Common Name: Jacks
Scientific Names: Caranx and Pseudocaranx species.
Description: Adults range from 50cm to 1m+. They are slim, sleek and powerful fish with forked tails, thin curved pectoral fins and often tall, prominent dorsal and anal fins. Colouration and the shape and extent of a line of large scales called scutes, near the tail can help tell the species apart. See also the Amberjack (30).
Distinctive Features: Jacks are fast, powerful predators with forked tails and often prominent pectoral, dorsal and anal fins.
Abundance: As individuals or small schools. At specific types of sites, namely off headlands and reefs sticking out into the current, they can be seen regularly. The key to success is to watch out for them in such places. They are often seen only for a moment as they speed by.
Habitat & Behaviour: These are predators of open water and the water column, feeding on the shoals of smaller fish which are attracted to the rich plankton that sweeps in with the water currents swirling around rocky reef headlands. They swim fast patrolling along, but then attack their prey fish with explosive darts into the shoals.
Reaction to Snorkellers & Divers:Mainly seen by divers in waters below 10 -15m.
Other Notes: There are about 4 species of ‘Jack’ that can be found in the Mediterranean. Even with photographs and careful observations they can be very difficult to identify underwater.
Text: Bob Earll
Photo: Russell & Gill Bennett
Video: Julia Jagoditsch