Blues and Arguses in Sussex

 Globally, chalk landscapes are rare but growing up in the outskirts of Brighton in East Sussex, I was very familiar with the South Downs around Brighton and Lewes. They were a regular playground for me during the school holidays and in the 1960's they were awash with blue butterflies.

I fondly remember those halcyon days, which seemed forever bathed in warm sunshine and where my passion for butterflies was seeded.

The blues and arguses are part of the Lycaenidae family and chalk downland is the best habitat in which to go looking for them. That said, only three species are predominantly restricted to a downland habitat. Another three species are much more catholic in their habitat requirements, one is a migrant and one is only to be found on heathland.

Common Blue (Polyommatus icarus)

This species can be found in any suitable habitat in Sussex, from chalk downland to woodland glades, roadside verges and suburban gardens.

(male)

(female)

(mating)

Chalkhill Blue (Polyommatus coridon)

As its name suggests, this species is predominantly restricted to a chalkland habitat. It can occasionally wander away from the downs by natural dispersal in good breeding years.

(male)

(female)

(mating)

Adonis Blue (Polyommatus bellargus)

This species is not to be found away from the downs and is reliant on a habitat of short chalkland sward.

(male)

(female)

(mating)

Holly Blue (Celastrina argiolus)

This is our earliest blue to appear in the spring and can be seen from late March, flying rapidly along garden hedges, roadside hedgerows and woodland edges.

(male)

(female)

(mating)

Long-tailed Blue (Lampides boeticus)

A common butterfly in Europe and beyond, this species has always been a rare migrant to Britain. In 2013 large numbers arrived in southern England along a broad front and produced a British brood during late summer and early autumn. It is now becoming a more regular migrant to our shores.

(male)

(female)

Small Blue (Cupido minimus)

This is our smallest British butterfly. In Sussex, it is predominantly a chalk downland species, occurring in small isolated colonies.

(male)

(female)

(mating)

Silver-studded Blue (Plebeius argus)

This attractive butterfly is a heathland specialist. In East Sussex, it only occurs in small isolated colonies on Ashdown Forest.

(male)

(female)

(mating)

Brown Argus (Aricia agestis)

This species occurs on chalk downland but can also be found in suitable habitat along field and woodland edges.

(male)

(females)

Hairstreaks in Sussex

The Hairstreaks have always held a fascination for me. They are an attractive group of butterflies within the Lycaenidae family and you need to hone your fieldcraft skills in order to find and get close to them.

 All five species of British Hairstreaks can be found in Sussex. Two of them are common and widespread within the county, two are much more localised in their distribution and one is in the county probably as a result of an unauthorised introduction.

Green Hairstreak (Callophrys rubi)

This lovely species is common and widespread in Sussex and can be found in a variety of habitats. Unlike our other hairstreaks, it is not really a canopy dweller and can invariably be spotted at head height along woodland rides, gorse patches on the downs and on heathland.

(male)

(mating pair, male on right)

(female)

(male)

Purple Hairstreak (Favonius quercus)

Another common and widespread species in Sussex, quercus is predominantly a woodland canopy dweller. However, it can be found and approached with stealth, low down along woodland rides at certain times of the day. 

(females)

(mating)

(males)

(female, ab. flavimaculatus)

Brown Hairstreak (Thecla betulae)

This species is predominantly a butterfly of West Sussex and rather localised in its distribution. For a species that lays its eggs on Blackthorn, a very common plant throughout Sussex, only occasional sightings are reported from East Sussex.

(all photographs are of females)

White-letter Hairstreak (Satyrium w-album)

This species is very localised in its distribution in Sussex. It lays its eggs exclusively on species of elm and colonies have been greatly affected by Dutch Elm Disease. Certainly, in my part of East Sussex, many fine elm stands have disappeared and sucker regrowth never looks very healthy after a couple of years. Consequently, finding colonies can be difficult.

(female)

(males)

Black Hairstreak (Satyrium pruni)

Nationally, this species occurs in a band across the English midlands, roughly between Oxford and Cambridge. Historically, it is unlikely that the Black Hairstreak has ever been native to Sussex but it is a species that has been subject to un-authorised releases in south-east England over many decades.

In 2017, a colony was found to be quite well established at a site in mid-Sussex.

My only encounter with the Black Hairstreak was in 2014, at a site in Cambridgeshire.

(female)