Classification: 

The Pantropical spotted dolphin is the species of dolphin known for its persecution in the eastern tropical Pacific tuna-fisheries.

Millions of dolphins have been killed as a result of the practice of 'setting nets' on the dolphins to catch the tuna below.

 Two subspecies of pantropical spotted dolphin are currently recognised, a coastal form S. a. attenuata, found in coastal waters of the eastern tropical Pacific, and an offshore form, S. a. graffmani found elsewhere in the range.

 

 

Appearance: 

The pantropical spotted dolphin is a medium sized, streamlined cetacean. Its falcate dorsal fin is pointed and very narrow and the small pointed flippers are dark on both sides.

It has a dark grey cape, extending mid-way down the flanks and sweeping up behind the dorsal fin. The sides and belly are a lighter grey colour.

As its name suggests, the body is covered with spots to a varying degree according to age and location with individuals in some areas having few to no spots.

The coastal subspecies is generally larger, more robust, with a thicker beak and more spots.

The lips and tip of the beak are white, and there is a dark stripe from the lower jaw to the flipper on both sides. Calves are born with no spots, and have a dark grey cape and very pale sides and belly.

Juveniles develop dark spots on the belly and lighter spots on the dorsal side and spotting continues to increase with age with fusing of the spots in older animals. 

 

 

Behaviour: 

Pantropical spotted dolphins are highly active and acrobatic, frequently performing high breaches and side-slaps.

They are fast swimmers, and perform long low leaps at high speeds.

They are known to bow and wake-ride in most parts of their range, although they generally avoid boats in the eastern tropical Pacific where they were persecuted for many years.

The coastal form tend to be found in groups of less than 100 individuals while groups of the offshore form can number in the thousands.

Pantropical spotted dolphins can often be seen associating with other species of oceanic dolphins and yellow-fin tuna, a behaviour that has historically been exploited by tuna fishermen.