Osprey breeds in Switzerland for the first time in 112 years

For the first time since 1914, a pair of ospreys has bred successfully in Switzerland. The eggs hatched between 25 and 29 May and three chicks were born. The news was kept confidential until now to give the brood peace, and has been released to Keystone-ATS by Wendy Strahm, coordinator of the reintroduction project run by the association Nos Oiseaux.

The nest is in the region of the lakes of Neuchâtel, Biel and Murten. Its exact position will not be disclosed.

The species had vanished entirely from Switzerland's breeding birds because of poachers and egg collectors. It could still be seen in flight during migration, but it no longer bred here.

A project built on an instinct

The reintroduction rests on a trait of the bird: the osprey shows breeding philopatry, meaning that on reaching adulthood at around three or four years old it returns to breed in the area from which it first fledged.

Between 2015 and 2020 the association imported 66 chicks taken from nests, mainly in Norway and Germany. They were raised in aviaries near Sugiez, in the canton of Fribourg, without any direct contact with humans. This translocation method has been used elsewhere in Europe since 1996.

The male of the pair is one of those chicks: he carries a numbered ring and left Sugiez in 2020. The female is unringed and her origin is unknown. The two had already been spotted in the summer of 2025, when the female was still immature. After a winter spent separately in Africa they returned and settled on the nest identified the previous year, one of thirty platforms set up in the region by volunteers. The first egg was laid on 19 April.

Succeeding at the first attempt is exceptional, all the more so in a cold, wet spring. "The third chick often dies," notes Denis Landenbergue, of the group that ran the reintroduction. Here two females and a slightly frailer male survived. They now weigh between 1.4 and 1.8 kilograms and have reached the adult wingspan of 152 to 167 centimetres. They were ringed on 6 July.

Within the pair the male fishes and the female does everything else: incubating, watching over the nest and feeding the young. "The female also shielded the nest from the sun during the heatwave, spreading her wings like a parasol," Strahm says.

The hardest test comes now. By the end of the month the young birds will set off for Africa, and statistically the mortality rate for migrants on their first journey reaches eighty per cent. Those that survive should return to the three-lakes region within two years.