Cuttlefish Diet

Cuttlefish are cephalopods, relatives of squid and octopi. These dynamic invertebrates, broadly distributed in coastal waters as a family, can shift color depending on mood and intent, spew ink to confuse would-be predators and---overall---possess formidable brains. As in many organisms, some of their most striking behavior emerges in the pursuit of food.

  1. Prey Preference

    • The diet of cuttlefish evolves with age and size. Researchers have noticed that the primary prey of cuttlefish off the coast of northwestern Spain, for example, shift from crustaceans to fish and mollusks as the cephalopod matures. Common cuttlefish hatchlings feast on shrimp, while juveniles favor crustaceans---swallowing smaller ones entire, and cutting larger victims into pieces.

    Predatory Technique

    • Prey of different size and type may inspire varying predatory strategies. Common cuttlefish dispatch prawns with lightning nabs of their tentacular clubs; this pair of long arms pulls the shrimp into the crushing beak. Researchers have classified the cuttlefish attack process into three stages: attention, positioning---the cuttlefish fixating on its intended victim and then orienting itself for prime striking distance---and seizure. While smaller crabs may be procured with the long tentacles in the same manner as shrimp, those larger than the cuttlefish itself are more likely to be seized with arms and body. To avoid the crabs' pinching claws, experienced cuttlefish typically strike the crustaceans from the rear, a technique that may be learned through trial and error. Cuttlefish saliva contains cephalotoxin, a paralyzing agent; this helps subdue their prey.

    Giant of the Family

    • One of the largest species, the Australian giant cuttlefish, which may weigh over 10 lbs., consumes primarily prawns, crabs and small fish.

    Cuttlefish as Pets

    • Cuttlefish are quite popular in home aquariums, but their hearty appetite should be considered by any would-be caretaker. According to Colin Dunlop in the Octopus News Magazine Online, babies can snack on five half-inch shrimp and half-grown specimens will down two crabs on a daily basis---again, prey size preference reflects cuttlefish growth. Cuttlefishes' voraciousness---and their ability to tackle animals larger than themselves---make the selection of other creatures to share their tanks a delicate operation; fish and most crabs are not appropriate, while starfish, for example, may be.