The South of Scotland Golden Eagle Project said the birds had thrived as people were told to stay close to home, with one named Beaky flying about 90 miles south to the Pennine Hills.
Since 2018, the project has successfully moved four golden eagles from the Highlands to the south of Scotland to boost the number of the raptors in that area.
But the group said the small population of “isolated and vulnerable” eagles in Dumfries and Galloway and the Scottish Borders are at risk of disappearing, and it plans to move more chicks next year.
Project manager Cat Barlow said: “One of Scotland’s most iconic wildlife species, golden eagles play a vital role in maintaining healthy local ecosystems in the south of Scotland.
“Two years after our first translocation, it is wonderful to see our first chicks thrive in the area and interact with locally fledged young eagles – this is absolutely key to addressing low numbers in the area before they are lost to the area forever.
“We were particularly excited by Beaky’s exploration into northern England, as she is the first of our birds to explore that far south.
“There have been no golden eagles breeding in the wild in England for a number of years now.
“The Covid-19 restrictions have unfortunately prevented us from doing everything that we would normally do this year, but we look forward to increasing the numbers again next year and for many years to come.”
Beaky made her furthest journey south around Easter and has ventured into England again since then, but not as far.
Before the conservation project began, there were only between two and four pairs of golden eagles across Dumfries and Galloway and the Borders. However, a study by Scottish Natural Heritage found the habitat is suitable for up to 16 pairs.
The project team has collected single eagle chicks from broods in the Highlands and raised and released them in an undisclosed location in the Moffat Hills.
Francesca Osowska, chief executive of NatureScot, which supports the project, said: “It is thrilling to see these four stunning golden eagles thrive in southern skies, in Scotland and England.
“These striking birds are helping enrich the wonderful nature in the south of the country.”