Red-collared lorikeets act as though they are drunk.
Some locals in the far north Australian city of Darwin say it is the drink that makes them fall over, bang into things and lose their inhibitions.
But veterinarians like The Ark Animal Hospital's Stephen Cutter question whether gorging on fermenting soft fruit is what makes red-collared lorikeets act as though they are drunk.
''It's definitely a seasonal thing because it's linked to what they are at at the start of the wet season,'' Cutter said. ''There's a low level (of drunken behavior) all year round but it reaches a peak from June to August.''
Darwin locals say there has always been the phenomenon of drunken parrots in the streets at this time of year. They have trouble flying. They lose coordination, and they lose their fear of humans.
All are agreed that each year more birds seem to display the behavior and they do so at about the same time.
But this might just be that people have become more caring, more likely to take a stricken bird to see a vet.
''The drunkenness is not exclusive to lorikeets, but it does affect one type of lorikeet, the red-collared lorikeet, more than any other,'' Cutter said. ''In these birds what we think is that it's a combination of alcohol poisoning from the fruit and a virus that makes them more susceptible to it.''
There is no treatment beyond making sure affected birds are safe and not dehydrated. But many do die from secondary infections.