Hot on the heels of revelations about murderous tortoises comes a new study about equally deadly centipedes that hunt and eat birds.
Predominantly carnivorous, centipedes – which are predatory arthropods, belonging to the same animal group as millipedes and other multi-legged monsters – are one of the largest invertebrate predators on land.
The residents of Phillip Island, which neighbours Norfolk Island in the South Pacific, 1400 kilometres due east of Byron Bay, know this all too well.
Monash University researchers recently discovered that the massive Phillip Island centipede (Cormocephalus coynei) can kill and consume up to 3700 seabird chicks every year.
Their study, published in the journal The American Naturalist, monitored the diet of these nocturnal critters for 132 hours. Up to 30 centimetres long, with pincer-like appendages that allow them to inject venom into their victims, the centipedes stalk their prey through the thick leaf litter of the forest floor.
“The centipede hunts an unexpectedly varied range of quarry, from crickets to seabird chicks, geckos and skinks,” the researchers write in a piece published in The Conversation. “It even hunts fish – dropped by seabirds called black noddies (Anous minuta) that make their nests in the trees above.”
The researchers found that 48% of the centipedes’ diet consisted of vertebrate animals – and 8% of that came from seabird chicks.
By monitoring both centipede feeding activities and black-winged petrel chicks in their burrow nests on the forest floor, the researchers realised that the centipedes were targeting the chicks – and they even saw one go in for the kill.
Monash researcher Luke Halpin explains that the chicks are vulnerable because they are left alone for long stretches of time: “The parents leave them and make big journeys out to sea in search of food, often many thousands of kilometres before they return to the chick to feed it.”
Halpin and team estimate the centipedes kill between 2109 and 3724 petrel chicks every year.
“Petrels produce a single offspring per year; therefore, predation of nestlings by centipedes represents total breeding failure for a pair in a given year,” they write in the paper.
But the researchers stress this is entirely natural behaviour.
“By preying on vertebrates, the centipedes trap nutrients brought from the ocean by seabirds and distribute them around the island,” they write.
“In some sense, they’ve taken the place (or ecological niche) of predatory mammals, which are absent from the island.”