Cork's barn owl population takes flight

A county-wide study has revealed that Cork has seen a remarkable resurgence in its barn owl population in recent years, helped by the conservation efforts of Bird Watch Ireland volunteers.

Speaking to the Cork Independent, BWI Barn Owl Research Officer Dr Alan McCarthy said that just a decade ago, barn owl numbers in Cork were relatively low. “5 years ago we would have known of 20 to 30 nests in Cork, but there definitely has been an increase in recent years,” he said.

“This year we wanted to do a full county survey to get an updated picture of how the species was faring. We had noticed from the research we had been doing that there had been an increase, and this year so far we have found 100 nest sites in the county,” he added.

This growth can be attributed to a combination of factors, foremost among them being the changing landscape of small mammal populations in Cork. “Barn owls mostly feed on small mammals; rats, mice and shrews,” he said.

“In recent years there has been a new small mammal spreading throughout Cork, called the greater white-toothed shrew. They were first discovered in Tipperary in 2007, and the shrew population has been growing throughout the country since at a rapid rate. We find them in North Cork and East Cork and they are starting to spread into West Cork. Where they are established, an increase in barn owl numbers tends to follow,” he said.

The decline of barn owls between the 1970s and 2000s was due to factors such as rat poison, road casualties, and habitat loss due to agricultural intensification, explained Alan. While the current barn owl resurgence is nationwide, it's particularly notable in Munster and South Leinster.

Alan said that volunteer efforts have played a crucial role in bolstering barn owl numbers. Around 40 of the 100 nest sites identified this year in Cork were in nest boxes installed by local volunteers. These nest boxes have proven to be pivotal in providing safe havens for barn owls to breed and thrive.

Barn owls are not the only species experiencing population growth in Cork. After being driven to extinction, buzzards have successfully reestablished themselves in Cork over the past two decades. “In the early 2000s they began breeding in Cork for the first time in over 100 years. They are good news for farmers because their main prey is rooks, rabbits, rats and wood pigeons. Buzzards do a great job at reducing them,” said Alan. For those interested in creating a nestbox for barn owls, information can be found on Bird Watch Ireland’s YouTube channel where there is an instructional video available to view.

Dr Alan McCarthy will be giving a talk on the findings of the survey on 18 October at 8pm in the SMA Hall in Wilton. The Barn Owl Survey is funded by Cork County Council, supported by the National Parks and Wildlife Service through the Local Biodiversity Action Plan Fund and the report will be published by the end of the year.