Why did the Killarney National Park fire cause so much damage?

Evidence suggests management of landscape needs to be independently examined

There has been much speculation about the immediate cause of the massive fire in Killarney National Park in late April. A Garda investigation is under way.

But it is surely equally important to establish why this fire became so intense and spread so quickly, sometimes right into the heart of the oakwoods that are the park’s crown jewels. Experts tell us that these woods should be very hard to burn right through.

The last big fire, in 1984, generally failed to penetrate the oakwoods. The recent blaze appears to have done so repeatedly, with devastating consequences for plants and wildlife.

What caused this contrast?


If the dead rhododendron is a major factor in the fire's penetration of the oakwoods, this was a disaster long foretold

Studies after the 1984 fire established two points: the Killarney woods are damp, temperate rainforests. Heathland fires will damage peripheral trees, but cannot reach into ecologically sound oakwoods, because their typical native vegetation does not conduct fire well, and oak trunks are fire resistant.

Ironically, oakwoods infested by live rhododendron, though in poor ecological condition, will also repel fire. Rhododendron’s thick evergreen foliage does not easily burn. So this invasive alien shrub, which prevents oak regeneration and ultimately destroys whole forests, can protect them in the present.

A local environmental group, the Killarney Nature Conservation Group (KNCG), has recently published a post-fire analysis, backed by photographic evidence, which highlights a significant difference in woodland condition today. It shows that extensive dead rhododendron thickets have accumulated around and within the woods. These thickets, according to the group, have become the fuel that can link heathland fires and the forest interiors.

The KNCG analysis attributes this fuel accumulation to the current rhododendron eradication strategy in Killarney. The National Parks and Wildlife Service (NPWS), which manages the park, has since 2005 been killing rhododendron by stem injection with herbicide. This is quite effective, but the NPWS’s own rhododendron manual warns repeatedly of the fire hazard posed by leaving dead rhododendron standing within oakwoods.

The KNCG analysis links to hundreds of geotagged photographs which show extensive charred rhododendron remains alongside badly burnt oaks in some Killarney woodland interiors. Photographs from previous years show dense thickets of dead rhododendron inside these woods. The group’s analysis is endorsed by Friends of the Irish Environment, and by individual conservationists with long and deep experience of the park.

If the dead rhododendron is a major factor in the fire’s penetration of the oakwoods, this was a disaster long foretold. KNCG quotes a letter from Bill Quirke to the National Parks and Wildlife Service in 2012, warning that the oakwoods were “now at significant risk of being partially or largely destroyed” because of the growing volume of deadwood.

We can derive some hope from the very welcome independent review of the entire NPWS currently being undertaken at the behest of Noonan. The future health of our landscapes and biodiversity could hang on the outcome

Quirke knows his stuff: he had been contracted full time as an ecologist by the park through the 1980s, had pioneered the successful rhododendron clearance by Groundwork volunteers up to 2005, and had edited a 2001 book on the park endorsed NPWS.

The NPWS told Quirke that “these [deadwood] issues are known to us” and promised that his observations would “contribute . . . to our decision-making processes”.

Removing so much deadwood is undoubtedly labour intensive and, if badly done, could cause erosion. But it is arguable that the oakwoods would have been better protected from fire had the eradication programme proceeded on the basis of only stem-injecting thickets when resources were available to remove their remains.

One might imagine that the NPWS would welcome the KNCG’s voluntary contribution to elucidating the causes of this fire’s exceptional impacts, accompanied by so much geotagged photographic evidence. True, the KNCG analysis is not definitive – the group itself rightly describes it as “preliminary” – but it surely raises questions that need answers. After all, we are encouraged, sometimes by the NPWS itself, to become citizen scientists these days, to help combat biodiversity loss.

So the response from Minister of State Malcolm Noonan’s Department of Housing, Local Government and Heritage is troubling: “Investigations of this type are highly specialised and this kind of speculation by parties unknown and unqualified in investigative work of this nature is in fact dangerous, misleading and an unhelpful distraction.”

In fact, the KNCG statement is signed by Mike O’Sullivan, a professional incidents and accidents investigator who knows the park well. Other contributors to the analysis have strong ecological credentials and decades of experience of the oakwoods.

But credentials may be beside the point here: determining whether or not the dead rhododendron contributed to the fire’s spread and intensity is hardly rocket science. What is really troubling about the department’s statement is that it does not focus on this core question, though it has been quoted as simply denying it was a factor, without explaining its rationale.

The catastrophe in the park had several causes. The broad context is global heating, and the specific trigger may have been fires set by rogue grazers and/or by visitors with barbecues. That’s for the Garda and the fire service to determine. But the KNCG evidence suggests that the management of this landscape also needs to be independently examined to prevent such intense fires in the future.

We can derive some hope from the very welcome independent review of the entire NPWS currently being undertaken at the behest of Noonan. The future health of our landscapes and biodiversity could hang on the outcome.

Paddy Woodworth is a writer and Research Associate at Missouri Botanical Garden, St Louis

The KNCG report, with links to photos, is at drive.google.com