Wahoo / Toson
Document Actions
Wahoo / Toson
Acanthocybium solandri
Image from Coral Reefs CD
The wahoo, or toson as it is called in Chamoru, is a member of the same family as tunas. It occurs in all tropical and warm-temperate seas where the water is 71°F (21°C) or warmer. They are among the fastest fishes known, able to reach speeds as high as 47 miles per hour (76 kph). They feed primarily on fishes and to a lesser extent, on squids and crustaceans. In coastal waters they feed largely on post-larval reef fishes and baitfish as well as on flying fishes and small tunas.
Tosun have extremely sharp close-set teeth that form a saw-like cutting edge. Their prey are frequently cleanly cut into two or three pieces. Their snapping jaws can be quite dangerous to the careless fisherman. Tosun are often found above deep drop-offs between the 140 to 660 foot(43 to 200 m) depth contours.
In the Atlantic and probably also on Guam, tosun spawn in the spring and summer. Little is known of their growth rates or migratory patterns. They reach a fork length of six feet 11 inches (2.1 m; measured from the tip of the snout to the notch in the middle of the tail) and weight of 150 pounds (68 kg). However, the largest ones caught near Guam are about 70 pounds (32 kg).
Tosun are not abundant enough in open ocean waters to form the basis of a major fishery, but are important in the small boat subsistence or sport fisheries of many countries. They are caught primarily by trolling with lures or squid. Highest catches on Guam usually occur in November when large numbers of small fish migrate through our ocean area. Catches throughout the rest of the year are variable with recent annual landings ranging from 16 to 80 tons (15-73 MT).
Guam Comprehensive Wildlife Conservation Strategy, 9/27/2005
