To Save Endangered Quolls, Conservationists Throw Toad Sausages Out of Helicopters

Michael J Barritt // CC-BY-SA 2.0
Michael J Barritt // CC-BY-SA 2.0 / Michael J Barritt // CC-BY-SA 2.0

There’s never been a good time to be a wild animal, but the past 150 years have been especially tough. Species are disappearing from our planet at an alarming rate, and many of those who remain are struggling to hang on.

Conservationists really have their work cut out for them. Many have started thinking way outside the box in order to succeed. Take, for example, the new plan to save endangered quolls by making it rain toad sausages.

The strategy may sound bizarre—and it is—but it’s rooted in good, solid science.

The northern quoll (Dasyurus hallucatus) is a kitten-sized marsupial that lives in Australia. It’s super-adorable, and super-endangered; in the last ten years, scientists estimate that the population has been cut in half. Predators and habitat loss have resulted in the northern quoll's eviction from most of its range. Just a few safe spaces remain, including the Kimberley region in Australia’s northwest corner.

“The Kimberley population is one of the last strongholds where quolls are doing well,” wildlife ecologist Jonathan Webb told Nature. “If we lose those quolls we’re looking at disaster.”

But the Kimberley may not be safe much longer. The region is under siege by the cane toad (Rhinella marina). Cane toads are not a native species; they were imported in the 1930s by the Australian government, who thought they might help control agricultural pests. That didn’t happen. Instead, the cane toads took over. This was relatively easy for them for three reasons: first, they breed like mad; second, they eat the young of other species and shove adults out of their nests; and third, they’re incredibly poisonous. Cane toads are all-around destroyers who even have a special strategy for eating each other.

Image Credit: benjamint444, Wikimedia Commons // GDFL 1.2

The cane toad’s poison is legendary, not just for its potency but for its hallucinogenic properties. But a little quoll that eats a cane toad won’t start seeing pink elephants; it’ll just drop dead. 

Because they’ve been so successful in taking over the territory, cane toads have started getting bigger, and with great size comes great poison. This is terrific for the toads, but really, really bad for the quolls, who can’t resist the sight of a fat, juicy toad.

At present, there’s simply no way to keep the quolls from eating cane toads. Any quoll that eats one won’t live long enough to learn its lesson, and it certainly won’t be able to warn its kin. The trick, then, is to teach the quolls that cane toads are not for eating.

How do you do that? Make them puke. Animals learn from experience, and will stay away from foods that have previously made them sick. Previous tests showed that getting sick once will convince quolls to keep cane toad off the menu.

Here’s where the sausages come in. Later this month, ecologists from the Australia Wildlife Conservancy will make special sausages from cane toad legs mixed with a vomit-inducing drug called thiabendazole. Then they’ll fly low over quoll territory, dropping sausages as they go. Camera traps on the ground will capture what happens next.

Getting the quolls to wise up won’t save them, but it may slow their decline. And hopefully, through experiences like this, we'll someday learn to stop meddling with our ecosystems. In the meantime, clever conservationists will do what they can.

[h/t: Justine E. Hausheer for Nature]