Bigeye Tuna

Bigeye tuna

Scientific name

Thunnus obesus


Bigeye Tuna are a member of the family Scombridae and are easily distinguished by their noticeably larger eyes, hence the name. They have moderately long pectoral fins and yellow dorsal and anal fins.


Bigeye Tuna can reach a maximum size of 2.36 m and 210 kg in weight, however it is rare for these tuna to exceed 1.80 m in length and 150 kg in Australian waters.


Bigeye Tuna (or bigeye) are oceanic fish present throughout Australian waters. Geographic distribution is limited by temperature and oxygen concentrations. They have a greater tolerance to lower temperature and oxygen levels than other tunas, therefore, they tend to occupy deeper waters. They are generally found in more southern waters of Australia's east and west coasts, preferring offshore areas.

Confusing Species

Juvenile Bigeye Tuna are often confused with Yellowfin Tuna of the same size, however, the size of the eye and length of the anal fin separates these species.