When Humans Start Wars with Birds, It Never Ends Well

Clever cockatoos breaking into garbage cans for a bite to eat have been continually outsmarting the humans trying to stop them, sparking a new bird versus human war.

According to a paper published in the journal Current Biology on September 12, this inter-species interaction in Sydney, Australia, may be an example of an "innovation arms race".

Humans have an unexpectedly long history of going to war with birds.

bird wars
Stock image of a cockatoo (left) and an angry human (right). Residents of Sydney, Australia, are currently at war with their local cockatoo population over access to their garbage, joining the ranks of human-bird conflicts. iStock / Getty Images Plus

Also in Australia, back in 1932, residents declared war on the vast populations of emus living there, due to the amount of crop damage they were causing.

Several World War 1 veterans, armed with Lewis guns and 10,000 rounds of ammunition, attempted to wipe out a large group of the birds, but were unable to kill more than a few dozen of the emus. Due to negative media reaction to their lack of success, the soldiers withdrew, and the emus are widely considered to have been the victors of the "Emu War".

Another country that suffered an embarrassing defeat to avian foes was China, which attempted to eliminate rats, flies, mosquitoes and sparrows during the Four Pests campaign of the late 1950s. The sparrows were faced with their nests being destroyed, eggs broken, and chicks killed, as well as being shot down from the sky.

While these efforts nearly succeeded in driving the sparrows to extinction in the area, their absence unbalanced the ecosystem, leading to explosions in populations of their prey insects, including locusts, which destroyed crops anyway. This is thought to have contributed to the Great Chinese Famine, and China eventually imported 250,000 sparrows from the Soviet Union to replace them.

In the case of the Sydney neighborhoods, the consequences of the "war" isn't quite so extreme, with the main gripe of the humans being that the cockatoos spread garbage around the road. Their bins can't simply be sealed shut, as an automated arm on the garbage truck needs to be able to swing the bin open.

According to the paper, locals attempted to keep the birds out by other means, including putting bricks on top of their bin lids, blocking the hinges with sticks, and using ropes to prevent the lid from opening, but the cockatoos figured out a way around each time. This knowledge also appears to spread within the social structure of the birds, with others learning how to break into the bins by observing.

"We could actually show that this is a cultural trait," lead author Barbara Klump, a behavioral ecologist at the Max Planck Institute of Animal Behavior in Germany, said in a statement. "The cockatoos learn the behavior from observing other cockatoos and within each group they sort of have their own special technique, so across a wide geographic range the techniques are more dissimilar."

"It's not just a social learning on the cockatoo side, but it's also social learning on the human side," she says. "People come up with new protection methods on their own, but a lot of people actually learn it from their neighbors or people on their street, so they get their inspiration from someone else."

Further research of human-animal interactions will hopefully prevent future "wars" from breaking out, according to Klump.

"As cities expand, we will have more interactions with wildlife," Klump said. "I'm hoping that there will be a better understanding and more tolerance for the animals that we share our lives with."