Many years ago now, I lived in a house with a large garden. Next to the house was an old Madras Thorn (Pithecellobium dulce) tree which spread its branches to within a few feet of the walls. This tree flowered and produced fruit on a fairly regular basis but as far as I know this was not edible. At least I never tried to do so and perhaps this was wise. The fruit would on occasions fall to the ground during the day, after the gardener had swept up what had fallen overnight. It seems that some, if not all, of this was overripe and in some cases had even begun to ferment.
On many occasions I would come home from the office in the evening and find Javan Mynas (Acridotheres javanicus) on the verandah apparently dead to the world while others were staggering around tipsily having indulged a little too heavily in the overripe fruit. I took no notice of them nor they of me. By the morning they would all have disappeared, presumably with monumental hangovers.
Sadly for the mynas the tree had eventually to be cut down because the roots were causing trouble and furthermore it was infested with large millipedes which appeared to eat the layer under the bark, causing it to peel off and this eventually killed some of the big branches.
Contributed by Richard Hale
Image of ‘drunken’ myna courtesy of Saifuddin Suran
Additional comment by Nature Consultant, R Subaraj
Richard’s article is most interesting. We have long known that butterflies get rather tipsy drinking from fermented fruits and this can be viewed easily in captive collections at any butterfly farm. They are so stoned that you can place your finger under their legs and they will crawl onto them.
In many areas, particularly forested habitats, various birds and other animals feed on the fallen fruits lying on the ground below many a tree. Some of these fruits are obviously rotting and fermenting. One wonders whether these have a similar effect on other species. It would be great to receive feedback from anyone who has witnessed any similar disorientated behaviour.
Additionally, has anyone else seen anything feeding on the fruits of the Madras Thorn? This tree used to be a common sight around Singapore when I was growing up but nowadays, they are rather uncommon.
Many years ago in the western foothills of the California Sierra apple orchards were common and I happened to be next to one talking to a friend. At that moment, a Robin walked out from underneath his pickup eyed us and fell over on its’ side. “Don’t pay it no mind. It’ll be OK. it’s just drunk as a skunk. Look over there.”, he gestured toward the orchard. That’s when I noticed that it was full of noisy, very wobbly Robins. The apples still on the trees had frozen and fermented as they thawed.
Imagine, a bar room filled with drunks who could fly. They were singing, fighting, and missing branches by feet in their attempts to land. Occasionally, a bird would apparently just pass out and fall off a limb in the boneless drop of the truly whacked. Some had abandoned flight altogether and were weaving through the grass.
“It happens every so often when we get a frost before the pick’s finished. Robins are the worst. My wife says they must of was Irish in another life. Tommorrow, it’ll be real quiet. Man could make a fortune off asprin if those birds had money.”
Thanks anon. Yours is a very interesting account that locals in Singapore will find amusing. I will post it separately for their benefit. If you read this I would appreciate if you could get in touch with me so that I can acknowledge your contribution personally. YC
Pithecellobium dulce is a Mexican tree known as Guamúchil. The fruit (actually a pod) is eaten by humans and animals alike. Although many of these trees are present in my city (Torreon, Chihuahuan Desert, tree introduced not native) I have never observed this curious behaviour in our local birds (or humans, for that matter).
I am not sure but I think alcoholic fermentation is done by yeasts and some bacteria, and it’s an anaerobic process, unlikely to take place on the ground. Although I my be mistaken.
Lee Chiu San
Yes, animals do get drunk! I have read many accounts of elephants and bears becoming intoxicated during certain seasons of the year. And my first hand experience is that the parrot tribe are particularly bad offenders. My free-flying lories and lorikeets would help themselves to any unattended alcoholic drinks. And, unknown to us, our pet cockatoo drank a substantial quantity of Grand Marnier, then crawled under a table to sleep it off. Alarmed to find her pet groaning next morning, my wife rushed it off to the vet, Tan Hwa Luck. His advice was to simply let the bird sleep off the hangover.
HaHaHa. Most interesting.
Bird Ecology Study Group Feeding behaviour of butterflies
[…] The above video clip shows a Common Faun (Faunis canens arcesilas) feeding on a rotting fig. The slender proboscis can be seen dipping repeatedly into the exposed fruit as the butterfly sips the liquid. The juice from the rotting fruit provides sugars and their alcohol derivatives. This alcohol can render the butterflies drunk, causing them to remain still as they continue feeding, making them vulnerable to predators. Birds similarly become drunk after feeding on rotting fruits LINK. […]