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Chapter 7
Foods and Feeding
What do sharks eat?
The most general statement that can be made about feeding patterns
in sharks is that they are opportunists, eating just about anything. Except
plants: sharks don’t like brussels sprouts, perhaps attesting to their intel-
ligence. Actually, chondrichthyan fishes don’t like any vegetables or fruits.
They are as a group entirely carnivorous, eating all types of marine animal
life that they can catch, or scavenging on dead animals that other sharks
have dismembered. Bony fishes make up 70% to 80% of the diet of most
shark species, although a variety of species also eat lobsters and crabs, squid
and octopus, porpoises and whales, seabirds, sea turtles, and other sharks.
Opportunism means eating what’s available. Galapagos Sharks in the Gala-
pagos Islands feed on marine iguanas, a prey type not available anywhere
else in the world. But marine iguanas are large, tasty, and slow-swimming.
An example of a shark with a diverse diet, highlighting a species about
which we know comparably little, is the Broadnose Sevengill Shark. Among
food items found in the stomachs of Sevengills in South Africa have been
at least 11 species of sharks; 2 each of skate, stingray, and torpedo ray spe-
cies; shark egg cases; a chimaera; a hagfish; more than 14 kinds of bony
fishes; and squid, octopus, snails, crustaceans, seals, and dolphins. In other
places, Sevengills also eat sea lions, rats, and people. The human remains
were scavenged from a suicide victim who had jumped off the Golden Gate
Bridge.
Scavenging is an important feeding mode in many sharks. Their scav-
enging habit, coupled with an exquisite sense of smell that allows them to
detect baited hooks from great distances, is part of what makes sharks so