Eight thousand birds are netted and ringed here every year. Each one is held gently, identified, weighed, measured, fitted with a tiny aluminium ring carrying a unique number and a return address, and then released to continue whatever journey it was on - the next leg of a migration that might take it from Africa to the Arctic, or simply back to a hedgerow on the Llyn Peninsula it had stopped at to feed. Bardsey Bird and Field Observatory has been doing this since 1953. The island it sits on - Ynys Enlli to the Welsh, Bardsey to the English - is two miles off the western tip of Wales, and on the right day in the right weather, more migrating birds funnel through this small piece of land than almost anywhere else in Britain.
The observatory was established in 1953 by an unusual coalition: ornithologists from the West Midland Bird Club, members of the West Wales Field Society, and a handful of local people on Bardsey itself. The West Midlands club, based 150 miles inland, saw something special in this Welsh island. It was not just a place to count birds on migration - it was an opportunity to study the complex ecology of a small island in something like its entirety. Bardsey is two miles by less than a mile. You can walk every corner of it in a day. You can ring every nesting pair of every species, every season, for decades. That makes it one of the most thoroughly documented pieces of British coastline anywhere - a place where, if you wanted to know what was changing in the natural world over seventy years, you could ask exact and very specific questions and get exact answers.
Staff at the observatory undertake a daily census of birds throughout the year - logging every species seen, with a register kept and updated each evening. Spring and summer are the intensive seasons, when the breeding landbirds and seabirds are counted and the great waves of migrants pass through. Chiffchaffs, goldcrests and wheatears come first - small insectivores arriving early from Africa or southern Europe. Sedge warblers and willow warblers follow, then whitethroats, then spotted flycatchers. Some birds rest a day; some stay for the season; some are gone in an hour. The Manx shearwater colony on Bardsey is one of the largest in the world - between 26,000 and 30,000 pairs come ashore in the dark to nest in abandoned rabbit burrows. The ringing programme produces data that feeds into national and international migration studies. The observatory is one of two fully accredited bird observatories in Wales and one of twenty around the entire coast of Britain and Ireland.
The observatory is based at Cristin, a working farmhouse on the western lowland of the island. Visitors can stay - it operates as a basic hostel, providing simple accommodation for birdwatchers, students, and anyone willing to live for a week with no easy way back to the mainland when the wind comes up. Steven Stansfield has been the Warden and Director of Operations since January 1998, the longest-serving member of staff the observatory has ever had. He has watched the island's bird populations through a quarter of a century of changing climate, changing land use, changing migration patterns. The data sits in the observatory's records. Some species are doing well. Some are not. The story is in the numbers, accumulating year by year, ring by ring.
Bardsey is layered with conservation status. It is a National Nature Reserve, a Site of Special Scientific Interest, a Special Protection Area, an Environmentally Sensitive Area, part of the Llyn Peninsula Special Area of Conservation, and part of the Llyn Peninsula Heritage Coast - and it sits inside an Area of Outstanding Natural Beauty. Every plant, lichen and bird here is, in some category, protected. The Bardsey Island Trust owns the land. The Royal Society for the Protection of Birds held the sheep-farm tenancy for many years; the management has changed but the principle has not. This is a small piece of the Welsh coast that has, by deliberate human choice, been turned into something close to a permanent natural experiment. The birds keep coming. The observatory keeps counting.
Bardsey Bird and Field Observatory is located at Cristin on the western lowland of Bardsey Island, approximately 52.76 degrees north, 4.79 degrees west, in the southwest portion of the island. Bardsey itself lies 2 miles off the southwestern tip of the Llyn Peninsula. From the air the island is unmistakable - a long, hill-topped shape with a low western plain and a red-and-white striped lighthouse at the southern tip. Approach with caution: this is a major migratory bird route and a National Nature Reserve. Avoid flying low over the island, especially during breeding season (March to August). Nearest airports: Caernarfon (EGCK) 35 nm northeast, Valley (EGOV) on Anglesey 35 nm north-northeast. Bardsey Sound is notorious for currents and changing weather; the same can affect aircraft as wind shear around the headland.