Country diary: self-sufficient ponies open up the wetlands for wildlife

Waltham Brooks, West Sussex A burst of loud, profane whistles announce the presence of a Cetti's warbler, darting through the rushes in search of food

The early morning rain has lifted but there is still damp in the air. Konik ponies watch me between their mouthfuls of grass as I make my slow way through the dark, water-logged mud. The small, brown horses - descendants of the wild Tarpans that once roamed Europe - are a hardy, self-sufficient breed, perfectly adapted to grazing wetlands. They are used increasingly by conservation bodies in the UK, as here by the Sussex Wildlife Trust, to control young trees, shrubs and plants that would otherwise grow and dominate habitat like this. The ponies' grazing clears channels and pools, opens up patches of grass, and creates new opportunities for diverse species of plants, insects, birds and animals to thrive.

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