Overview
It is noted for its lack of scales (except on the corselet and along either side of the lateral line) and for its large conical teeth; features which have given it the names “scaleless tuna” and “dogtooth tuna” respectively. It is actually a bonito. The first dorsal fin has 13 15 spines, the second is higher and has 12 14 rays followed by 6 7 dorsal finlets. The anal fin has 12 13 rays. There are 11 14 gill rakers on the first arch. The lateral line is prominent and wavy, ending in a keel on the caudal peduncle. It is the only bonito that has a swim bladder and a large, single interpelvic process. There are no dark stripes or spots on the body. The second dorsal and anal fins are tipped with white.
Taxonomy
- Kingdom
- Animalia
- Phylum
- Chordata
- Class
- Actinopterygii
- Order
- Pleuronectiformes
- Family
- Scombridae
- Genus
- Gymnosarda
- Species
- unicolor
Habitat
Inhabits tropical and subtropical areas of the Indian and western Pacific Oceans around coral reefs. It has been taken in the Red Sea and sporadically in southern Japanese waters as well as around Papua New Guinea, the Marshall Islands, the Society Islands, the Marquesas Islands and from East Africa to Australia. It is a pelagic and migratory species, but is known to enter in shore waters during the warm season. It is usually found around or reefs, channels, passes or rocky areas.
Diet
feeds extensively on reef fish. Tunas and most bonitos feed more often on pelagic, schooling fishes, but no tuna or bonito feeds exclusively on any one type of prey. The dogtooth will readily consume a smaller mackerel, squid or other pelagic fish.
Behavior
Dogtooth tuna are typically solitary or found in small groups, making them ambush predators that actively hunt during the day around reefs and structures. They exhibit aggressive feeding behavior, often striking bait with force, and are known for their migratory patterns following prey schools. They can be territorial around feeding areas, defending them from other predators.
Fishing
When hooked its first run is fast and long and is followed by a deep, circling, tough fight. It is usually taken incidentally while deep trolling or deep live or dead bait fishing for other species in the vicinity of an off shore reef, though some are caught on rigs trolled on or near the surface. It has been known to take mackerel, mullet, squid, strip baits, spoons, plugs, feathers and plastic lures. The dogtooth is reported to be excellent both as a sport fish and as table fare.
Conservation Status
Listed as Least Concern by IUCN.