Like most births of this type, the first few days of the larval yellowfin s life is critical. The larva lives off the egg of its yolk until its digestive system has developed to the point where it can hunt for food. The chances of the larval tuna surviving its first few weeks are not very promising. Some will simply starve to death , while the majority will be eaten by other fishes, sea birds, or their cannibalistic relatives. This can be evidenced by the fact that what little is known about the early development of yellowfins is by the examination of the contents of larger fishes stomachs.
Yellowfins grow quickly, attaining the weight of eight pounds by their first birthday.
These young tuna congregate with survivors of other spawnings and form protective schools until they are about four years old and weigh one hundred and forty pounds. Then, for some unknown reason, they abandon the school and become solitary swimmers for the rest of their lives, which can last for an additional fifteen years. The yellowfin inhabit vast areas of the earth s ocean. They are warm-water fishes and are usually found in waters with temperatures between 60 and 80 degrees Fahrenheit. Hence, its range extends from point conception southward, through the Gulf of California and along the Mexican Coast to the Galapagos.