Castor Hanglands Nature Reserve near Peterborough has the most diverse freshwater invertebrate fauna of any pond surveyed in Britain by Freshwater Habitats Trust.

This wonderful site also supports several of Britain’s most endangered freshwater plants and animals, including Great Crested Newts Triturus cristatus, delicate plants like Lesser Water-plantain Baldellia ranunculoides and Tubular Water-dropwort Oenanthe fistulosa, Floating Bur-reed Sparganium angustifolium and a primitive group of plants called stoneworts which have been around since dinosaurs roamed the Earth.

Castor Hanglands is an oasis of green in an intensively farmed landscape. Walk amongst its ancient woodlands with their medieval boundary banks and commons still showing their 700 year old cultivation ridges, and you are stepping back in time to a world now almost gone. The ponds nestled within Castor Hanglands are a miraculous survival of the history of the British countryside. They remain free from the pollution and intensive land use which has eliminated much of our freshwater wildlife from the rest of the lowland England.

The main pond at Castor Hanglands has been monitored by a local volunteer since the early 1970s.

To date, just under 100 aquatic plants have been recorded from this one pond. The pond is also incredible rich in insect life, a total 134 species of invertebrate recorded in one year, compared to the average for a ‘normal’ good pond of around 50-60 species. The rarities and the overall species richness of the pond are indicators of the very best freshwater habitats now lost from large parts of the countryside.

The Flagship Ponds project has provided funds for a much needed professional re-survey of the main pond, and surrounding ponds for invertebrates which will help to inform management. We have also undertaken emergency work to minimise the risk of invasive species spreading and threatening the richest pond. Enthusing local people and site visitors about this remarkable site though walks, talks and a new interpretation panel, will help to explain the significance of the pond and we hope will inspire future generations to care for it.