American squirrel takes a foothold

RARELY has bird life in Ireland been receiving such publicity. Eagles, kites and hen harriers are all making headlines and attention could now be turning to the plight of songbirds which are facing a relatively new threat.

The American grey squirrel is having a devastating impact on Britain’s songbird population, according to a new study by the wildlife charity Songbird Survival. It now ranks alongside the cat as the top predator of farmland birds.

Looking deceptively cute and even cuddly, the same squirrel has established a firm foothold here since being introduced almost a century ago, and is now found in at least 23 counties.

But let’s digress for a moment and turn to an announcement by Minister of State Batt O’Keeffe of new measures to protect the hen harrier — a grants scheme for farmers who have been very much opposed to the designation of land for the promotion and conservation of this particular harrier.

Hen harriers are a medium-sized bird of prey with a small breeding population, 130-150 pairs.

“Farmers in hen harrier areas will be rewarded for the support that their labour provides for this beautiful, endangered species,” said Mr O’Keeffe, whose responsibilities include developing areas, when he addressed the Valuing Our Local Heritage and Culture conference in Newmarket, Co Cork.

“By maintaining open, well-grazed areas, farmers are giving the bird a hand in finding its prey. It’s a relationship that works very well, as hen harriers pick off unwelcome rodents that are no friend of the farmer.”

A standard rate of €350 per hectare in hen harrier target area lands will be paid through the National Parks and Wildlife Service scheme. The payments do not apply in commonage areas.

Hen harrier breeding habitat is found on low hills, especially in counties Kerry, Limerick, Cork, Clare and Galway. These birds require extensive areas of suitable habitat to forage over. They hunt small birds and mammals, foraging up to 5km from the nest over moorland, hill farmland and young conifer plantations. Harriers depend on open areas, particularly hill pastures, being farmed; without grazing, vegetation becomes too rank for them to hunt.

Special Protection Areas for the hen harrier include: Slieve Bloom Mountains, in Laois and Offaly; Stack’s to Mullaghareirk Mountains, West Limerick Hills and Mount Eagle, in Cork, Kerry and Limerick; Mullaghanish to Musheramore Mountains, Co Cork; and Slievefelim to Silvermines Mountains, in Limerick and Tipperary.

Back to the American squirrel, meanwhile. A survey is currently being carried out to ascertain how well distributed this bushy-tailed animal is around the country. Introduced to Longford, in 1911, it has been spreading out at a rate of about three kilometres per year which means it must be most counties at this stage. Fears have already been voiced about its impact on the native red squirrel, but now attention is also turning to its impact on songbirds.

In Britain, a study by Professor Roy Brown, University of London, involved assessing the effects of 10 common mammals on the populations of 15 farmland bird species, over 115 farms.

The study showed that, in areas of high squirrel density, 93% of small birds’ nests were predated. If the sparrowhawk is also a threat, this can lead to 100% breeding failure in some areas and a loss of 85% of adult birds.

“Many factors have been blamed for the decline in our songbirds in recent years, but mammal predation had largely been overlooked,” Prof Brown pointed out.

There have been calls for the eradication of the grey squirrel in Britain and, recently, the British Trust for Ornithology has been commissioned to investigate the effect of the grey squirrel on woodland bird population. According to experts, the American squirrel has no natural predators and has an insatiable appetite: if it comes across a chick or eggs, it gobbles them up.

In Ireland, Dr Michael Carey, of Combined Research and Inventory of Squirrels in Irish Silviculture is conducting a survey. He believes the grey squirrel is not only a threat to our native red variety, but is also responsible for widespread damage to broadleaf trees through the removal of tree bark. Meanwhile, recently released white-tailed eagles are now being sighted daily flying over the lakes and mountains of Killarney. Bird watchers from as far away as Fermanagh are coming to see them.