Osprey breeds again in Switzerland – for the first time in over 110 years

Eleven years after the launch of a reintroduction project, an osprey pair has settled to nest in Switzerland, for the first time since 1914.

In spring 2026, three chicks hatched in the Three Lakes region. The news was deliberately withheld so as not to disturb the peace of the brood.

A species that vanished through poaching

For over a century, the osprey was considered extinct as a breeding bird in Switzerland. Wendy Strahm, coordinator of the project run by the western Swiss bird protection association «Nos Oiseaux», confirmed to the news agency Keystone-SDA that the last documented reproduction of the species dates back 112 years. After that, the osprey vanished as a breeding bird from Switzerland; on migration, the species continues to be observed regularly. The species disappeared following intensive human persecution, including shootings and egg theft.

This story fits a pattern that also affects other native predators: species that were once exterminated through targeted persecution and were only able to return decades later thanks to elaborate protection programmes. With wolf and lynx too, it becomes clear how strongly the pressure of human persecution can shape the population of native wild animals over generations.

How the comeback succeeded

The «Nos Oiseaux» association launched the reintroduction project in 2015, the year of its 100th anniversary. The first six young birds came to Switzerland as a gift from the Scottish government, with further birds following from Norway and Germany. Between 2015 and 2020, the association imported a total of 66 osprey chicks. They grew up in aviaries without direct human contact on the agricultural grounds of the Bellechasse penitentiary near Sugiez FR, before taking their first flight.

This so-called translocation method exploits a biological reflex: with a wingspan of up to 170 centimetres, the site-faithful osprey instinctively returns after reaching sexual maturity to the region where it fledged, in order to nest there itself. The method was scientifically underpinned in a joint baseline report by the Swiss Ornithological Institute, BirdLife Switzerland and «Nos Oiseaux», which aligned the osprey's reintroduction with the model of earlier species-conservation projects: after the white stork, brought back in the 1950s, and the bearded vulture in the 1990s, the osprey is the third species to return to Switzerland in this way.

The undertaking was not uncontroversial at the outset. Nature conservation organisations such as Pro Natura and BirdLife Switzerland originally argued for awaiting a natural recolonisation by ospreys migrating in from France, since the nearest breeding sites lay only around 200 kilometres away. «Nos Oiseaux» opted for active translocation, drawing on decades of experience with this method in other European countries.

In 2018, the male «Fusée» achieved the first documented return of a released young bird to Switzerland, at that time still without reproduction. Those responsible for the project put the population size needed for success at a minimum of 60 released birds, a threshold that is now passing its acid test with the current brood. The first successful brood is a key milestone. Whether a long-term self-sustaining population will establish itself will only become apparent in the years to come.

That is precisely what has now happened. The male of the breeding pair is from the 2020 cohort and, thanks to a numbered blue ring, is clearly identifiable, as Denis Landenbergue of the project's steering group notes. The unringed female is of unknown origin. Both birds had already been sighted in the summer of 2025, though the female was not yet sexually mature at the time. After spending the winter separately in Africa, both returned and took up one of around thirty nesting platforms erected by volunteers in the Three Lakes region.

Three young birds despite a cold spring

That the very first breeding attempt was successful is remarkable, particularly as the spring of 2026 turned out cold and rainy. According to Landenbergue, often not even the third chick survives. This time all three young birds — the two females Somone and Khnifiss as well as the male Diawling — made it through the rearing.

The next critical stage still lies ahead for the young ospreys: at the end of August their first migration to Africa begins, during which the mortality rate of young migratory birds statistically stands at around 80 per cent. If they survive the first migration and the overwintering, they could return to the Three Lakes region in about two years.

Context

The return of the osprey is a milestone for species conservation in Switzerland. For the first time in over 110 years, a pair has once again bred successfully. A permanently self-sustaining population is not yet secured, however: it will be decisive whether further returning birds find suitable, low-disturbance breeding sites and whether the three young birds survive their first migration to Africa. Precisely for this reason, the project shows how long-term and consistent species promotion must be — from reducing human persecution and protecting suitable habitats to safeguarding migration routes.