The Pacific jack crevalle is found along the Pacific coast of the Baja California peninsula and in parts of northern Mexico. It is a schooling fish that can be found on sandy bottoms, near kelp beds, around jetties and breakwaters, and in estuaries.

The adult fish are typically found in shallow waters, from 4 to 7 feet (1.2 to 2 m) deep while juveniles are found at depths of up to 30 feet (9 m). Pacific jack crevalle prefer shallow waters but will move toward deeper water during the winter months or if there is not enough food available.

They are carnivorous predators and voraciously feed on small crustaceans, mollusks, and small fish, although they also follow schools of larger sardines or anchovies.

The Pacific jack crevalle reaches an average length of 20 inches (50 cm) with a maximum length of 3 1/2 feet (1 m). This species has many colors including silver, blue-green, olive green, brown, and black with a white belly. The tail fin is yellow with black spots on it while the anal fin is yellow with black spots on it as well. The caudal fin is forked and the dorsal fin is low set.

Jacks are an important fish to the commercial fishery in Baja due to the sheer number of them in the waters of both the Pacific and the Sea of Cortez. It's an equally important species to private anglers, earning its reputation as a fun powerfully fighting fish.