This rare polyamorous bird of prey’s location has been kept a mystery. Here’s why

A Single Male Harrier Is Holding Back Extinction in Britain — and Nobody Knows Where He Lives

Sandego.net – For six years, the United Kingdom went without a single new Montagu’s harrier family. Then, in 2025, one adult male broke the silence. Now, in 2026, that same bird has done it again — producing six young across two separate nests, each raised with a different female. Conservationists are calling the feat extraordinary, and they are deliberately withholding the location from public view because the species is so fragile that even a casual footstep near the nest could undo years of fragile recovery.

The bird at the centre of this story is an adult male identified by the ring code AU. He was fitted with a leg ring as a chick in 2016, in a region of the country far removed from where he now breeds. At the time, nobody could have predicted what that small, tagged juvenile would become a decade later.

“When we ringed him as a chick in 2016 in a different part of the country we had no idea that ten years later he would single-handedly prop up the species in Britain,” said Mark Thomas of the Royal Society for the Protection of Birds (RSPB).

From Red List to Reluctant Comeback

Montagu’s harriers — lean, long-winged raptors sometimes called the “aristocrats of the bird world” for their elegant flight — were placed on the UK’s red list of birds at greatest risk in 2021. Between 2020 and 2023, no breeding pairs were confirmed anywhere in Britain. The species had effectively vanished from the national breeding map.

The historical arc is stark. According to data compiled by the British Trust for Ornithology (BTO), the UK breeding population once reached roughly thirty pairs in the mid-1950s. By 1974 that number had collapsed to zero. A slow, uncertain recovery pushed the count back up to as many as thirteen pairs by the late 2000s before the species again slipped toward disappearance.

AU’s contribution since 2018 now totals at least sixteen chicks. In 2025 he raised four young with one female. This year the tally jumped to six juveniles, split between two nests, each associated with a different mate. The polyamorous arrangement — one male, two females, two sites — is unusual even among raptors and underscores just how much the species’ survival in Britain currently hinges on a single individual’s reproductive output.

The Mystery of the Hidden Nests

The RSPB has gone to considerable lengths to keep the breeding sites anonymous. The organisation describes Montagu’s harriers as a “sensitive species that is easily disturbed,” and notes that the birds may return to the same plots year after year. Publicising the coordinates, even in a news story, could invite walkers, photographers, or curious neighbours whose presence might cause the adults to abandon the chicks.

Both nests sit on private land. One was discovered inside a strip of barley that a local farmer deliberately left standing as habitat cover. The second nest lies less than a mile from the first. The sustained cooperation between the charity, local farmers, and a small circle of birdwatchers who agreed to keep quiet is credited with making this year’s success possible.

First-Time Satellite Tags on Juvenile Harriers

In July, fieldworkers from the RSPB fitted one chick from each of the two nests with a satellite tracking device. This marked the first occasion on which juvenile Montagu’s harriers have been tagged in the United Kingdom. The data will allow researchers to follow the young birds’ autumn migration south to Africa and monitor their first-winter survival — information that has been almost entirely absent from the species’ UK conservation record.

Each spring, adult “Monties” migrate from their African wintering grounds northward into Europe to breed. Only a small fraction of those migrants make it to Britain, and AU’s arrival in early May this year was met immediately by his courtship displays.

Skydancing and the Logistics of Two Nests

The aerial courtship of Montagu’s harriers is among the most visually dramatic in the raptor world. An RSPB spokesperson described the displays as featuring “high-altitude dives, rhythmic ‘U’-shaped undulations, loops, and twists accompanied by rapid, cackling vocalizations.” The behaviour, colloquially termed “skydancing,” is both a territorial signal and a mate-attraction performance.

Managing two simultaneous nests demanded considerable effort from the male. The spokesperson noted that AU “pulled off the two nests through hard work and a good food supply,” a remark that highlights the species’ dependence on abundant small prey — typically voles, mice, and small birds — in the surrounding farmland.

Why Secrecy Matters for a Species on the Edge

The decision to withhold the nest locations is not mere caution; it is a core element of the conservation strategy. A species that breeds in only one or two pairs across an entire country has no demographic buffer. A single disturbance event — a dog off-leash, a drone buzzing overhead, a viral social-media post pinning the GPS coordinates — could eliminate the last active breeding sites for another decade.

The collaboration model that produced this year’s chicks, pairing the RSPB’s monitoring expertise with farmers willing to leave habitat strips and birdwatchers willing to observe quietly from a distance, now represents the most realistic pathway to stabilising the UK population. Whether AU will continue to breed in Britain, and whether additional pairs will arrive from continental Europe in coming years, remains an open question. For now, the fate of the country’s rarest raptor rests on one polyamorous male, two hidden nests, and a promise to keep quiet.