Photographs show two stallions rearing up on their hind legs and sparring with each other at a nature reserve.
The Konik ponies, a hardy breed originating from Poland, were brought to the National Trust’s Wicken Fen reserve in Cambridgeshire in 2001 to help biodiversity.
The grazing animals help create habitats for other species, leaving water-filled hoof prints and piles of dung as they move around the lowland landscape.
During the foaling season, male Koniks can engage in sparring, which is part of their natural behaviour and has been seen at the reserve in recent years.
The displays of dominance tend to dissipate quickly with very few injuries.
Last year the National Trust recorded a rare type of moth as the 10,000th species at Wicken Fen.
The six-belted clearwing mimics the appearance of a wasp to avoid predators, with a striped yellow abdomen.
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