The hatching of hen harrier chicks at nests on a private estate for the second year running "gives hope for the future", the RSPB has said.
The charity said it found the hatchlings in four nests on the Bowland Estate in Lancashire's Ribble Valley.
Project officer James Bray said as hen harriers were in severe decline, the birds had been "closely" monitored.
The total number of chicks was unknown, but it was hoped there would be more than the 13 born in 2018, he added.
The beauty spot used to be known as England's last remaining stronghold for breeding hen harriers but 2018 was the first time they had nested since 2015.
The RSPB said the bird of prey was "on the edge of extinction in England", adding that there were only 617 reported breeding pairs across the UK.
"We were delighted last season when birds successfully nested after two disappointing years, but we were fearful it might have been a one-off as the population remains perilously low," Mr Bray said.
"Last year, we saw 13 chicks fledge at Bowland; perhaps this year we might have even more."
The charity and estate owner United Utilities have asked visitors to the area during the breeding season, between late March and early September, to stick to tracks and footpaths to avoid disturbing ground nesting birds.