The Small Tortoiseshell is among the most well known butterflies in Britain and Ireland.
   Once one of the most common butterfly in Europe and  Asia, it is now in very rapid decline in Western Europe.
   The reason cannot be explained by the decline of its host plant, because the nettle is widespread and even enjoys the marked increase in the livability of it's environment.
   Small Tortoiseshells have one of the longest seasons of any Eurasian butterfly, extending from early spring to late autumn.
    Adults go through winter in hibernation, re-emerging on the first warm sunny days of the spring to mate and breed.
   In southern parts of their range there may be two broods each year, but northern Tortoiseshells are inhibited by the long length of summer days from breeding a second time.
   Male butterflies typically bask and feed until mid-day and then display territorial behavior until roosting.   
   Males typically defend a certain territory for up to 90 minutes, unless they attempt to follow a female or are ousted by another male.
   The next day they find a new territory to defend.           These territories tend to be sunny areas that females choose to lay their eggs.
   Very often, two or more males may share a territory if the cost of defending it is greater than the benefit gained from monopolizing the females.
    Small tortoiseshell are primarily red to orange in color, with black and yellow markings on the front wings and a ring of blue spots around the edge of the wings.
   (The Painted Lady is also orange with black spots, but without the yellow and blue markings.)
   The wings of Tortoiseshells conceal them very well from predators.
   When closed, the wings appear to be leaves, helping them to hide.
   When discovered, Tortoiseshells will flash their wings open to reveal bright colors.
   Since they lack the eyespots that many other butterflies display, these bright contrasting colors will often scare a predator, giving the Tortoiseshell time to escape. (Not only does this coloration tend to frighten birds, it can also act as a warning. The bright red coloration serves as a cautionary sign to the predator about the poor taste of the butterfly.) Tortoiseshells tend to be distasteful to birds because of the diet of their caterpillars.
   When bird notices this bright red coloring it will be less likely to eat the butterfly.
   
   *Aglais urticae is the national butterfly of Denmark.