Page 149 - Caribbean Reef Life Demo

(Caranx hippos) < 1 m / 3.5 ft
ar e lunt head. il er od ith ello ish ns and tail. i h lateral line. lac s ot on u er ill co er.
acks are fast silvery shes, large carnivores that can grow up to 35 kg in the case of the Crevalle ack above . As juveniles, jacks will often form tight schools, like the ellow acks on the left. These schools will often surround larger sh such as groupers. Rather than putting themselves in harm’s way, it is a form of protection; few predators on the reef will come close to a fully grown grouper. For the grouper, trying to catch the small and agile juveniles would be a waste of energy for very little food. This strategy gives the young jacks a bump up the food chain.
Bar acks often form hunting partnerships with other species of sh in a tactic called nuclear hunting. The sh have learned that by working together as a team they have a greater chance of a successful strike. Bar acks have also learned shadow hunting. They darken their bodies and swim near reef foragers, such as the og sh on the right, darting out to catch unwary prey.
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