RSPB Nagshead:, a quiet nature reserve in the Forest of Dean

As sunlight breaks through the leaves of old oak trees on a crisp, late-spring morning, the melody of the dawn chorus fills the air – the song of the woodland. Bluebells dot the grass, a vivid splash of colour against the green glade. The beat of a woodpecker drumming on a tree carries over the air. RSPB site manager, Lewis Thomson, has been working here for 14 years, and feels as though this special place could be the middle of a wilderness in eastern Europe, but it is in fact RSPB Nagshead, a quiet nature reserve in the heart of the Forest of Dean, just 20 miles from Gloucester.

Nagshead is owned by Forestry England, but the RSPB has leased and managed the site for nature since the 1970s. The reserve has always been a haven for spectacular wildlife, including many of our much-loved woodland birds. Much of the reserve is mature oak woodland, with the trees being planted for timber during the Napoleonic wars over 200 years ago. The elusive hawfinch, Britain’s biggest finch, is a lucky spot and summer sees the striped tree pipit hop among the leaflitter in the open woodland. Nightjars churr in more open areas, and small redstart are a pop of colour in the canopy. Butterflies drift in the summer heat and lucky visitors may even spot native reptiles darting around in the undergrowth. A brilliant example of Nagshead’s wildlife story is that of the striking pied flycatcher, a small bird who returns here in the spring.

Bluebells at Nagshead reserve. Photo: Lewis Thomson In the 1940s, Forestry Commission, now Forestry England, noticed caterpillars munching the leaves of young trees in the nursery. A simple solution was to install nest boxes to attract birds to eat the caterpillars. Nagshead now has 410 trees with nestboxes, and one of the most notable birds to benefit was the pied flycatcher – a small, black-and-white flycatching bird, slightly smaller than a house sparrow, which migrates here from West Africa in summer to breed.

By the early 1990s, 100 pairs of pied flycatchers were using the boxes. This 80-year nest box scheme has provided one of the longest-running sources of data on this species: teaching us about changes and fluctuations over time, particularly their fledging success rates, clutch sizes and when they lay their first egg. All this information is invaluable in monitoring population changes and responses to climate change.

Adult male pied flycatcher at Nagshead. Photo: Lewis Thomson Unfortunately, pied flycatcher have seen national declines and are now an amber listed bird. In the UK, they have declined by 42% in the last 22 years. In 2024, only 22 pairs used the nest boxes.

‘The research on why we’re seeing such declines is ongoing,’ says Lewis, ‘and we don’t yet fully understand the reasons. It could be that climate shifting means caterpillars emerge earlier, meaning there is not the abundance of food around at a crucial time when pied flycatchers need to feed their young. There is also evidence of changes on their wintering grounds which may be impacting them, but it’s not an easy picture and it’s likely there’s a multitude of factors involved.’

Nonetheless, RSPB staff and volunteers continue to have hope, and work hard carrying out vital conservation work to help slow the decline of pied flycatchers, and many other woodland species. It’s not an easy job but it is rewarding, as Lewis explains: ‘I trained in graphic art and design but found myself in what felt like a dead-end job in retail, working indoors all day, under artificial lights. I knew I wanted a change.

Adult nightjar, roosting. Photo: Andy Hay/rspb-images ‘I have always felt drawn to nature, and have been mad about birds since I was tiny; I especially love woodlands. I moved to the Forest of Dean and did an ecology-based degree and started volunteering with the RSPB in 2008 at Nagshead. I got the lucky opportunity to become an assistant warden in 2011. In 2020 I was successful in getting the role of site manager, so I’ve worked here a relatively long time. Woodlands are a slow-moving habitat – you need a long time to get to know them and to understand how things change and react. Having that experience here means I better understand what we need to do to make the biggest positive impact for nature.’

Lewis also manages RSPB Highnam Woods, an ancient woodland between the Forest of Dean and Gloucester – a gem for wildflower lovers, where nightingales return in spring to breed in the coppice, and home to cuckoo flowers, wood anemones, and a rare plant called Tintern spurge. The RSPB team works hard to improve the site, by removing non-native trees and creating a woodland made up of trees of different ages and abundant decaying wood. They create open areas to let warm sunshine in and give woodland species that prefer open spaces the chance to thrive.

Common nightingale in song. Photo: David Tipling/rspb-images However, Lewis and his team could not do what they do without the help of volunteers. ‘Most volunteers are local and are the backbone of our conservation work,’ he says. ‘A shining example of this is the nest box checks. From April until birds fledge in June, volunteers work hard to inspect all our nest boxes. It is crucial work that helps give us an insight on the changing fortunes of breeding birds and monitor numbers. We are immensely grateful for them giving their time to help us protect nature.’

Habitat work to improve oak woodland for pied flycatcher and redstart is an ongoing labour of love. These birds like old-growth open woodland and so the RSPB team is busy thinning out dense stands of holly to ensure it doesn’t dominate the forest floor. There’s hope for young oak to grow, especially in the glades. Natural England has funded 12 trial enclosures throughout the SSSI (Site of Special Scientific Interest) oak woodland to help keep nibbling deer and boar from damaging young oak regeneration. The trial also includes deploying 500 ‘cactus guards’ around individual young oaks. These mesh tree guards have small spikes and are usually installed to deter livestock from damaging them: the hope at Nagshead is that they will prove effective at deterring the resident boar population.

Adult male redstart, Forest of Dean, Gloucestershire. Photo: David J Slater/rspb-images Conservation may be work for Lewis, but that doesn’t take the magic away from Nagshead for him: ‘I’m lucky to witness things that people may not think you can experience in the UK. We have so much nature to celebrate, you just need to go out and connect with it. One of my favourite things is seeing the delight visitors get at discovering some of our more enigmatic species. It’s so rewarding to help people on their journey to care about nature in the UK.’

Nagshead has two wildlife hides – the Lower Hide and Campbell Hide – overlooking peaceful woodland pools and providing the perfect spot to watch nature at its best. The Lower Hide is ideal for spotting redstarts and pied flycatchers busy feeding around the ponds. The visitor centre, which has toilet facilities, is open on weekends and bank holidays from April to September, 11am to 3pm.

The reserve is beautiful year-round: buzzing with life in spring and summer, bright with autumnal colours come October, and ending the year with the bare cathedral-like trees set against the winter sky.

Adult male hawfinch (Coccothraustes coccothraustes) Forest of Dean, Gloucestershire. Photo: Ben Andrew/rspb-images ‘Spring is my favourite time of year here,’ says Lewis, ‘it’s simply stunning at dawn, among the bluebells whilst listening to the spectacular dawn chorus – there’s no better place to be.

‘Even our visitor centre is great for wildlife – we get plenty of birds nesting in the building and roof. We’ve even had great tits nesting in the ladies’ toilet window, and pipistrelle bats roosting behind the cladding – it’s never a dull moment here amongst the wildlife!’

Find out more about Nagshead and plan your visit here: rspb.org.uk/days-out/reserves/nagshead. The carpark is open from 8am until dusk with seasonal variation, please check before visiting.