www.ukbutterflies.co.uk

I've been sent a video of some mud-puddling Green-veined Whites. Every so often, they rapidly and collectively vibrate their wings in synchronisation. Is this typical of mud-puddling behaviour and does it have an explanation?
regards
Rob

It would be interesting to know what the stimulus was - whether it was external to the group or generated by (one of) the whites themselves.

I remember photographing a zephyr blue on damp ground. My dog was some distance away and began barking at something - another dog, I expect. In exact synchrony with her barks, the blue flashed open its wings. I wish I'd filmed it, but by the time I'd registered what was happening and thought, 'that's interesting', she stopped barking.

Is there anything audible in the video?

Guy

I have some film of Green-veined Whites at Chambers Farm, Lincs - mud puddling.

I thought this was unusual for the UK, and did note that they vibrate their wings for some reason - possibly cooling or deterring predators?

There is no audible stimulus, the background is quiet, it looks as if one butterfly starts first and the others join in.

The footage of mud-puddling Green-veined Whites below was also taken in Lincolnshire. I suspect from this footage that the stimulus is, as Guy suggests, generated by one of the whites themselves. In this case, it seems that much of the synchronisation often corresponds with movement of another GVW into a new position close to those who then vibrate. Other sound waves / vibrations from nearby dogs may perhaps impact in a similar manner. The reason? Very much open to debate, but possibly as Jason suggests as a defense mechanism to deter predators, or maybe as a territorial response for other males to keep back?


https://www.youtube.com/watch?v=ii3hf4E_AYE

Thanks very much for all your replies. Looking at the clip again, it is painfully obvious that the synchronised movement is set off by an incoming male, who then adopts similar behaviour once settled. As you say, it could be a normal defensive or territorial mechanism by each individual that has the effect of group synchronisation.
best wishes, Rob