Plum drunk: the red admirals all on board for a last boozy feast

For well over a week now the air under the plum tree has reeked like the dregs of a half-drunk bottle of red wine left opened for a fortnight – alcoholic and vinegary. I can not remember such a good plum crop, ever. After the pies and the jam and the ones that were frozen or given away, the fallen plums could only be left to rot, but I piled some on the bird table in the sun. Soon the red admirals arrived.

Sometimes there were as many as seven butterflies on just one of the wire mesh trays, drinking the juice that oozed from the plum flesh; eight if you counted the one underneath, drinking the liquid that seeped through from above.

By late afternoon the butterflies had all become stupefied. When I touched them, most merely responded with an irritated flick of their wings. Others flew in a circle, then returned. Two settled on me, on my arm and in my hair. They had completely lost their inhibitions.

In the warmth of an Indian summer the yeast that formed the bloom on the plum skin had fermented the sugar to alcohol. The anthropomorphic conclusion was inescapable; these butterflies were in a drunken stupor.

Further proof came from the hybrid buddleia whose orange flowers arched overhead. The plant, a Buddleia x weyeriana, produces abundant nectar until the first frosts and it was crawling with bumblebees, though bereft of butterflies. For red admirals fermented plum juice seemed to be a far greater attraction than simple nectar; though I never saw bumblebees, models of sobriety, tempted by the plum juice.

Watching, it became clear there was a feeding hierarchy for butterfly species, with flare-ups of aggression. The red admirals tolerated each other as long as their wings or antennae did not touch, but they flicked their wings violently when a peacock landed. Two speckled woods that tried to join in were seen off in a matter of seconds.

Late this afternoon they were still there, some now with tattered wings, living their final days in their last chance saloon before cold nights, bad weather and the last of the plums brought their boozy feast to an end.

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