A search for the elusive Large Heath Caterpillar on Thorne Moors

16 April 2026 from 9am to 4pm

Join us for a hands‑on field survey exploring the larvae that feed on cottongrass in Thorne’s wetland habitats. The work will involve wading through damp areas in wellies and carefully inspecting hare’s‑tail cottongrass tussocks, where the larvae can be found high in the plants during daylight hours. Please bring wellies and a packed lunch, as we’ll be out on site for an extended period.

Recent adult surveys have shown a marked decline in population densities across the southern canals and other parts of south Thorne over the past decade. In contrast, the species has begun to establish itself in the revegetated milled peat areas in the north. As part of this visit, we aim to explore ways of developing a robust sampling method to compare larval densities between these contrasting habitats.

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