They once roamed the impenetrable forests and bleak mountains of ancient Ireland.
And there are those who would love to see wild wolves and brown bears roaming the Irish landscape once again – but could it ever happen?
For years, the idea has been mooted of repopulating wilderness areas of Britain with the top predators that once stalked the landscape. One report identified 23 species of mammals, birds, amphibians and fish that could return to Cairngorms National Park in Scotland, including large mammals such as wolves, Eurasian lynx and elk.
And this week, around 600 mammal experts gathered in Belfast to discuss the plight of mammals and whether those that have been driven to extinction in particular areas could be reintroduced to their former range.
It's not about nostalgia, according to Ian Montgomery, Professor of Animal Ecology at Queen's School of Biological Sciences, which is hosting the 11th International Mammalogical Congress.
In fact, there are sound ecological reasons for reintroducing lost animals to the places where they once thrived, particularly top predators such as wolves and large herbivores such as the red deer.
"The people who advocate reintroduction tend to advocate particularly important species – for example, predators which might be important to maintain species richness, or herbivores which might be important to maintain the richness of plant species," he said.
"What we're trying to do is restore a vital part of the ecosystem that has been lost and restore the impact which those top predators or herbivores had on the things on which they feed."
At the end of the last Ice Age, Professor Montgomery added, Ireland was a particularly barren place. As the climate warmed up, new species of mammals were able to move in, but temperatures dropped again and some of these species were killed off.
"Apart from that, 16,000 years ago Ireland became separated from the rest of Western Europe and relatively small numbers of mammals had managed to get into Ireland by that time, so the number of mammal species in Ireland was very small," he said
"There were probably wolves, probably red deer and probably stoat. But we were way out on our own in Europe and it was not a particularly nice environment.
"Humans probably brought in the lynx and a number of other things which have subsequently disappeared. It's possible that they brought in the wild boar, which died out at about 3,500 years ago."
But Professor Montgomery is very definite that reintroducing wolves to Ireland just wouldn't work. It could be ecologically sound to reintroduce wolves to Scotland, given the large areas of wilderness, but Ireland has too much domestic livestock and too many people living in scattered locations across the rural landscape.
"It would be inappropriate to bring that kind of wildlife and people into contact. It's not the kind of environment that we would want to bring wildlife back into."
Wolves are discreet creatures that are very unlikely to attack people, but they need a lot of space.
"The herbivores which we lost were lemmings and red deer and they're not going to survive in what is too warm a climate for them," Prof Montgomery added.
Wolves were a major part of Ireland's post-glacial fauna, and are prominent in ancient Irish myths and legends, in a number of place names, in archaeological sites and a considerable number of historical references. The ringforts, a common feature of the Irish landscape, were built partly as a defence against wolves and to protect livestock, over the period 1000 BC to AD 1000. The earliest radiocarbon date for Irish wolf remains come from excavated cave sites in Castlepook Cave, north of Doneraile, Co Cork, and date back to 34,000BC. The last wolf is said to have been killed in 1786.