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Mediterranean invasive species factsheet

Similar species chromis or Sardinella aurita may occur. In addition,
The shrimp scad can be confused with several other many researchers consider that the lower predation
species of the Carangidae family. Several Caranx pressure on A. djedaba in shallow waters can lead to
species and Pseudocaranx dentex have a similar a greater abundance of juvenile shrimp scads in
ellipsoidal, compressed body shape and a line of these habitats.
scutes along the lateral line. However, the posterior
part of their pectoral fins, when folded along the Economic impacts
flanks, does not overlap the first scutes. In the Mediterranean its large schools are caught by
Alepes djedaba can also be distinguished from beach seine, purse seine and trammel nets, as this
native Mediterranean species by the presence of an fish has some commercial value.
adipose membrane covering the posterior half of the
eyes, and a black spot on the edge of the gill cover. Management options
These include a) early eradication of new
Lateral line slightly curved
populations by MPA operators through fishing, and b)
maintenance of healthy and abundant assemblages
of top predators to encourage natural control
through predation.

Further reading
Carpenter, K.E., et al. 1997. FAO Species Identification
Field Guide for Fishery Purposes. Living marine resources
Black spots Tail fin with of Kuwait, eastern Saudi Arabia, Bahrain, Qatar, and the
dark edges United Arab Emirates.
Caranx crysos http://www.ciesm.org/atlas/Alepesdjedaba.php

Caranx rhonchus. Photo: A.M. Arias

Brief history of its introduction and
pathways
The shrimp scad is widely distributed in the Indo-
Pacific. The first individual in the Mediterranean Sea
was recorded along the Palestinian coast in 1927
(as Caranx calla). It has subsequently been
recorded in the Aegean Sea, Egypt and Greece and
is now a very common species in the Levant.

Alepes djedaba. Photo: P. Consoli
Ecological impacts
The shrimp scad can form large schools around Drawings: Juan Varela
natural or artificial reefs. Competition with some
native zooplanktivorous species such as Chromis

96 Monitoring Marine Invasive Species in Mediterranean MPAs: A strategy and practical guide for managers