Can Birds Get Drunk?
In 2018 the media ran numerous stories about residents of a small town in Minnesota filing reports to the police about the drunk and disorderly behaviour of the local bird population.
Several reports were received by the Gilbert Police Department of cedar waxwings supposedly under the influence flying into windows and cars, flopping about on the ground, and generally acting confused.
Some of the birds that collided with hard surfaces died and when autopsies were carried out on their bodies scientists discovered large amounts of fermented berries in their stomachs.
Cedar waxwings and their cousins Bohemian waxwings have evolved the largest livers of all bird species due to thousands of years of eating fermented fruit. This means that they have developed a level of tolerance to alcohol but although the residents of Gilbert had noticed slightly tipsy birds in previous years what happened during the winter of 2018 was on another level.
That year an early frost meant that berries favoured by the birds had fermented earlier than usual and before the waxwings had left for their southern wintering grounds. The cold temperatures concentrated the sugar in the fruit and as the weather warmed up the sugars quickly broke down producing alcohol with a similar strength to vodka.
Before migrating, birds fill up on as much food as they can in order to store up energy for the long journey ahead and the waxwings in Gilbert were no exception. As they gorged on the berries the amount of alcohol they were ingesting was too much even for their livers to handle and so they wound up drunk.
This was not the first time reports of drunk birds hit the media.
In November 2012 vets from the Animal Health and Veterinary Laboratories Agency (AHVLA) were called to a primary school in Cumbria to investigate the deaths of 14 young blackbirds and one who was clearly unwell.
At first the vets suspected foul play particularly as some of the birds were quite badly injured and the police were called.
Post mortem examinations and tests were conducted to rule out deadly infections such as avian flu but these came back negative. However, rowan berries were discovered in all of the birds’ guts which smelled as though they were fermenting.
Tissue samples from the dead birds were sent away for toxicology analysis which revealed high levels of ethanol in the birds’ bodies.
Staff at the wildlife centre where the surviving bird had been taken reported that it was acting as though it was drunk. It was unsteady on its feet and had to place its wings on the ground and lean against walls to keep itself from falling over. However, after a couple of days the bird made a full recovery and was released back into the wild.
Further investigation revealed that rowan berries that had fallen to the ground from trees nearby to where the blackbirds had been found were damaged which meant they would have been susceptible to a yeast infestation which would have precipitated fermentation and alcohol production. Although the vets could not be sure that the blackbirds had died from alcohol poisoning, they referred to a similar diagnosis made in 1999 in some redwings that had died after eating fermented holly berries. Samples of the berries taken from those birds’ crops and gizzards contained high levels of alcohol.
Drunk on the beach
Birds have also been known to get drunk on brewery waste. In 2018 the RSPCA had to rescue a number of gulls on the south coast that its officials said were “stinking of alcohol”.
The birds were found staggering around and struggling to stand but soon recovered after vomiting.
Most birds can recover from a drunken binge. Just like us they need some time to sleep it off. So if you come across an inebriated bird wrap it in a towel and put it in a box somewhere quiet and dark until it sobers up and starts behaving like a bird again.