Animals Wildlife Kleptoparasites: 8 Animals That Steal From Others By Melissa Breyer Melissa Breyer Twitter Editorial Director Hunter College F.I.T., State University of New York Cornell University Melissa Breyer is Treehugger’s editorial director. She is a sustainability expert and author whose work has been published by the New York Times and National Geographic, among others. Learn about our editorial process Updated November 5, 2020 Mark Bridger / Getty Images Share Twitter Pinterest Email Animals Wildlife Pets Animal Rights Endangered Species Kleptoparasites, animals that steal food or resources already procured by another animal, prove the ruthless nature of some in the animal kingdom. Kleptoparasites sometimes take resources from others of their species and sometimes outside their species. If you've ever had a brazen seagull snatch a sandwich from your picnic at the beach, you've played host to a kleptoparasite. Gulls aren't the only guileful ones — the following are some of the animals particularly adept at pulling a fast one when it comes to appropriating a meal. 1 of 8 Sperm Whales Gabriel Barathieu / Wikimedia Commons / CC BY 2.0 Sperm whales habitually steal fish from commercial fishers. In Alaska, sperm whales snag approximately 15 percent of sablefish off of longlines. SEASWAP researchers have observed that the sound of the hydraulics on fishing gear seems to let the whales know that an easy meal is available. Fishers also spot sperm whales sneaking fish from nets. Technology is being called into action with real-time tracking of whales so that fishing boats know to head elsewhere. 2 of 8 Western Gulls Luis Diaz Devesa / Getty Images Some seabirds, like the tern, dive into the depths to capture fish. Other seabirds, like the Western gull, are not diving birds. How is a non-diving bird supposed to catch fish? They take them straight from the beak of a diving bird or from the deck of fishing boats. 3 of 8 Dewdrop Spiders Jeevan Jose / Wikimedia Commons / CC BY-SA 4.0 Spiders from the Argyrodes genus, commonly known as dewdrop spiders, are some of the brassiest kleptoparasites around. Not only do they steal prey from other spiders' webs, but they invade and move into said webs as well. While the relationship can be beneficial to both spiders since the dewdrop will clean up smaller prey that would otherwise litter the web, things can turn grim quickly when the invading spider decides to devour the host as well. 4 of 8 Chinstrap Penguins Christopher Michel/ Flickr / CC by 2.0 While most commonly kleptoparasitism refers to animals that steal food, taking shelter materials from others earns the chinstrap penguin a spot on this list. They steal rocks from other penguin nests to improve the size and strength of their own. Male chinstrap penguins are the primary thieves. Their infamous behavior led to their mention in this glossary of biological terms under kleptoparasitism. 5 of 8 Water Crickets Mike Pennington / Geograph / CC BY-SA 2.0 The water cricket (Velia caprai) — a surface skating aquatic bug — has all kinds of sophisticated cricket tricks to perform. Along with developing such a terrible taste that trout actually spit them out unharmed, they are also known for their "expansion skating," whereby they spit onto the water to lower the surface tension, which allows them to double their travel speed. They are also great at practicing group kleptoparasitism. If one has some purloined prey that is too heavy to transport, other water crickets come to the rescue and help eat the prize. 6 of 8 Hyenas Anja Pietsch / Flickr / CC BY 2.0 Hyenas are no laughing matter. They are fascinating creatures, but they don't mess around; an adult spotted hyena can rip off and devour 30 or 40 pounds of flesh per feeding. Groups of hyenas surround lions with a kill and chase them off before stealing the food for their own. Don't feel bad for the lions, however; they often do the same to hyenas. 7 of 8 Cuckoo Bees Gilles Gonthier / Flickr / CC BY 2.0 Much in the way its namesake, the cuckoo bird, lays eggs in another bird's nest, the cuckoo bee also displays similar parasitism. But whereas the cuckoo bird chick is then raised by the other bird as its own, the cuckoo bee's plotline takes an even more sinister turn. Mama cuckoo bee lays her eggs in another bee’s nest, but the larvae hatch earlier than others, allowing it to feed on the provisions in store for the home bee's larvae. And then the cuckoo bee babies, with their extra-large mandibles, make mincemeat of the other larvae as well. 8 of 8 Humans Peter Muller / Getty Images Do you think we're above and beyond a bit of parasitism? The truth is, we're master kleptoparasites. There are many instances of people stealing food from other people, but we lift edibles from other species as well. Many people around the world rely on food killed by lions or other large carnivores, for example. And even closer to home, chances are you might be a kleptoparasite as well; have you eaten any honey lately?