Silver-studded Blue
Plebejus argus
Tap image to enlarge · Wikimedia Commons
Overview
The Silver-studded Blue is one of the more special butterfly records for the Sefton Coast, associated with the dune heath habitat where Heather grows. Males are a vivid violet-blue with a distinctive silver-studded underside hindwing; females are brown with orange spots. They live in colonies and tend not to travel far, making habitat management critical. The Ainsdale NNR heath management benefits this species.
At a Glance
| Order | Lepidoptera |
| Family | Lycaenidae |
| Habitat | Dune heath · Heather heath · Coastal heath |
| Diet | Adults: Heather, Bird's-foot Trefoil, thyme. Larvae: Heather, Bell Heather, Gorse |
| UK population | Declining nationally; strongholds on southern heathland and coastal dunes |
| Sefton Coast | Colony present in the heather areas at Ainsdale NNR; one of the more northerly sites in England |
| Conservation | UK Amber List |
Where to See It
Dune heath with Heather at Ainsdale NNR. Found in colonies — specific to heathland habitat.
Identification
Small blue butterfly. Males: bright violet-blue with black border. Females: brown with orange marginal spots. Underside has distinctive silver-studded spots on hindwing — key feature.
Viewing & Photography Tips
Search the Heather areas at Ainsdale NNR in July. They tend to stay low, nectaring on Heather flowers. Visit in the morning when they are most active.
Conservation Status
UK Amber List
This species is of moderate conservation concern. Population monitoring and habitat management on the Sefton Coast support its continued recovery.
Frequently Asked Questions
What is the relationship between Silver-studded Blue and ants?
Silver-studded Blue caterpillars have a mutualistic relationship with black ants (Lasius niger). The caterpillars produce secretions from a dorsal nectary organ that ants collect, and in return the ants protect the caterpillars from predators. At pupation, ants may carry caterpillars into ant nests where they pupate. This ant-butterfly relationship is one of the reasons the Silver-studded Blue is so habitat-specific.
Related Species
Plan your visit to the Sefton Coast
Marshside RSPB, Formby pinewoods, Ainsdale NNR — practical guides to getting there, what to bring, and the best spots for each season.