Sunday 23 June 2013

Painted Lady

The unseasonal weather of 2013 has been bad news for many of our butterflies and this has been born out by the results of our STERF Butterfly Atlas surveys.

However, there have been one or two individuals which seemed to be coping despite the unfavourable conditions.

One of these was a Painted Lady (Vanessa Cardui), flying today in winds gusting at around 28km per hour.

In a 1979 study by Gibo and Pallet, 30km per hour was determined as the wind speed cut-off point for Monarch Butterflies and in 2007, Jessica Grealey and David Stephenson, studying the effect of wind turbines on butterflies, concluded:
"Butterflies ...will not fly....when wind speeds are in excess of force five on the Beaufort wind scale -- 30 kilometers per hour (km/h) to 39 km/h [18.6-24.2 mph]."

So our Painted Lady was possibly flying at near the top end of acceptable wind speed.

Perhaps this is why it spent such a long time feeding on our Verbena bonariensis and was happy to pose for the camera!

1 comment:

Craig said...

Gorgeous - well captured guys! My Verbena Bonariensis isn't out yet but seeing yours reminds me of how much I'm looking forward to it.