New-to-Britain insect discovered in hidden Norfolk wetland

A moth called enchanter’s mompha, a species of silver fly never before found in Britain, and the endangered (and huge) fen raft spider have all been discovered in one of Norfolk’s most tranquil, and hidden, wildlife havens.

Despite having a railway halt nearby, and thousands of internationally-famous inhabitants arriving every winter, Buckenham Carrs, in the Yare valley between Reedham and Brundall, is part of a private estate and barely known to most Norfolk people. Trains on the Wherry line only pause at the isolated request stop at weekends, and the most famous residents are crows – tens of thousands of them gather at Britain’s largest rook roost every winter.

Two herons perch above Hassingham Broad in the Buckenham Carrs (Image: Archant 2022)

A greylag goose runs ready to fly across Buckenham Broad (Image: Archant 2022)

One of the dykes leading from Buckenham Broad to Hassingham Broad (Image: Archant 2022)

Now the woodland, water and grazing marshes stretching along the Yare valley between the hamlets of Buckenham and Hassingham, is giving up some of its secrets.

The first detailed survey of its wildlife has revealed some of Britain’s rarest plants, animals and fungi living just a few miles from Norwich. For three years volunteers from the Norfolk and Norwich Naturalists Society (NNNS) have painstakingly searched out mosses and ferns, found hundreds of species of flowers and fungi, trapped moths and identified insects.

They found more than 1,600 species of plant, animal and fungi – including many which are rare and endangered - and some which have never been recorded in Norfolk before.

The magical-named enchanter’s mompha moth, whose larvae eat enchanter’s nightshade, was discovered alongside rare wetland plants including milk-parsley, marsh fern, water soldier and holly-leaved naiad.

The naturalist volunteers found Buckenham Carrs is home to a vast array of wildlife from marsh fern and whorled water-milfoil to dented silk-moss, bonnet fungi, the rare large-mouthed valve snail, great silver water beetle and the hedge cosmet moth. They uncovered a very rare species of spider-hunting wasp, nesting beneath the decking of a cottage, and, in reedbeds, Britain’s first recorded example of the Leucopomyia palliditarsis silver fly.

Dr Mark Collins, chair of the Norfolk and Norwich Naturalists Society research committee, said thousands of hours of voluntary work had revealed the wildlife teeming through the waterlogged, wooded world of Buckenham Carrs. “Together, they represent an extraordinary and delicate web of life that must be nurtured and protected with great care. Much work remains to be done and there will continue to be rich rewards for the naturalists that follow on from this ground-breaking project.”

Dr Mark Collins, chairman of the Norfolk and Norwich Naturalists' Society, out in Buckenham Broad. The NNNS has recently completed a survey of the wetlands, woodlands and grazing marshes around the Buckenham Carrs (Image: Archant 2022)

Highlighting the discovery of the predatory silver fly, by Dr Tony Irwin, he said: "Silver flies are used to control scale insects in forestry and horticulture in various countries. Who knows when this one might be able to help us control a pest in the UK? Without the work NNNS did at Buckenham Carrs no one would know this potentially useful creature was ever there..."

Experts believe there are many more species waiting to be discovered at Buckenham Carrs, but Mark said they depend on a continuous supply of clean fresh water to spring-fed Buckenham and Hassingham Broads. “Brackish water from higher tides in the Yare, or nutrient-rich water from arable fields, could be disastrous,” he said.

The naturalists used small boats to navigate the 340 hectares of marshes and dykes and reveal the richness of the wildlife of privately-owned Buckenham Carrs. It is part of the Buckenham and Hassingham Estate and includes parts of two Sites of Special Scientific Interest, managed with support from Natural England.

Every winter up to 50,000 rooks roost here in Britain’s biggest nocturnal winter rookery. Norfolk conservationist and wildlife writer Mark Cocker was mesmerised by the sight of tens of thousands of birds whirling through the winter dusk to settle in the trees, writing about it in his acclaimed book Crow Country.

Osprey, marsh harrier, bittern and even a white-tailed eagle have also been seen at Buckenham Carrs.

To see a similar landscape of marshes, reedbed, wetland and valley, which is open to the public and also brimming with hundreds of species of plants and animals, visit the neighbouring RSPB Buckenham Marshes nature reserve.