Crevalle Jack - Habitat

Habitat

The crevalle jack lives in both inshore and offshore habitats, with larger adults preferring deeper waters than juveniles. In the inshore environment, crevalle jack inhabit shallow flats, sandy bays, beaches, seagrass beds, shallow reef complexes and lagoons, which may be open or landocked, and may be composites of the aforementioned environments. The species is also known to enter brackish waters, with some individuals known to penetrate far upstream; however, like most euryhaline species, they generally do not penetrate very far upriver. The water salinities where the species has been reported from range from 0% to 49%, indicating the species can adapt to a wide range of waters. Studies in West Africa found marked differences in the sex ratios of populations in brackish waters, with females very rarely seen in such environments once they are mature. Research in the coastal waters of Ghana suggests the availability of food is the primary control on the species distribution in inshore waters.

Adults that move offshore generally do not leave continental shelf waters, however still penetrate to depths of 350 m, and possibly deeper. These individuals live on the outer shelf edges, sill reefs and upper slopes of the deep reef, and tend to be more solitary than juveniles. Adults have also been sighted around the large oil rig platforms throughout the Gulf of Mexico, where they use the man-made structure like a reef to hunt prey. The larvae and young juveniles of the species live pelagically offshore along the continental shelf and slope, and are also known to congregate around oil platforms, as well as natural floating debris such as sargassum mats.