‘You have to disguise your human form’: how sea eagles are being returned to Severn estuary after 150 years

Sea eagles were last seen soaring over the shimmering mud flats and brackish tidal waters of the Severn estuary more than 150 years ago. Now wildlife charities have unveiled innovative plans to bring the raptor back to the estuary, which flows into the Bristol Channel between south-west England and south Wales, by 2026.

"Sea eagles used to be common in these regions. But they were wiped out through human persecution," says Sophie-lee Williams, the founder of Eagle Reintroduction Wales , which is leading the project. "We strongly believe we have a moral duty to restore this lost native species to these landscapes."

Britain's sea eagles, which have a wing span of up to 2.4 metres, were shot and poisoned by landowners until the early 20th century, with the last known native eagle shot in Shetland in 1918. However, birds from Norway were brought to Scotland in the 1970s and 1980s and there are now estimated to be 152 pairs across the country. Some of the Scottish birds were released on the Isle of Wight in 2019, with three eaglets successfully reared by their parents so far.

The project team is testing the possibility of collecting younger birds from Norway so they can be released earlier, which they believe will help the adolescent eagles settle and survive in the wild.

However, rearing younger birds in captivity runs the risk of the eaglets imprinting on humans, which could lead to them seeking out people rather than avoiding them in the wild. To guard against this danger, the handlers will wear long robes and feed the young eagles chopped rabbit and other meat with bird hand-puppets.

"You can look after [white-tailed eagles], but they can never see you. You have to disguise your human form at all times," says Eric Heath, a species recovery expert at the wetlands restoration charity WWT, who is in charge of bringing the eagles to the UK.

Britain is one of the most nature-depleted countries in the world, with one in six species currently threatened with extinction. Williams hopes that restoring eagles to the top of the food chain in the estuary will create a more balanced, thriving ecosystem.

Sea eagles usually eat the most commonly available fish and waterfowl in their habitats, which gives opportunities to struggling, threatened species. "Eagles reduce direct competition from other fish for protected species like salmon and brown trout," says Williams. "They also reduce predation on them by predating on the birds that eat the salmon smolts [young salmon who are adapting to salt water]."

However, not everyone has welcomed the return of eagles to Britain's skies. In Scotland, farmers have complained that eagles have taken livestock , and the National Farmers' Union opposed a now-abandoned plan to release sea eagles in Norfolk.

Williams has held dozens of public meetings about the project and taken captive sea eagles to eight agriculture shows in Wales . While the response has been mostly positive, she has had to address concerns about livestock being taken by the eagles.

"There is no evidence that sea eagles take healthy, viable lambs [in Scotland]. But there is evidence of them scavenging [dead or dying] lambs," she says.

A recent study found that lambs make up only an average 6% of the remains recovered in sea eagle nests in Scotland. "Some farmers seem to think we are releasing this pterodactyl into the landscape, and they're going to come and eat their breeding ewes," she says. "That is just not the case at all. The average of their prey weight across Europe is between 0.5kg and 3kg."

Williams has also dealt with concerns about the risk to cats, dogs and even children: no pet collars have been found in eagle nests: "Your pets and children are safe! They are more scared of you than you are of them."

All the eagles will be satellite-tagged so the project team will be able to investigate any allegations that they have harmed livestock. The tags will also allow the project team to keep the birds safe; released eagles have died in illegal poisoning incidents linked to shooting estates.

Williams, who grew up in the south Welsh valleys, longs for the day when she can watch eagles swooping in the skies above her home. "They are so majestic. If you see one, you never forget that experience," she says. "They are such an iconic and charismatic species."