Hen harrier shows signs of a comeback
HEN HARRIERS are one of the country’s threatened birds of prey, and among the leastknown aspects of their ecology, where they go once they leave the breeding grounds, how many survive their first year and where and when they return to nest.
All of those answers have now been answered thanks to a programme of satellite tagging which was initiated two years ago by the National Parks and Wildlife Services and the EU-funded RaptorLife project at IRD Duhallow.
Birds have been tagged across north Cork as well as in Waterford, Laois and Offaly.
Dr Allan Mee, Project Scientist of RaptorLIfe at IRD Duhallow, said a female hatched at a nest in the Mullaghareirks north of Ballydesmond and, in 2017, returned to breed at a site in east Kerry.
He said, “We were excited to see where this female would spend the summer, but we weren’t expecting her to nest this year. Although Harriers typically return to breed in late-March and early-April, this female did not leave her wintering grounds on the Wexford coast until well into April, arriving at her breeding site on April 29.”
Dr Mee said within two weeks, however, she had not only found a mate but had laid four or five eggs.
“By late-June the pair were feeding their young typical prey items such as small birds like Meadow pipit. The unusually hot and dry weather posed a real problem for the nesting pair. Birds of prey get all their water needs from their prey so, dehydration and overheating was a real life and death issue for the chicks.”
But despite this, the nest progressed well until the chick was three to four weeks old.
With just days to go until the young would themselves take their first flight, the nest was spotted by a fox – which is an indication of the pressures that birds such as Harriers face in the race to raise chicks in the wild.
“Within a day of losing her brood, the satellite-tagged female had travelled some 110 kilometres east to Slievenamon in south Tipperary,” he said.
“Although the loss of her brood was disappointing to the RaptorLife project, the team were delighted to see this female return to breed in her first year.”
Dr Mee pointed out that major threats to Hen Harriers are large-scale afforestation, increased industrial-scale wind-farms in the uplands, and human disturbance and land use such as turf cutting.
He also said that while Hen Harriers readily take to young conifer plantations to nest, conifer forests can only be used for a few years before the forest canopy closes over at 10 to 12 years.
“Therefore, large parts of the uplands become unusable to harriers between 10 and 40 years before the crop is harvested and replanted,” he said.
Dr Mee also said that over the last five years of its lifetime the RaptorLife project has been working with the farming community in Duhallow to deliver benefits to Hen Harriers and the wider ecosystem along the upper Blackwater catchment.
“It is hoped that working in tandem with farmers on the ground that both farming and wildlife will have a positive future in the Duhallow region.”