www.ukbutterflies.co.uk

I am fascinated by the recent expansion of the range of some butterflies into East Lothian. The Comma made only the odd appearance into East Lothian prior to 2006, but is now well established and quite commonly seen. Wall Browns made it here three years ago after gradually extending northwards up the Berwickshire coast. Speckled Woods and Small Skippers arrived last year and it looks as though Holly Blues are hiding somewhere around North Berwick. Considering that any suitable habitat is being lost at an alarming rate here and given the weather we have had over the last few summers I would have expected a loss of species rather than increase.
We don't have anything like the number of species found further south, though.
Anyway, does anyone know where I can find out about historic distributions of butterlies? I have been told that 30 or 40 years ago there were no Orange Tips or Peacocks here. I would love to find out more.

There is some information on the web but I've never seen any publication in which all species are included:

http://www.butterfly-conservation.org/uploads/sobb.pdf

The handout made available at last year's BC AGM is now online and one of the speakers highlighted how south east Scotland was probably the most exciting place right now regarding new species:

http://www.butterfly-conservation.org/u ... 202011.pdf

Hi Nick,

In 1970 the Biological Records Centre as part of the European Invertebrate Survey published the Provisional Atlas of the Insects of the British Isles (Part 1 Lepidoptera Rhopalocera). This contained detailed distribution maps based on data received from recorders up to 31 December 1969 (sample below). I have the maps in digital format if there are any particular species you are interested in. More recently, The Millennium Atlas of Butterflies in Britain and Ireland was published in 2001. A update, in the form of The State of Butterflies in Britain and Ireland was published in 2006. If you want to go deeper, The British Butterflies - Their Origin and Establishment by R L H Dennis was published in 1977 and is a detailed and fascinating work on the origin and subsequent establishment of the British Lepidoptera.

I hope this helps?

Good hunting.

Kind regards. Mark

Mark, if you 'google' that Atlas you get the following web address returned:

http://nora.nerc.ac.uk/8104/1/Insect_at ... mplete.pdf

Is this the complete set?

Hi David,

Thanks for the link.

Yes, this is the complete set and the same document as my own, although a scanning error has duplicated item 11, the Large White.

Kind regards. Mark

Wow, thank you gentlemen. What a lot of interesting information. That will keep me occupied for some time!!

Hi Nick
It is also worth checking old copies of entomological books as these often have old distribution maps in. I do not have it to hand but In have a 1980's copy of 'British Butterflies' by Ford which is I think a reprint of an earlier book. It contains distribution maps from the early twentieth century which make interesting reading. I noticed that the Chequered Skipper was shown to include Northern England in its distribution earlier in the century if I remember correctly.
It is worth noting that the earlier records are likely to be less accurate and less complete than modern records.

jackz432r wrote:Hi Nick
It is also worth checking old copies of entomological books as these often have old distribution maps in. I do not have it to hand but In have a 1980's copy of 'British Butterflies' by Ford which is I think a reprint of an earlier book. It contains distribution maps from the early twentieth century which make interesting reading. I noticed that the Chequered Skipper was shown to include Northern England in its distribution earlier in the century if I remember correctly.
It is worth noting that the earlier records are likely to be less accurate and less complete than modern records.

Ah, good idea. I have Collins Field Guide to Butterflies from 1973, which has distribution maps in it. From a quick scan I notice that they are a little different from the maps in the 1969 document. Certainly the 1969 document above shows that we didn't then have Orange Tips, Peacocks, Commas, Ringlets, Wall Browns, Speckled Woods, Holly Blues or Small Skippers. That's a third of the current list! What a dull place it would have been then!

I think you have to treat earlier distribution records with some scepticism, since there were far fewer individuals out monitoring butterfly populations, meaning the number of squares actually recorded as containing certain species were regularly not marked simply because no-one was reporting their presence.

For instance, to look at the 1969 records for Brown Hairstreak, you would be tempted to believe that the species was entirely absent from Wales. However, there are colonies in many parts of the south west of the principality that could not suddenly have migrated there in the last 40 years without also colonising the area in between here and their next nearest populations to the east, i.e. in this case, Gloucestershire.

To some extent, this is still happening today. Species with a presence in areas of low human population are often much under-recorded, which means that Northern Brown Argus, Large Heath, Mountain Ringlet, Chequered Skipper et al may yet prove to be more widespread than we currently realise.