in areas with murky waters.
Vaquitas are carnivores (piscivores). Feeding at the water’s surface, this animal mainly consumes teleost fish, squid, and crustaceans.
Vaquitas are polygynous, which means that one male gets the exclusive right to mating with multiple females. They mate from mid-April to May and give birth to a single calf, usually in early March, after a gestation period of approximately 10-11 months. The newborn calf is nursed by its mother for 6-8 months, reaching sexual maturity at 3-6 years old.
Presently, the primary threat to this Critically Endangered species is commercial and artisanal fishing. These animals are known to become entangled in the gill nets and trawl nets, used by fisheries, which endanger the lives of 39-84 Vaquitas every year. In addition, because of the extremely small population, Vaquitas are threatened by interbreeding. Other notable concerns include environmental pollution and the degradation of their natural habitat.
According to the IUCN Red List, the total population of Vaquita includes less than 250 mature individuals. Currently, this species is classified as Critically Endangered (CR), and its numbers are decreasing.
