Stenella
Stenella is a genus of oceanic dolphins found in tropical and subtropical waters worldwide. They are characterized by their slender bodies, long beaks, and relatively small dorsal fins. Stenella dolphins are highly social animals and often form large pods, sometimes numbering in the hundreds. They are known for their acrobatic displays, leaping and spinning in the water.
Common Names
Species within the genus Stenella are commonly known as:
- Spotted dolphins
- Striped dolphins
- Spinner dolphins
Characteristics
Stenella dolphins are generally slender, with long, pointed beaks. Their dorsal fins are relatively small and falcate (curved). They have a distinct color pattern, with a dark back, lighter sides, and a white belly. Some species, such as the spotted dolphin, have distinctive spots or stripes. Adults of most species reach a length of 1.5 to 2.5 meters and weigh between 50 and 150 kilograms. They can live for 20 to 30 years in the wild.
Environment
Stenella dolphins are found in all tropical and subtropical oceans, but they prefer warm waters. They are often found in areas with high productivity, such as upwelling zones and areas where there are large schools of fish. They are pelagic, meaning they inhabit the open ocean, often far from land.
Diet
Stenella dolphins are primarily piscivores, feeding on a variety of fish, squid, and crustaceans. They use echolocation to locate prey, emitting sound waves and interpreting the echoes that bounce back. They are also known to engage in cooperative feeding, working together to herd fish into tight schools.
Reproduction
Stenella dolphins are sexually mature at around 5 to 7 years of age. They breed throughout the year, with gestation lasting about 11 to 12 months. Calves are born tail-first and are dependent on their mothers for milk and protection for the first year or two of life.
Conservation
Several species of Stenella dolphins are listed as threatened or endangered by the International Union for Conservation of Nature (IUCN). Threats include habitat loss, bycatch in fisheries, and pollution. Conservation efforts focus on reducing bycatch, protecting critical habitat, and raising public awareness about the importance of these animals.