102 Sharks: The Animal Answer Guideprevent infection (see “Do sharks socialize with other kinds of animals?”
in chapter 4). Torpedo rays show up in the stomach contents of Broad-
nose Sevengills and Sixgill (Hexanchus spp.) sharks. Some torpedos have
bite patterns on their backs indicating unsuccessful attacks by Sixgills, pos-
sibly because the torpedo was able to discharge its electricity before being
swallowed by the shark. Despite possessing toxic barbs, young stingrays fall
prey to other predators: Great Blue Herons have been observed spearing
and swallowing small Atlantic Stingrays in Florida and Mississippi.
The prominent fin spines of chimaeras and Spiny Dogfish may offer
some protection from predation. But chimaeras occasionally show up in
the stomach contents of other ratfish as well as some sharks and seals. Even
adult chimaeras are victimized, as shown by the presence of adult Austra-
lian Ghost Sharks in the stomachs of New Zealand Carpet Sharks (Cepha-
loscyllium isabellum) and School Sharks. White and Sevengill sharks happily
munch on Spiny Dogfish.
A number of mammals kill and eat sharks of all sizes. Smaller shark spe-
cies such as Horn Sharks are the prey of northern elephant seals (Mirounga
angustirostris), the seals feasting on adults, juveniles, and egg cases. Juvenile
Cape fur seals in South Africa have been seen capturing Puffadder Shy-
sharks and tossing them repeatedly in the air, slowly dismembering them.
The main object of this behavior doesn’t appear to be feeding so much as
playing with the shark, but the outcome is still usually fatal for the shark.
Even if the seal doesn’t eat the shark but drops it, Black-backed Kelp Gulls
are always around to finish the shark off. Adult Cape fur seals have been
filmed capturing and eating small Blue Sharks, also in South Africa.
Some of the biggest sharks fall victim to some of the ocean’s biggest
mammals. Sperm whales are best known for feeding on giant squid, butA Great Blue Heron captures a small
Atlantic Stingray in shallow water in
the Florida Keys. Moments later, the
heron swallowed the ray whole. Photo
by Kaye DeHays; used with permission
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