ReWild Wicklow is calling for the implementation of a deer management plan following its observation of the non-native Sika species dominating local deer populations.

The conservation group set up 47 cameras across 220 sq/km of forest land in the county to observe wildlife behaviour over two months last year.

Of the 6,300 wild mammal events captured by the cameras, 72% were of Sika deer.

On The Pat Kenny Show this week, ecologist Adam Smith, who was involved in the study, said deer are “an integral part of our woodlands.”

“They help facilitate a lot of structural diversity, even sometimes stimulating regeneration and maintaining open areas,” he said.

“But certainly, at high densities, they can cause a little bit of damage, of course - grazing, over-browsing, bark stripping from trees and preventing the regeneration of woodlands too.

“As you can imagine, this might impact biodiversity down the line - things that rely on the regeneration of trees or ground flora, such as birds or invertebrates.”

Benefits

Mr Smith, a PhD student from Kildare, said deer bring many benefits to woodland areas.

“If you imagine over the course of a deer’s lifetime, it’s grazing and browsing certain trees and it’s moving nutrients around the landscape as it defecates,” he said.

“When a deer dies of natural causes, or is killed by a disease or something, it provides a huge boom of nutrients to scavengers and insects.

“There are many positive effects of deer - it’s just when the balance is out of whack that we might need to come in and say, ‘Okay, let’s see if we can manage this back to something sustainable.’”

Non-native species

Mr Smith said there are also “ecological arguments” for why we should not have non-native species of deer in Ireland.

“There are cultural arguments for why they are important as well,” he said.

“It’s not something that I can just come out and say, ‘Yeah, we’re going to eliminate a whole species off the island,’ probably because it’s also not feasible - but certainly, we can rebalance things a bit.

“If you look at our results, we have a huge prevalence of Sika, but we don’t really have Irish red deer in Wicklow.

“We have some hybridisation, which is between Sika and red deer, but there is no red deer in the same way there would be in Killarney, for example.”

There are currently four deer species in the wild in Ireland, including Fallow Deer and Reeve’s Muntjac, in addition to the previously mentioned Red Deer and Sika Deer.

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