Kawakawa

Max length : 100.0 cm FL male/unsexed; common length : 60.0 cm FL male/unsexed; max. published weight: 14.0 kg

Family	Scombridae
Description	Mackerels, tunas, bonitos
Environment	Brackish & Marine
Etymology	Latin, scomber = mackerel.
Genus	15
No. of Species	54
Order	Perciformes
Class	Actinopterygii
Reproductive Guild	Nonguarders
Distribution	Tropical and subtropical seas. Body elongate and fusiform, moderately compressed in some genera. Snout pointed, premaxilla beaklike, free from nasal bones which are separated by the ethmoid bone; mouth large; teeth in jaws strong, moderate, or weak; no true canines; palate and tongue may bear teeth. The 2 dorsal fins separate and depressible into grooves with 5-12 finlets behind second dorsal and anal fins; first dorsal fin with 9-27 rays, origin well behind the head. Pectoral fins high on body. Pelvic fins moderate or small with 6 fin rays, placed below the pectoral fins. Caudal fin deeply forked with supporting caudal rays completely covering hypural plate. At least 2 small keels on each side of caudal fin base, a larger keel in between on caudal peduncle in more advanced species. Lateral line simple. Vertebrae 31-66. Body covered with small to moderate scales or a scaly corselet developed (area behind head and around pectoral fins covered with large thick scales) and rest of body naked or covered with tiny scales. Gill membranes not united to isthmus. Thunnus and close relatives with a specialized vascular system for heat exchange; the evolution of this and related adaptations for endothermy are discussed in Block et al. 1993 (Ref. 11221). Primarily swift, epipelagic predators; some species occur in coastal waters, others far from shore. Mackerels (Scomber and Rastrelliger) filter plankton with their long gill rakers. Spanish mackerels, bonitos and tunas feed on larger prey, including small fishes, crustaceans and squids. The main predators of smaller scombrids are other predacious fishes, particularly large tunas and billfises. Dioecious and most display little or no sexual dimorphism in structure or color pattern. Females of many species attain larger sizes than maels. Batch spawning of most species takes place in tropical and subtropical waters, frequently inshore. Eggs are pelagic and hatch into planktonic larvae. Among the most important of commercial and sport fishes. [Thunninae=ISSCAAP 36; Scombrinae=ISSCAAP 37]. Also Ref. 50681. According to the recent phylogenies (Ref. 58009), two subfamilies can be recognized: - Gasterochismatinae with one species Gasterochisma melampus. - Scombrinae: divided currently in four tribes (Ref. 58010), only Scombrini are supported by molecular data; more research is needed for Scomberomorini, Sardini, and Thunnini.

Occurs in open waters but always remains close to the shoreline. The young may enter bays and harbors. Forms multi-species schools by size with other scombrid species comprising from 100 to over 5,000 individuals. A highly opportunistic predator feeding indiscriminately on small fishes, especially on clupeoids and atherinids; also on squids, crustaceans and zooplankton

Dorsal spines (total): 10 - 15; Dorsal soft rays (total): 11-15; Anal spines: 0; Anal soft rays: 11 - 15; Vertebrae: 39. Swim bladder absent. No trace of vertebral protuberances. Anterior spines of first dorsal fin much higher than those mid-way. Interpelvic process small and bifid. Body naked except for corselet and lateral line. Posterior portion of the back with a pattern of broken oblique stripes.

Summary of Distribution: Indo-West Pacific: in warm waters including oceanic islands and archipelagos. A few stray specimens have been collected in the Eastern Central Pacific. Highly migratory species
Note: Distribution range colors indicate degree of suitability of habitat which can be interpreted as probabilities of occurrence (fishbase.org)