A pair of hen harriers have successfully hatched four chicks, which have now fledged, in the South Lakeland area of the National Park.
The endangered birds nested on a livestock pasture which is part of a local shooting estate.
National Park Authority rangers have monitored the site since May, while police have also helped to protect the nest from poaching activity.
Two of the chicks have been tagged, meaning their future movements will be tracked.
Yorkshire Dales National Park Authority chairman Carl Lis said:
“It is a source of joy, and relief, that hen harriers have at last bred again successfully in the Yorkshire Dales National Park. These are magnificent birds, ideally suited to the Dales, and their long absence has shamed us all.
“Despite the brilliant news about the hen harriers, we shouldn’t forget that it has been only a few weeks since a red kite was found shot dead in the south of the National Park. I would urge members of the public to pass on any information they might have to North Yorkshire Police. Grouse shooting concerns, conservation bodies, the police and local wildlife groups must continue to pull together.”
Two hen harriers attempted to nest in the Yorkshire Dales National Park last year, but both attempts were thought to have failed because of natural predators.
In 2016, the number of breeding hen harrier pairs fell to just four - down from 12 in 2010 - in England, leading to fears they could die out completely. Scotland, Wales and Northern Ireland have higher populations.
Hen harriers are the most threatened birds of prey in the UK, with conservationists blaming illegal persecution as well as the historic destruction of vital heather moorland and forestry habitats. In North Yorkshire, five tagged hen harriers were reported missing between November 2016 and February 2017. They are unpopular in grouse shooting areas.