Elusive hen harriers start breeding on Lewis amid improved conditions

HEN harriers have established a breeding population on Scotland’s largest island for the first time in recorded history.

One of Scotland’s rarest birds of prey, the hen harrier population has suffered from illegal persecution for many decades.

A study in 2016 found there were only 460 territorial hen harrier pairs in Scotland, representing a decline of 9 per cent since 2010, although it is estimated there is the capacity to support more than 1,500 pairs.

Robin Reid, RSPB Scotland’s conservation officer for the Western Isles, said the “now precarious and declining status of harriers across

Scotland makes their recent appearance on Lewis even more important”.

It also extends the elegant birds’ breeding range to the north-west of Scotland.

Mr Reid said: “The first nest on Lewis was located in 2015 and in 2016 four nests were found.

“Surveys in 2019 located nine pairs and it is now estimated that there are over 10 pairs breeding on Lewis.

“Harriers can be elusive and, although it is possible that isolated breeding attempts went unnoticed before 2015, the species was not a regular breeder and harrier sightings were rare.

“The neighbouring islands of Uists have a healthy population of hen harriers and it had been thought that their absence from Lewis was due to a lack of voles, one of the hen harriers main prey species.

“However, it is now thought that hen harriers have established on Lewis in response to changes in land management.”

Mr Reid said that sheep numbers had decreased on Lewis over the last 20 years and as grazing pressure had dropped, heather had recovered, providing nesting habitat for harriers and more habitat for prey species such as meadow pipits.

The presence of some young plantations in moorland areas is also likely to have been attractive to harriers, he said.

He added: “We think these changes have enabled hen harriers to colonise, but more research is needed as we don’t yet know much about what this population is feeding on in the absence of voles.”

Mr Reid warned, however, that the core area where the harriers have chosen to breed was also the site of the proposed Stornoway Wind Farm, a large 35 turbine proposal which is currently at application stage.

He said: “The RSPB has responded to this planning proposal with concerns that the wind farm poses a threat to the harriers both from collisions with turbines and disturbance from the construction and operation of this large development.

“We have asked for the removal of a number of turbines which are closest to the breeding and roosting sites of hen harriers and other sensitive species.

“This would mean that the renewable energy project could potentially go ahead while reducing the impacts on this new and fragile hen harrier population.”