South Downs Blues Festival

We want your Brimstones

As part of our ongoing atlas survey we are very keen to establish current distribution patterns for the downland blue butterflies; small blue, chalkhill blue and adonis blue. Sussex Butterfly Conservation is working closely with the South Downs National Park to improve habitats all across the South Downs for these species. Accurate distributions maps are vital to help us monitor the future success of this work.

There are a number of 'gaps' in our atlas data so far. Sussex Butterfly Conservation members have been targetting these gaps and, in many cases, we are finding that the Downland in these 2km tetrads is not suitable to support these butterflies. However the squares listed below have potential. Please help us by visiting these squares, recording ALL butterfly species present and reporting back to the sightings page of the website or emailing Michael at

The 2km tetrads are listed below. To view these squares please visit Grab –A-Grid Reference website ( enter the grid reference into the 'go to' box, tick grid reference and the 2km square option and the tetrad square is outlined in pink. If you would like maps and further details please contact Michael at

ALSO: Please check all these squares for Silver-spotted Skipper too!

Here's a few squares to get us started, all around Brighton – I'll be adding a load more over the next few days just in time for the nice weather coming up in the week.


Adonis Blue

Adonis Blue

Found in clonies across the South Downs from Beachy Head to Amberley – but that's where it stops. We have no records west of TQ0410. Can you find any deep in West Sussex – or help us fill in some gaps elsewhere.

Identification details at:


Small Blue

Small Blue

Thinly distributed in small colonies from Cocking to Beachy Head. This butterfly is found in sheltered areas – so keep out of the wind and look out for our smallest British butterfly.

Identification details at:


Chalkhill Blue

Chalkhill Blue

Found in large colonies across the Downs whereever there is suitable chalk downland habitat. Some of the colonies can contain over a million butterflies. There is a huge gap in our records between Amberley and Goodwood. Despite searching we just can't find the butterfly – or any suitable habitat for it – in this area. Can you? Otherwise plenty of gaps to be filled. In 2012 and 2013 this butterfly has also mysteriously started appearing all over the Sussex – are they wandering or have they adapted to different habitats?

Identification details at:



Around Brighton

TQ2408 Cookroost Hill: North of Mile Oak

Access through a number of footpaths crossing the square. No Small, Chalkhill or Adonis records yet from this square. No Silver-spotted Skipper.


TQ2608 Skeleton Hovel: North of Hangleton / South of Devil's Dyke

There's a few golf courses in this square which is easily accessed by footpaths and the road to the Devil's Dyke. No Chalkhill or Adonis yet – but there are Small Blues here. No Silver-spotted Skipper.


TQ2808 Waterhall: North of Pathcham

None of the blues at this site although the area at Waterhall is managed for wildlife and grazed (see details at Also home of the Brighton Blues rugby team. No Silver-spotted Skipper.


TQ2810 Pangdean Farm: South of Pyecombe

The A23 cuts right through this square but there is footpath access on the west side of the square where there is the best potential for these species. No blues in this square. No Silver-spotted Skipper.


TQ4600 Bishopstone: Near Seaford

Hmmm... I thought we had this square covered. Even though we have Silver-spotted Skipper and Small Blue in this square we don't have Chalkhill or Adonis. The downland to the north-west of the village should help to rectify this.


TQ3802 Pedlersburgh: Above Saltdean / Telscombe Cliffs

Another square where we have recorded Silver-spotted Skipper but none of the blues. The square is criss-crossed with footpaths and the area in the NE corner looks promising.


TQ3410 Stanmer Down: North of Sussex University


There are a few squares in this area which are blank for the blues. Surveying here has shown that the habitat is not available in the square. However this tetrad looks like it has potential.


TQ0610 Wepham Down: West of Storrington

This square is just below Kithurst Hill – one of the richest 2km sq in Sussex for butterflies. Surely there must be some of the blues here? Also keep an eye to the ground for Silver-spotted Skipper. This area is the western edge of its current known range in Sussex.


TQ0412 Rackham Hill: Near Amberley

This north-facing slope may not be ideal for the blues – but we have plenty of records here for other downland species including Small Blue - so it's worth checking again on a hot day. This area is close to Silver-spotted skipper territory too. The square to the south is our most westerly Adonis colony.


TV5698 Pea Down: West of Eastbourne

As long as it doesn't Pea Down and you have a hot, calm day then this square has potential. It's surrounded by squares which hold all of our target species but this land is mostly agricultural. However there does appear to be some valley bottoms which will more than likely hold a blue or two.


SU8412 West Dean

We're too far west for Silver-spotted Skipper and Adnois Blue here but this square is a noticeable gap in our Chalkhill records.