The tucuxi dolphin, sotalia fluviatilis, is split into a freshwater and marine subspecies (although they do behave similarly for the most part). They measure 4.2 to 7.2 feet (1.3 to 2.2 meters) long and weigh 77 to 121 pounds (35 to 55 kilograms). Their backs are light grey to blueish-grey in color while their undersides are pinkish to light-grey. The lower jaw and throat will also have a pinkish coloration every now and then. They have a triangular, rounded and curved dorsal fin that is slightly hooked at the tip. Their beaks are long and slender with a rounded forehead and their upper and lower jaws both contain 26 to 36 pairs of teeth.
The tucuxi dolphin can be found in the river systems of both the Amazon and Orinoco as well as along the coasts from Brazil to Nicaragua. The freshwater subspecies will only inhabit freshwater bodies (such as lakes and rivers) while the marine subspecies will inhabit shallow, protected coastal estuaries and bays. They live in groups that can contain as many as 20 (freshwater) or 50 (marine) and they communicate with each other through the use of echolocation. This mammal tends to be most active during the early mornings and late afternoons. They are generally slow swimmers that jump infrequently and dive for up to 30 seconds at a time.
The diet of a tucuxi dolphin consists of many different fish (28 in fact), crustaceans, krill and even squids. They will use echolocation to help them search for food. If they detect something under the sea floor, they will use their beaks to clear the sand away and reveal their prey. A tucuxi dolphin doesn’t really have any natural predators, but humans will hunt them from time to time.
Not much is known about the mating behavior of the tucuxi dolphin. What is known about the freshwater subspecies is that they give birth to a single offspring (called a calf) from October to November after a gestation period of 11 to 12 months (putting their mating season at basically the same time of the year). Females are thought to have multiple partners when mating and males will become aggressive to other males for the right to mate. If the young calves can survive long enough, then they can live to be 30 (freshwater) and 35 (marine) years old.
It is currently unknown whether or not the tucuxi dolphin is an endangered species due to a lack of sufficient population numbers. They still however, face numerous threats such as habitat loss, pollution, accidental entanglement and occasional hunting. Hopefully, more information can be obtained on the tucuxi dolphin soon so that people know where this creature stands in terms of population and whether or not they need our protection. After all, such a unique marine mammal deserves to live and prosper far into the future.
Works Cited
“Tucuxi Dolphin (Sotalia Fluviatilis)” 2 January 2012
“Tucuxi” 2 January 2012
“Tucuxi” 2 January 2012