Thunnini Near Taiwan Waters

Tuna are oceanic fishes, and one of the fastest swimmers in the ocean. They can go up to 75 miles per hour.

There are 15 species of tuna, belonging to the Thunnini subgroup of the Scombridae family. Here are some of the species you can find near Taiwan.

Scientific name: Thunnus orientalis
Common name: Pacific Bluefin Tuna
Max length: 3m
Max weight:300kg
Appearance:
Relatively small eyes compared to other species of tuna.
Black or dark blue dorsal sides, with a grayish-green iridescence.
Bellies dotted with silver or gray spots or bands.
Tips of the pectoral fins do not reach the front of the second dorsal fin.

Scientific name: Thunnus maccoyii
Common name: Southern Bluefin Tuna
Max length:: 245cm
Max published weight: 260kg
Appearance:
Pectoral fins short.
Main caudal keel dull yellow.
Finlets dull yellow with black edge.

Scientific name: Thunnus obesus
Common name: Bigeye Tuna
Max length: 250 cm TL male/unsexed
Max. published weight: 210.0 kg
Appearance:
Large eyes.
Stout body.
Pectoral fin tip pointed.
Finlets are bright yellow with black edges.

Scientific name: Thunnus albacares
Common name: Yellowfin Tuna
Common length : 150 cm FL male/unsexed
Max length : 239 cm FL male/unsexed;
Max. published weight:200kg
Appearance:
Metallic dark blue on the back and upper sides and change from yellow to silver on the belly.
Dorsal and anal fins are very long and bright yellow.

Scientific name: Thunnus alalunga
Common name: Albacore Tuna
Max length : 140 cm FL male/unsexed;
Max. published weight: 60.3 kg
Appearance:
Exceptionally long pectoral fins, which are at least half the length of their bodies.
The edge of the tail fin is white.

Scientific name: Thunnus tonggol
Common name: Longtail Tuna
Max length : 145 cm FL male/unsexed;
Max. published weight: 35.9 kg
Appearance:
Body slender, especially towards caudal fin.
Faint rows of colorless spots along belly.
Second dorsal fin is higher than the first.

Scientific name: Katsuwonus pelamis
Common name: Skipjack Tuna
Max length : 110 cm FL male/unsexed;
Max. published weight: 34.5 kg
Appearance:
Conspicuous dark bands that run from behind the head to the tail.

Source:
FishBase
Marine species identification manual for horizontal longline fisherman
https://www.fisheries.noaa.gov/
林富家陳文義(2008) 認識鮪魚類中的小兄弟-長腰鮪，水試專訊23期46-47