Pantropical Spotted Dolphin

The pantropical spotted dolphin varies significantly in size and coloration throughout its range. The most significant division is between coastal and pelagic varieties. The coastal form is larger and more spotted. (These two forms have been divided into subspecies only in eastern Pacific populations). Spots are key defining characteristics in adults, though immature individuals are generally uniformly colored and susceptible to confusion with the bottlenose dolphin. Populations around the Gulf of Mexico may be relatively spot-free even in adulthood. In the Atlantic, confusion is possible with the Atlantic spotted dolphin. The pantropical spotted dolphin is a fairly slender, streamlined animal, with a dark cape and light spots on its body that increase in number and size as it gets older. This species has a long, thin beak and a falcate dorsal fin, which is the thinnest among dolphins. The upper and lower jaws are darkly colored, but are separated by thin, white "lips". The chin, throat, and belly are white to pale grey with a limited number of spots. The flanks are separated into three distinct bands of color — the lightest at the bottom, followed by a thin, grey strip in the middle of the flank, and a dark-grey back. The tall concave dorsal fin is similarly colored. …

The pantropical spotted dolphin, as its name implies, is widely distributed around tropical and marine waters from 40°N and 40°S and is one of the most common dolphin species in the Atlantic and Indian oceans. The total world population is in excess of three million — the second-most abundant cetacean after the bottlenose dolphin — of which two million are found in the eastern Pacific. However, this represents a decrease from at least 7 million since the 1950s. The pantropical spotted dolphin is the most common cetacean species observed within the Agoa Sanctuary, located in the Lesser Antilles in the eastern Caribbean. Because it is common within the sanctuary it is considered a resident species; however, no research has been carried out to estimate its population status and movement patterns between islands. Centres of highest population density are the shallow warmest waters (water temperature in excess of 25 °C). They also tend to concentrate where a high temperature gradient is found.