Reintroducing the boar: a wild notion?
An argument about the status of Ireland’s wild boar raises key issues for conservationists, writes PADDY WOODWORTH
WHEN CAN WE consider an animal to be native to Ireland? And if a native animal has become extinct here, is it always good to reintroduce it to our landscapes? These awkward questions arise after a disagreement between the Irish Wildlife Trust and Invasive Species Ireland about the status of the wild boar became public this week.
The wild boar is a formidable and hairy beast that makes the farmyard pig look like a weakling. It has been making unscheduled appearances in our countryside with increasing frequency. A 180kg male was shot near a school in Co Tipperary, and there are also recent records of boar breeding wild in Co Wicklow and Co Kilkenny, plus sightings in other counties.
Many of these animals probably escaped from farms – wild boar is a staple item on menus in continental Europe. There is some suspicion, though there is no proof, that some may have been released deliberately, by hunters seeking to promote an exotic prey species, by people with an interest in “rewilding” the Irish landscape, or by both.
Rewilding is a radical conservation strategy, originating in the US, based on the idea that healthy ecosystems need their full suite of species, including top predators, such as wolves, and top herbivores, such as elephants. There is a sound scientific basis for this as a theory: take wolves out of the equation and, unless other forms of control are used, deer populations will explode, with dire effects on vegetation and on other animal species.
Though the evidence is conflicting, the reintroduction of wolves to Yellowstone National Park appears to have boosted the park’s ecological health.
In other contexts, however, translating the theory into practice is obviously problematic – and sometimes simply daft. The goal of the “Pleistocene rewilders”, who want to translocate African elephants to the Great Plains of the US, to replace mastodons that have been extinct for thousands of years, should surely be put on a very long finger.
Humans have by now removed so many native species from landscapes, introduced so many aliens and made so many other changes to ecosystems that very complex biological cost-benefit analyses need to be made before reintroductions take place. Even then there may be unforeseen outcomes.
What has all this to do with Ireland’s errant wild boars? Well, last November Invasive Species Ireland announced an action plan to prevent the establishment of wild boar on the island of Ireland. The group is a joint initiative of the National Parks and Wildlife Service and the Northern Ireland Environment Agency, dedicated to protecting our island from the scourge of ecologically destructive alien species.
Invasive aliens outcompete native species because the predators or diseases that would control them in their original environments do not exist here. Rhododendron, grey squirrel and zebra mussel are familiar and noxious – in an Irish context – examples.
But last Wednesday the Irish Wildlife Trust put out a statement objecting to the group’s classification of the wild boar as “invasive”. While recognising the potential problems that the group had identified – especially that of diseases that might spread from boars to farm animals – the trust goes on to suggest that a carefully planned reintroduction of the animal should at least be considered.
Two arguments need to be disentangled here. The first is whether the boar really is an alien or whether it is an extinct native. The second is whether it is always good to reintroduce native species that have become extinct.
Invasive Species Ireland says wild boars became extinct in Ireland 5,000 years ago. The trust places it here much more recently, though vaguely, “in historical times”. The hard evidence is, as often in such cases, ambiguous. Either way, however, it does seem that the boar can claim extinct-native status.
But that does not mean it might not become invasive, in the sense of displacing other native animals and plants, if it were reintroduced today.
Given the problems posed to foresters, farmers and native biodiversity by overgrazing deer, the reintroduction of the wild boar would appear to be, at the very least, premature.
Reintroductions of charismatic species have a strong appeal, and sometimes they work very well, though not without great difficulty and cost.
The excellent work of the Golden Eagle Trust, in partnership with the National Parks and Wildlife Service, in bringing back eagles and kites to our skies is a well-known example.
But each case must be considered on its merits, especially given the scarce resources available for conservation today. Some years ago the Irish Wildlife Trust advocated the reintroduction of the great spotted woodpecker. The project never gained traction, but over the past five years woodpeckers have recolonised Ireland of their own accord, adding diversity and colour to our landscape, at no cost whatsoever. “Hasten slowly” would seem to be a good motto for reintroduction projects.
Paddy Woodworth’s Restoring the Future, a survey of ecological restoration projects worldwide, will be published by University of Chicago Press later this year