Hundreds of the tiny small blue butterflies have been on the wing this spring at RSPB Winterbourne Downs. This is thanks to conservation works funded by the SITA Trust and the Heritage Lottery Fund via the Magnificent Meadows project.
Scrub has been cleared from two areas of south facing railway embankment, and an innovative 150m long south-facing “S” shaped butterfly bank dug out of the chalk in one of the nature reserve’s fields. These designer homes and other suitable light chalky soils around the reserve have been planted with kidney vetch, the favoured food plant for small blue caterpillars. Volunteers have been also busy over-winter and spring planting out seed and plugs of wildflowers favoured for egg laying and nectaring by chalk downland butterfly species, such as the brown argus, chalkhill & Adonis blue and the marsh and dark green fritillary butterflies.
In late May I was astonished to count 106 small blue butterflies along one field margin, and have now seen them over 2km away from the original colony. It has been especially rewarding to see them on the new chalk banks designed to give them a home. The small blue often has a second brood which will be on the wing in mid-August, so do keep your eyes peeled if you are visiting the reserve later this summer.