Latest Dorset Butterfly Atlas now out!

Map showing all places butterflies recorded in 2015-19

Take nearly a million butterfly records and some amazing work by our Dorset number crunchers and what do you get? We are proud to announce the answer is: the latest Dorset Butterfly Atlas!

This new atlas looks at where each butterfly species has been seen in Dorset over the years 2015-19.

  • We have also added information on how the distribution of each species in this time period compares with that of 2000-2004, and looked at some longer term distribution trends, comparing the results for 1990-2004 with 2005-2019. It is important to use both comparisons as they reveal different issues about the species.
  • All our earlier published Atlases are now on the website So if you wish you can go back and see how things have changed over the years. There is some deliberate overlap of data with present Atlas.
  • Butterflies are recorded all over the UK on a five-year cycle.
  • Records are brought together from the website, transect (butterfly monitoring) walks and many other sources to produce these results. Every butterfly seen and recorded in Dorset over the last 5 years is in the dataset!
  • Any site only has to be visited once over the five-year period to be counted, so there is a good chance that important colonies will be recorded.
  • In this latest recording period we achieved an astonishing 90% coverage of the kilometre squares in Dorset: the best yet for a five-year period!
  • When you look at the data it mentions “distribution”. This refers to the coverage of each species within each kilometre square in Dorset.
  • The other measure we can use is abundance – how many of each species are seen. We do compare numbers of butterflies counted on our transect walks and publish highlights in our annual Butterfly Report.
  • The Atlas will help inform our efforts to conserve Dorset butterflies by telling us where they are and whether they are doing well or badly.

The maps below give an idea of how varied the distribution of various species is in the County:

Two maps of Dorset with few and many squares filled respectively

Well done to everyone who helped collect these records: your help in this work is greatly appreciated!

The map is now wiped clean and we have to try and do even better in 2020-2024, so keep on sending in your sightings.

2 thoughts on “Latest Dorset Butterfly Atlas now out!

  1. lynpullen

    Hi Mark. We are only offering this in (free) online format – there is now a link to the appropriate page, which may have been missing when you read the post, for which my apologies. Lyn.


Leave a Reply