Birds
Hooded Pitohui
Pitohui dichrous · also called hooded pitohui
The hooded pitohui broke a long-standing assumption when researchers discovered, in the 1990s, that it is genuinely poisonous — its skin and feathers carry batrachotoxin, the same nerve poison as a poison dart frog. It gets the toxin from the beetles it eats, and its orange-and-black plumage warns predators away.
Overview
Hooded pitohuis live in forests across New Guinea, from lowland rainforest into hill forest. About 22–23 cm, boldly patterned with a black hood and orange-brown body, they eat fruit, seeds, and insects — including the toxic beetles that make them poisonous.
A poisonous bird
Its skin and feathers hold batrachotoxin, acquired from eating Choresine beetles, making it one of the very few birds known to be chemically defended.
A warning worn in feathers
The bold orange-and-black pattern acts as a warning signal, and several unrelated New Guinea birds have evolved to look similar.
Status
The hooded pitohui is Least Concern, widespread and common throughout New Guinea’s forests.
Hooded Pitohui: common questions
How can a bird be poisonous?
The hooded pitohui accumulates batrachotoxin, a powerful steroidal alkaloid that interferes with nerve and muscle function, in its skin and feathers, in the same way that certain poison dart frogs concentrate the same toxin in their skin. In both cases the animal does not synthesise the poison itself but obtains it from its diet, in the pitohui's case from eating small melyrid beetles of the genus Choresine, and then sequesters and stores the compound in its own tissues rather than breaking it down. Because the toxin is held in the outer body, on the skin and plumage, it works as a contact and taste deterrent against predators and parasites rather than being injected like venom.
How toxic is the hooded pitohui to humans?
Not dangerously so under normal circumstances, but the effect is noticeable and unpleasant. The researchers who first scientifically documented the bird's toxicity in the 1990s did so partly because handling the birds while removing them from nets, and touching their mouths afterward, produced persistent numbness, tingling, and a burning sensation in the skin and lips. Local hunters in New Guinea had long known the bird as a rubbish or bitter bird and generally avoided eating it, or prepared it specially, because its flesh and skin can cause similar unpleasant sensations. The amount of toxin on a single bird is far too small to seriously harm an adult human through casual contact.
Why is the hooded pitohui orange and black?
Its bold, high-contrast pattern of a black hood and wings against a bright orange-brown body is generally interpreted as aposematic, or warning, colouration, functioning to advertise the bird's chemical defence to predators so that a predator which has had one bad experience with a toxic pitohui learns to avoid birds with that appearance. Supporting this idea, several other, unrelated bird species that share the New Guinea forests, including some that are also toxic and some that may not be, have independently evolved strikingly similar orange-and-black plumage, a pattern of mutual resemblance among defended species that mirrors what is seen among toxic butterflies and frogs elsewhere in the world.
Are other birds poisonous like the hooded pitohui?
The hooded pitohui was the first bird conclusively shown to carry a defensive toxin, and research since then has identified the same or related batrachotoxins in several other New Guinea birds, including other pitohui species and the blue-capped ifrit, as well as trace toxicity in a few birds elsewhere. However, chemically defended birds remain rare and are concentrated in the forests of New Guinea, likely because that is where the toxic Choresine beetles they rely on are found. So while the hooded pitohui is no longer unique, poisonous birds are still very much the exception rather than the rule, in contrast to the many venomous and poisonous reptiles, amphibians, fish, and invertebrates.