Hopes for local revival in barn owls to take flight

Barn owl populations appear to be making a bit of a comeback in County Cavan, according to local bird experts.

Widespread decline has seen majestic bird red-listed, which means it is designated as being ‘of conservation concern’.

It is thought intensification of agriculture, land use changes, an increased use of anti-coagulent rodenticides and the expansion of road networks, have factored into the fallback over the decades.

However, barn owls now appear to be enjoying an upswing in fortunes with increased sightings across the country as they move into custom-built nest boxes and suitable undisturbed old ruins.

The medium-sized bird with its distinctive rounded heart-shaped face and deep black eyes has its stronghold in the south west of the country.

Birdwatch Ireland suggest this could be down to the presence of the greater white-toothed shrew and the bank vole, two invasive species favoured as prey. These mammals are most common found in Munster, Leinster and Connacht, but have noticably migrated further north over the years.

So where does that leave Cavan’s Barn Owl population?

Bird Watch Ireland, in conjunction with Cavan County Council, recently undertook a summer survey and research officer Alan McCarthy shared the findings at a packed meeting of the local branch in Cavan Town last Wednesday evening.

Study

Alan explained that of 51 potential sites surveyed throughout Cavan, 38 were deemed “suitable or potentially suitable” as nesting sites for barn owls.

“Of these 38 sites, in total we found six nest sites,” said Alan acknowledging the heavy survey leg work was carried out by Isobel Oakes.

Compared to the late 1960s this represents a 55% decline in breeding range. However, more positively, compared to the 1980s there has been a modest rise.

Just 15 years ago there were no confirmed barn owl nest sites in the county. Combined with trends elsewhere Alan suggests Cavan survey results signify a cause for quiet optimism.

County Monaghan is experiencing a similar breeding boon, although a Birdwatch survey this year identified just one confirmed nesting site.

Cavan and Monaghan are the only counties in Ireland where the invasive field vole has now been identified, another likely species for the barn owl to feed upon.

Cork has had bank voles since the 1980s, and the invasive shrew in more recent years, so it is further along the national trend of decline in barn owls and noticable upturn since. Last year they found 114 nests in County Cork.

Extrapolating these trends to Cavan, Alan surmises: “I wouldn’t be too surprised if in five to 10 years we have up to 30 nests potentially.”

The lack of suitable nest sites though could place a greater emphasis on the importance of providing more nesting boxes.

One place surveyed this summer where a nest box yielded great results was on the O’Reilly farm in Kilcogy. There was great excitement as Alan weighed, measured and ringed four barn owl chicks.

Hopes

The nesting boxes have been occupied by owls there for the past three years, but this is the first time they have produced chicks.

“They took them out, they weighed them, they measured their wings and they put a ring on the leg of each chick. They’re the first barn owl chicks ever to be rung in Cavan,” Paul O’Reilly was happily reported to the meeting.

The Kilcogy man explained how the ring will show where the birds originally came from if they relocate in adulthood, as they typically do.

“It’s for research and data purposes,” he added.

Paul and fellow bird enthusiast Brendan Smith put the boxes up on Paul’s brother’s farm 24 years ago. Both men, along with Paul’s son Emmett are “fascinated” by the species.

“We said we’d put up boxes just on the off chance they might use them,” he said, adding that other bird species have used them over the years.

“This is the first time we’ve had successful Barn Owl chicks in 20-odd years.”

Upon first sight of the owls, Paul asked neighbouring farmers not to put down rodenticides.

“Obviously if the owl picks up the rat or mouse that’s after eating the poison he’ll die as well,” he explains.

They hope the Barn Owl family will continue to expand, and Paul notes that his son Emmett shares his passion for the bird.

“Like the rest of us he was overjoyed,” Paul said of Emmett.

Birdwatching has been Tom Broe’s passion since childhood. The Crosskeys man is a member of the Cavan branch of BirdWatch Ireland.

“They are top of the food chain, so if they’re doing well it’s a sign of a healthy ecosystem,” explained Tom of barn owls’ importance to Cavan.

Tom has never sighted the bird in Cavan and said members of the public may have difficulty in doing so.

“They’re nocturnal and they’re not always that vocal, it’s quite possible you could have a pair nesting quite close to you and you wouldn’t be aware of it.”

Evidence of the species could be pellets, signs of excrement or white spray and feathers.

“Again that could equally be other species,” he said.

Tom hopes the survey will act as a “baseline” that will be repeated in maybe five years time to see if numbers do increase.