Large Marsh Grasshopper
Stethophyma grossum
Tap image to enlarge · Wikimedia Commons
Overview
Britain's largest grasshopper and one of its rarest. The Sefton Coast is one of a small number of sites in England where the Large Marsh Grasshopper can be found, making it a genuinely special species to see. It lives in wet sphagnum moss and rush beds in the dune slack system. The call — a series of ticks rather than a typical grasshopper chirp — is distinctive. Males are brownish with a yellow-striped abdomen; females are larger.
At a Glance
| Order | Orthoptera |
| Family | Acrididae |
| Habitat | Wet dune slack · Sphagnum bog · Rush beds · Boggy heath |
| Diet | Grasses, sedges, rush leaves |
| UK population | Nationally rare — restricted to a handful of wet heathland and dune slack sites in England |
| Sefton Coast | One of the most important populations in England; Ainsdale NNR is a stronghold |
| Conservation | UK Amber List |
Where to See It
Wet dune slacks and boggy areas at Ainsdale NNR. Specific to wet Sphagnum and rush habitats.
Identification
Britain's largest grasshopper, to 40mm. Mottled brown and yellow. Red and yellow underside to abdomen visible from below. Ticking call rather than chirp — like a finger nail flicked against a comb.
Viewing & Photography Tips
Walk the wet slack areas at Ainsdale in August. Listen for the ticking call from wet grass and rushes. They are well-camouflaged but often bask on rush stems in sunshine.
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
Why is the Large Marsh Grasshopper so rare?
The Large Marsh Grasshopper is restricted to wet, boggy habitats — Sphagnum-dominated dune slacks, wet heathland and valley bogs — which have been drained or destroyed across most of England. The remaining populations are fragmented and small. Ainsdale NNR is one of a handful of English sites with a viable population, making it a nationally important conservation site for this 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.