Animals don’t particularly care if they smell bad—and if that stink happens to keep away hungry predators or curious humans, so much the better. On the following slides, you’ll discover the 11 smelliest species in the animal kingdom, ranging from the appropriately named stinkbird to the ocean-dwelling sea hare.
Also known as the hoatzin, the stinkbird has one of the most unusual digestive systems in the avian kingdom: the food this bird eats is digested by bacteria in its fore gut rather than its hind gut, which makes it broadly similar in anatomy to ruminant mammals like cows. The rotting food in its two-chambered crop emits a manure-like odor, which makes the stinkbird food of last resort among the indigenous human settlers of South America. You might imagine a bird this stinky would subsist on slimy frogs and poisonous snakes, but in fact the hoatzin is a confirmed vegetarian, feeding exclusively on leaves, flowers and fruits.
The Southern Tamandua
Also known as the lesser anteater–to distinguish it from its better-known cousin, the greater anteater—the southern tamandua is every bit as stinky as a skunk, and (depending on your inclinations) a lot less pleasant to look at, too. Normally, an animal the size of a tamandua would make a quick meal for a hungry jaguar, but when attacked, this South American mammal releases a horrible odour from its anal gland at the base of its tail. As if that weren’t repellent enough, the southern tamandua is also equipped with a prehensile tail, and its muscular arms, capped with long claws, can bat a hungry margay clear over to the next tree.
The Bombardier Beetle
One can imagine a bombardier beetle rubbing its forelimbs together and delivering the villain’s monologue in an action film: “Do you see these two flasks I’m holding? One of them contains a chemical called hydroquinone. The other is filled with hydrogen peroxide, the same stuff you used to dye your pretty blonde hair. If I mix these flasks together, they will quickly attain the boiling point of water and you will dissolve in a pile of sticky, stinky goo.” Fortunately, the bombardier beetle’s chemical arsenal is only fatal to other insects, not humans. (And curiously, the evolution of this beetle’s defence mechanism has been a subject of enduring interest to believers in “intelligent design.”)
Here’s the part they left out of all those Hugh Jackman film: real-life wolverines are some of the world’s smelliest animals, to the extent that they’re occasionally called “skunk bears” or “nasty cats.” Wolverines are not at all related to wolves, but are technically mustelids, which puts them in the same family as weasels, badgers, ferrets, and other stinky, slinky mammals. Unlike the case with some other animals on this list, the wolverine doesn’t deploy its acrid scent to defend itself from other mammals; rather, it uses the strong secretions from its anal gland to mark its territory and signal sexual availability during mating season.
The King Ratsnake
One doesn’t normally associate snakes with bad smells–poisonous bites, yes, and chokeholds that slowly squeeze the life out of their victims, but not bad smells. Well, the king ratsnake of Asia is the exception: also known as the “stink snake” or the “stinking goddess,” it’s equipped with post-anal glands that it quickly empties when threatened, with the expected results. You might think such a feature would evolve in a tiny, otherwise defenseless snake, but in fact, the king ratsnake can attain lengths of up to eight feet—and its favorite prey consists of other snakes, including the almost-as-unpleasant Chinese cobra.
A widespread bird of Africa and Eurasia, the hoopoe isn’t stinky 24-7, but only enough to make you never want to see one ever again for the rest of your life. When a female hoopoe is breeding or incubating her eggs, her “preen gland” is chemically modified to produce a liquid that smells like rotting meat, which she promptly spreads all over her feathers. Newly hatched hoopoes of both sexes are also equipped with these modified glands, and to make matters worse, they have a habit of defecating explosively (and stinkily) all over unwanted visitors. It remains an enduring mystery why hoopoes are almost never sold in pet shops!
The Tasmanian Devil
If you’re of a certain age, you may remember the Tasmanian devil as the whirling, slobbering nemesis of Bugs Bunny. In fact, this is a meat-eating marsupial native to the Australian island of Tasmania, and while it doesn’t like to spin around, it does like to stink things up: when it’s stressed out, a Tasmanian devil releases a smell so strong that a predator will think twice about turning it into a meal. Usually, though, most people never get close enough to a Tasmanian devil to activate its stink instinct; they’re usually repelled well in advance by this marsupial’s loud, unpleasant screech and its habit of loudly and sloppily eating its freshly killed food.
The Striped Polecat
Yet another member of the mustelid family (like the skunk and the wolverine, seen elsewhere on this list), the striped polecat is known far and wide for its unpleasant smell. (Here’s an interesting historical fact: when the cowboys of the Old West referenced dirty-dealing “polecats,” they were actually talking about striped skunks, not this African mammal of which they would have been completely unaware.) The striped polecat uses its odoriferous anal gland to mark its territory, and also directs blinding chemical sprays to predators’ eyes after first adopting the classic “threat stance” (back arched, tail straight up in the air, and rear end facing you-know-who).
The Musk Ox
Being in a herd of rutting musk oxen is kind of like being in the locker room of an NFL team after an overtime game—you will notice a, how shall we put it, piquant odor that (depending on your proclivities) you will find either enticing or nauseating. During mating season, in early summer, the male musk ox secretes a smelly liquid from special glands near its eyes, which it then proceeds to rub into its fur. This unique stink attracts receptive females, who wait patiently nearby while the males battle one another for dominance, lowering their heads and slamming into each other at high speeds. (Not to judge other animals by human standards, but dominant male musk oxen have been known to keep females captive within the herd, and also to kick them, hard, when they’re not cooperative.)
The skunk is the most well-known smelly animal in the world–so why is it so far down on this list? Well, unless you’ve been living in an isolation chamber since birth, you already know that it’s never a good idea to go near a skunk, which won’t hesitate to spray predatory animals (and inquisitive humans) whenever it’s feeling threatened. Contrary to popular belief, you can’t really get rid of that deep-drenched skunk smell by bathing in tomato juice; instead, the Humane Society of the United States recommends a mixture of hydrogen peroxide, baking soda, and dishwashing soap. (By the way, there are about a dozen skunk species, ranging from the familiar striped skunk to the slightly more exotic Palawan stink badger.)
The Sea Hare
“Smell” carries a very different connotation under the water than it does on land or in the air. Still, there’s no doubt that fish, sharks, and crustaceans react negatively to toxic squirts, and no marine invertebrate squirts more toxically than the sea hare, a species of soft-shelled mollusk. When threatened, the sea hare emits a cloud of crazy purple knockout gas, which quickly overwhelms and then short-circuits a predator’s olfactory nerves. As if that weren’t enough, this mollusk is also poisonous to eat, and is covered with a clear, unappetizing, mildly irritating slime. (Believe it or not, but the sea hare is a popular gourmet item in China, where it’s usually served deep-fried in pungent sauce.)