Small Tortoiseshells

[Trev Sawyer]

There has been much talk over the past few years about the reduction in number of Small Tortoiseshells in Britain. I recently read that a species of parasitic fly (Sturmia bella) which targets the larvae if this butterfly had appeared over here during the last 5 years or so. This is obviously of concern, as I believe the disappearance of the Large Tortoiseshell from the UK was also largely down to a parasitic fly. Not sure what the current trend in numbers of the Small Tortoiseshell is (although I did see a few more last season than the one before), but we can only hope it is 'up'. Recent research showing that one Japanese butterfly at least (Ideopsis similis) has started to overcome the effects of being parasitised by this same Tachnid fly was published a few weeks ago and let's hope that if this fly continues to proliferate over here, that our good old Small Tort can fight back itself in a similar manner.
Maybe others with better butterfly knowledge than myself can confirm/deny the true cause of the recent variation in number of this butterfly, but I thought the above may be of interest.

Trev

[Dave McCormick]

I have seen loads in my area latley and I have 6 pupate so there should be a good number where I live by summer.

The number of small tortoiseshell is usually determined by the common wasp. The more there is the less small tortoiseshell. Over the past since I started seeing them, I have seen around 30+ small tortioseshell.

I am keeping a record and an eye on butterfly populations in my area and hoping to make sure all species stay. I am making sure this species stays. I will see what's going on with this fly and see what can be done.