Red-winged Parrots in Australia Exhibit Strange Behavior, Getting Drunk After Eating Too Many Fermented Mangoes.
Ripe mangoes, despite having very low ethanol content, can still intoxicate the parrots.
The end of the year marks the conclusion of the mango season in the Kimberley region of Australia, leading to many ripe mangoes falling to the ground. The red-winged parrots, a well-known bird species in the area, love to eat mangoes and take advantage of the last fruits available.
They forage for the mangoes that have fallen to the ground. However, as ripe mangoes contain a lot of sugar, exposure to sunlight causes them to ferment. Even with very low ethanol content, it can still lead to the parrots becoming intoxicated.
Michael Considine, an associate professor of biological sciences at the University of Western Australia, stated: “When the fruit ripens, the next stage is fermentation, where sugars convert into alcohol, and this process produces volatile aromatic compounds that attract birds and other animals.”
The last ripe mangoes of the season fall to the ground.
Veterinarian Paul Murphy treated at least six parrots showing symptoms of ethanol poisoning at the Broome Veterinary Hospital in Broome. He said: “Typically, they suffer for a few days… They are quite lethargic and are at various stages of malnutrition.”
These cases were fortunate to be rescued, as many other parrots have died or crashed into obstacles, collided with cars, or were too intoxicated to escape predators.
“We have heard reports of them flying into windows and then sitting on the floor, unable to fly, making them vulnerable to cats and other predators,” Paul Murphy remarked.
According to Michael Considine, ripe mangoes are the cause of the drunken behavior of red-winged parrots, which is the only bird species significantly affected by fermented mangoes. Some scientists believe that mangoes may be the only wild fruit throughout Kimberley that ferments strongly.
A few years ago, groups of parrots became addicted to opium, raiding poppy fields in India despite numerous prevention measures. In 2018, drunken birds caused a stir in a city in Minnesota, USA.
The police in Gilbert, Minnesota received reports of birds behaving erratically, such as flying into windows and moving cars, exhibiting various confusing behaviors. They became intoxicated after consuming too much fermented fruit.
