Cold smoked tuna fillet. Yellowfin tuna is a mackerel-like, including all tuna species. Tuna is a warm-blooded fish and has red-colored fish meat. Yellowfin tuna has a cobalt blue to black back side with a characteristic long yellow belly and dorsal fin. Yellowfin tuna can reach a length of 230 cm with a weight of 180 kg. The Yellowfin tuna swim to a depth of 250 meters, has a lot of power and can reach a speed of 80 km per hour. It is striking that the tuna does not have a swimming bladder which would cause it to sink like a brick when it stops swimming. That is why the tuna is constantly moving. Yellowfin tuna is a very fast growing fish and can reach an age of 9 years. High-quality tuna can be found in Panama, Mexico to California and Hawaii.