Pacific Crevalle Jack

The Pacific crevalle jack is a relatively large fish, growing to a maximum recorded size of 101.6 cm in length and 19.7 kg in weight. It is similar to most other jacks of the genus Caranx, having a moderately deep and compressed, oblong body, with the dorsal profile more convex than the ventral profile, particularly anteriorly. The dorsal fin is in two distinct sections; the first consisting of eight spine and the second of one spine and 19 to 21 soft rays. The anal fin consists of two anteriorly detached spines followed by one spine and 16 to 17 soft rays. The pectoral fins are falcate, and consist of 19 to 21 soft rays, while the caudal fin is strongly forked. The species lateral line is moderately arched anteriorly, with 58 to 79 scales in this section, while the straight section contains none to seven scales and 34 to 43 strong scutes. The breast is devoid of scales with the exception of a small patch of scales in front of the pelvic fins. The species has well-developed adipose eyelids, while its dentition consists of an outer row of widely spaced canine teeth and an inner band of villiform teeth in the upper jaw, with a row of widely spaced conical teeth on the lower jaw. The Pacific crevalle jack has 21 to 27 gill rakers and 24 vertebrae. There are significant differences in the development of hyperostosis between this species and C. …

The Pacific crevalle jack inhabits the tropical to subtropical waters of the eastern Pacific Ocean. The species ranges along the western American coastline from Lobos de Tierra Island, Peru in the south and north to San Diego Bay, California. The species is generally rare north of the Gulf of California, however El Nino events which bring warm tropical waters further north than usual transport Pacific crevalle jack and other species beyond their normal range. All occurrences of the species in San Diego Bay have been attributed El Nino events in that year. The species is also known from several offshore Pacific islands including the Galápagos, Malpelo, Cocos, and Revillagigedo Islands. The Pacific crevalle jack is most common in coastal regions, although is occasionally found in more pelagic settings, with the species not known to live deeper than 350 m. In coastal waters the species prefers sandy and rocky substrates, including protected bays, lagoons and harbours, where large schools of the species form. Larger individuals are often solitary, and living in deeper offshore environments. Pacific crevalle jack are also common in estuaries, usually as juveniles which preferentially inhabit these environments, but also as adults that make their way into brackish waters and tidal streams. Juveniles are known to penetrate well upstream, indicating a wide salinity tolerance.