The Wood White (Leptidea sinapis) is one of our rarest and most enchanting butterflies. It exhibits probably the slowest and most delicate flights, almost fairy-like, of all the British species. Its discreet colonies typically contain just a few dozen adults, though there are still a few locations, and seasons, when it can be a locally common springtime butterfly. Salcey Forest, near Northampton, was historically one of its strongest outposts. Today, only the much-reduced populations of the Chiddingfold Forest complex on the Surrey/Sussex border can be classed as 'large' – in a good season.
With conditions being almost perfect for finding and photographing this beautiful species, I recently headed into the Chiddingfold Forest complex. This season’s spring brood has emerged in the known hotspots about three weeks later than last year, and they are only being found in reduced numbers. Their principal colonies appear to be down by up to 75% over last year, with some areas of the forest producing only one or two individuals on a good day. The highest daily count to date, made by myself during my search, was 12 individuals from one of the most productive areas; though I feel sure that others were undoubtedly present away from the main tracks.