Population crash of N.antiopa in DK

[Niklas Wahlberg]

Hi all,
   I wonder what has hit the nymphalines in Fenno-Scandia? In Finland we
have had a crash of the small tortoiseshell (Aglais urticae). Nymphalis
antiopa has not experienced the same however. A. urticae has been one of
the most common butterflies for the past few years (probably longer), but
this year I have not seen any and friends of mine have seen only one or two.

Cheers,
Niklas Wahlberg