The reason the animals were introduced in the first place was pretty clear however. Some hunters fancied the opportunity to hunt the boar in the wild and released the animals illegally. One reported case in Co. Waterford saw a wild boar released into woodland in the Nire Valley, where a female boar was shot but not killed and left to roam injured in the woodland until some walkers found it and took it to the Deise Animal Sanctuary, a local animal shelter. The sad reality in that particular situation was that the animal was clearly a pet and whoever released it and tried to hunt it, did not have the know-how or the wit to do so properly, and is clearly not someone I believe most genuine hunters would care to be associated with.
In Britain, where wild boar were illegally introduced into the Forest of Dean, a genetic study by Frantz et al. (2012) revealed that the boar were hybrids between wild boar and domestic pigs. Due to the strict criterion of what exactly constitutes a native species based on IUCN guidelines, these animals did not qualify as a suitable population for restoration purposes, as they were not of pure wild boar genetic stock.
A similar by Allan McDevitt and co-authors, “Are wild boars roaming Ireland once more”, has just been published in the European Journal of Wildlife Research. McDevitt et al. obtained 15 samples of wild boar that had been shot by hunters and the National Parks and Wildlife Service in Ireland. Using reference samples from across Europe, McDevitt was able to characterise the genetic purity of the wild boar released in Ireland. What they found was rather surprising – the “wild boar” in Ireland were mostly derived from domestic pigs.
The study examined two types of molecular markers, both nuclear and mitochondrial DNA, to examine historical and contemporary integration from the putative wild boar and domestic pig populations, and conducted statistical analysis to investigate if the animals grouped more closely with pure wild boar or domestic pigs. Only three of the Irish wild boar retained any genetic similarity to pure wild boar, the majority were all domestic pig.
Two of the admixed (containing DNA from both species) samples constituted over 90% domestic pig, while the third sample was more like a true hybrid: half domestic pig and half wild boar. The other statistical analysis confirmed this grouping.
In the mitochondrial DNA (inherited through the female line), most of the pigs shared the same haplotype (DNA type) which was of Asian origin and that had been introduced into the domestic pig population across Europe, and is found in most European domestic pigs today. Two animals had a typical wild boar haplotype.
The results from the study clearly show that the wild boar in Ireland are genetically mostly domestic pig and do not constitute what we might call a true wild boar. The wild boar in Ireland contain less wild boar DNA than the animals found in the Forest of Dean, that officially didn’t even constitute a pure wild boar! The authors recommended that these findings should be factored into decisions regarding the future management of the species in Ireland.
Had the animals turned out to be pure wild boar, would the outcome really be any different? The animals were illegally introduced for hunting purposes, and not for the good of the ecosystem, our pool of native mammal species or any improvements the animals might make to our biodiversity and environment. I think the “nativeness” debate may have only condoned the illegal behaviour of those who introduced them in the first place. Ireland’s economy is still heavily dependent on the agricultural sector. Farmers have a lot of regulations to comply with in terms of the movement of livestock and regular testing of animals to help prevent wide scale disease outbreaks such as foot and mouth disease, which has previously shut down the agriculture industry for a long period of time. McDevitt et al.’s findings have shown that the Irish wild boar are essentially hairy domestic pigs roaming the countryside, with unknown disease status, unknown origin, and no mobility permit. We wouldn’t let an ordinary domestic pig roam around, why should an unkempt one be any different?
Frantz, A., Massei, G., & Burke, T. (2012). Genetic evidence for past hybridisation between domestic pigs and English wild boars Conservation Genetics, 13 (5), 1355-1364 DOI: 10.1007/s10592-012-0379-1
McDevitt, A., Carden, R., Coscia, I., & Frantz, A. (2013). Are wild boars roaming Ireland once more? European Journal of Wildlife Research DOI: 10.1007/s10344-013-0721-z
