|
FAO Names |
 |
En - Southern bluefin tuna; Fr - Thon rouge du sud; Sp - at?n del sur. |
Size |
|
 Maximum fork length
is 225 cm (Yukinawa, 1970). In the Indian Ocean, common
sizes range between 160 to 200 cm fork length (Silas s
Pillai, 1982). The all-tackle angling record is a 158 kg
fish with a fork length of 203 cm taken off Whakatane,
New Zealand in 1981. Length-weight correlations vary,
particularly in adult fish in relation to physiological
condition. A 180 cm long southern bluefin tuna may have a
gutted weight of roughly 102 to 134 kg. Length at first
maturity is estimated by circumstancial evidence at 130
cm, equivalent to about 40 kg of weight. |
| Diagnostic Features | |
 A very large species,
deepest near middle of first dorsal fin base. Gillrakers
31 to 40 on first arch. Pectoral fins very short, less
than 80% of head length (or between 20.2 and 23% of fork
length), never reaching the interspace between the dorsal
fins. Ventral surface of liver striated. Swimbladder
present. Vertebrae 18 precaudal plus 21 caudal. Colour:
lower sides and belly silvery white with colourless
transverse lines alternated with rows of colourless dots
(the latter dominate in older fish), visible only in
fresh specimens; first dorsal fin yellow or bluish; anal
fin and finlets dusky yellow edged with black; median
caudal keel yellow in adults. |
| Geographical Distribution | |
 Probably found throughout the Southern Ocean south of 30? S. |
