Yellowfin tuna

The yellowfin tuna (Thunnus albacares), is a type of tuna. It is found in open waters of tropicalseas worldwide. It is an epipelagic fish ranging in the top 100 m (330 feet) of the water column. Reported sizes have ranged as high as 239 cm (94 inches) in length and 200 kg (440 lb) in weight. Also known as ahi tuna, from its Hawaiian name ʻahi, yellowfin is becoming a popular replacement for the severely depleted supplies of bluefin tuna. and subtropical

The second dorsal fin and the anal fin are both bright yellow, thus the common name, and can be very long in mature specimens, as are the pectoral fins. The main body is very dark metallic blue, changing to silver on the belly, which has about 20 vertical lines.

Yellowfins tend to school with fishes of the same size, including other species of tuna, and larger fish are often seen with dolphins, porpoises, whales and whale sharks. Yellowfins eat other fish, crustaceans, and squid.

from http://en.wikipedia.org/