Spinner Dolphins-Entertainers of the Sea

As far as dolphins are concerned in this part of the world, it is usually the Bottlenose that garners most of the attention. However, another species that is often considered more fascinating and exciting to witness, also inhabits the waters off of Ambergris Caye. Spinner dolphins are not altogether common to this area, but recently Green Reef received a report from a fisherman who observed a pod of six or more dolphins swimming outside of the reef. This fortunate fisherman was treated to a show of twirls and flips from these elusive, yet highly social creatures.

    True to their name, Spinner dolphins are distinguished from other dolphins in their ability to leap out of the water and twist their bodies into elegant curves and spins. It is not known why they choose to do this, but some scientists believe this is one of many forms of communication these dolphins use. Additionally, Spinner dolphins have evolved a technique known as echolocation, in which pulses and clicks are sent out from the dolphin. As these sounds bounce off of an object, they are able to communicate with other dolphins or find prey. Using this technique, these extremely intelligent creatures are able to interpret the direction, distance, and size of potential prey, such as fish or squid.

    Spinner dolphins are found in tropical and subtropical waters worldwide and sightings occur in both offshore and inshore waters. These dolphins are known to prefer waters near islands that are adjacent to reefs, therefore it is no surprise they would find the area around Ambergris Caye an ideal habitat. Spinner dolphins often favor swimming over large sandy patches, presumably as a method of avoiding sharks that often hide in reef ridges. When they are not evading predators, these dolphins can be found during the day in shallow water either resting or playing. At night, however, Spinner dolphins become much more active and travel to deep water in search of food. This is also the time when these dolphins put on their greatest displays of spinning and flipping.

Reef Brief is a weekly column published in the San Pedro Sun

    In addition to the characteristic spinning of these dolphins, they are also identified by dark gray backs, light gray sides, and a light gray belly. These dolphins are streamlined and slender, on average growing to six feet and weighing up to 200 pounds. With long skinny beaks that are black on top and white below, Spinner dolphins are also equipped with flippers that are long and pointed. Like other dolphins, female Spinner dolphins reach sexual maturity at five to seven years of age, while the male matures later, at ages ten to twelve. Females give birth every two years and have an eleven-month gestation period. These dolphins may have a life span ranging anywhere from 30 to 40 years. Thus far, the worldwide population of Spinner dolphins is at a healthy level. The primary threat these dolphins face is in the Pacific Ocean, where by accident they are often caught in the nets  of yellowfish tuna fisheries. Conservationists have strongly opposed this fishing technique and have fought for alternative methods to be used, resulting in the advent of "dolphin-safe" tuna. Since there are no tuna fisheries in Belize, the only true threat this dolphin faces in our waters is pollution and habitat degradation due to increased coastal development. In order for us to continue enjoying these unique and amazing creatures, we must remain steadfast in their protection and the environment as a whole, so they can thrive in the clean and plentiful waters that this country is famous for.

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