Stenella coeruleoalba
striped dolphin

Stenella coeruleoalba is found in warm-temperate and tropical seas throughout the world. S. coeruleoalba has been observed in the Mediterranean Sea, eastern and western Pacific Ocean, Atlantic Ocean, Indian Ocean, Caribbean Sea, and in the northern Gulf of Mexico (Baird et. al., 1993; Archer and Perrin, 1999).

Striped dolphins occupy both offshore and inshore warm-temperate and tropical waters. S. coeruleoalba appears to avoid sea surface temperatures of less than 20 degrees C (Van Waerebeek et. al., 1998).

Stenella coeruleoalba, otherwise known as striped dolphins, are a fascinating member of the family Delphinidae. S. coeruleoalba ranges in body length from 220cm to 236cm. Like many other delphinids, striped dolphins have a fusiform body, tall dorsal fins, long, narrow flippers, and a prominent beak (Archer and Perrin, 1999). S. coeruleoalba can be identified from other delphinids by their distinctive color and stripe patterns. Striped dolphins are typically bluish-gray in color with a dark dorsal cape and light (usually white) ventral coloration. They are called 'striped' dolphins because of the dark bluish-black stripe running across the entire length of the body, from the eye to the anus, and because they possess black flipper stripes (Archer and Perrin, 1999).

Group size in S. coeruleoalba ranges from a few individuals to over one-thousand individuals, but most schools consist of 100-500 dolphins. Three different kinds of schools often occur: juvenile, breeding adults, and non-breeding adults. Calves do not usually join the juvenile school until one or two years after weaning (Archer and Perrin, 1999). As females reach the transition stage between juvenile and adult, they usually join the non-breeding adults, only a small number go straight to the breeding school. However, as males join an adult group, equal numbers tend to join the breeding and non-breeding schools (Archer and Perrin, 1999).

Striped dolphins are very active, performing aerial maneuvers such as breaching (jumping out of the water), chin slaps, bow-riding (swimming along the wave created by a boat or ship, while often twisting and jumping) and a unique behavior called "roto-tailing," in which "they make high arcing jumps while violently and rapidly performing several rotations with the tail before reentering the water" (Archer and Perrin, 1999).

Like other delphinids, striped dolphins often vocalize with clicks and whistles, which presumably function in communication.

S. coeruleoalba seems to have an opportunistic feeding habit. Examining the stomach contents of many striped dolphins, researchers have found S. coeruleoalba to mainly feed on cephalopods, crustaceans, and bony fishes (Wuertz and Marrale, 1993). There is some variation in diet between ranges of S. coeruleoalba. Mediterranean striped dolphins seem to prey primarily on cephalopods (50-100% of stomach contents), while northeastern Atlantic striped dolphins most often prey on fish, frequently cod (Archer and Perrin, 1999). The ranges of observed prey indicate that striped dolphins primarily feed in pelagic or benthopelagic zones of the ocean, often along the continental slope (at the edge of the continental shelf where the ocean floor plunges steeply four to five kilometers) (Archer and Perrin, 1999).

Striped dolphins are in constant competition with humans over prey. The dolphins and fisheries compete over anchovies, tuna, and cod. Fisherman often kill striped dolphins that are caught in their fishing nets. The number of striped dolphins killed in the western Pacific was estimated at 14,000 each year between 1950-1969, but more recently has decreased to between 2,000 and 4,000 per year (http://www.cetacea.org/striped.htm, 1998).

Striped dolphins provide much entertainment to sailors and travelers, as they flip, twist, and breach alongside the waves created by ships and boats. In addition, they are sometimes hunted for meat.

S. coeruleoalba is currently listed at Lower Risk in the IUCN - Red List. It is further categorized as being "Conservation Dependent," meaning that the species is in a taxa that is the focus of a conservation program. Without a conservation program, the striped dolphin will qualify for a threatened/endangered status within five years.

Habitat degradation, commercial fisheries, and killing dolphins for their meat all contribute to striped dolphin population declines.

'/Stenella coeruleoalba/' is derived from the Latin "caeruleus" (sky-blue) and "albus" (white).

Some striped dolphins have been held in captivity, but have not been successfully trained.

(http://www.cetacea.org/striped.htm, 1998)