A rare and protected species of butterfly has been spotted in south Essex and work is taking place to preserve their habitat.

The Heath Fritillary butterfly, previously on the brink of extinction, is being welcomed and preserved through the efforts of Essex and Suffolk Water in collaboration with conservation charities.

Ashley Pinnock, Conservation Specialist at Essex and Suffolk Water, first identified the species at Oakwood Reservoir, in Hadleigh, three years ago.

With counterparts from Essex Wildlife Trust and the Butterfly Conservation team, Mr Pinnock discovered that the Common Cow-Wheat plant served as a food source for these delicate creatures.

He said: “I love butterflies and was working away one day when I saw a Heath Fritillary fly past me, and I couldn’t believe it.

“I immediately investigated what I could do to preserve and manage their habitat and in the past three years I’ve seen both male and female butterflies, but no caterpillars yet.

“Working with our partners we’ve learnt that the butterflies have been using Oakwood Reservoir as a stepping-stone between two woodlands, Pound Wood and Hadleigh Great Wood.

“It’s so important, because these are rare butterflies, with just a few remaining strongholds in Britain where they can be seen.

“Allowing them to migrate from one location to the next is important for their breeding and genetics, to ensure the future of the species.”

Living for only three weeks, these rare insects are generally spotted in May and June, though preparation to preserve their habitat for the upcoming year commenced in November 2023.

Since 2016, the quantity of Heath Fritillaries in Pound Wood, has grown from 40 to 120 sightings in 2021, while Hadleigh Great Wood, owned by Southend City Council, saw numbers rise from seven in 2016 to 75 in 2021, peaking at 148 in 2019.

Ruth Angrave, nature reserves manager for Essex Wildlife Trust, said: “This crucial piece of work will connect two populations of this enigmatic butterfly and provide a corridor for this and other species to move between two important woodlands.

“This work is a great example of the benefits partnership working can bring to species and habitats.”