The Irish hare Lepus timidus hibernicus is the only species of lagomorph native to the island of Ireland. Carbon dating of cave fossils has shown that hares were present in Ireland as far back as 30,000 BP (years before present). This species is now thought to have continuously inhabited Ireland since before the last ice age.
The Irish hare’s unique morphology, ecology and behaviour as compared to other mountain hares seem to be the result of genetic adaption over a period of at least 30,000 to 60,000 years. Consequently the Irish hare possesses a high number of unique genetic characters that are not shared by any other hare species outside of Ireland. This suggests the current Irish hare population could be the only remaining descendants of an older genetic lineage that was probably common in Europe prior to the last Ice age. So although the Irish hare is currently classified as a sub-species of the mountain hare there is now compelling evidence that it should be given species status in its own right.
The Irish hare is about the same size as the mountain hare (Lepus timidus scoticus). Coat (pelage) colour varies, even within the same group, from russet brown to light brown or blond. There are two moults and the coat can vary throughout the year, developing white patches. Its fur does not normally change to white in winter although it can become lighter and greyer. Colour change in Irish hares is more prevalent in very severe winters. Few Irish hares turn completely white but all white specimens have been reported and some have gained a place in folklore.
Irish hares and brown hares (Lepus Europeaus) may be difficult to distinguish in the field due to the variations in pelage and tail colour. As with the mountain hare, the black tipped ears of the Irish hare are shorter than those of the brown hare The upper surface of the brown hare’s tail is always dark, while the Irish hare’s tail may be white or dark in colour.
Irish hares can be found from hill-top to sea-shore and there are reports of them grazing on sea-weed. However, they are most likely to be found in “unimproved” areas of species rich vegetation and tall plants such as rushes. This provides not only food but also cover and shelter where they can lie up during the day, out of sight of predators.
Irish hares appear to be relatively solitary animals for most of the year with a limited range and dispersal. Studies have produced figures of between 10 and 40 hectares as the Irish hare’s typical range. Although not highly social, Irish hares exist as local populations, some of which have now become extinct.
Irish hares breed throughout most of the year, with leverets recorded from January through to November. With a gestation period of 52 days and a lactation of around 6 weeks, this means that females (does or jills) may be in an active breeding phase at any time. Irish hares are thought to have up to four litters a year of between one and four leverets, the average being two. 75% of the leverets are unlikely to survive their first year of life. Like the brown hare, Irish hares do not breed in their first year.
Irish hares have been in serious decline since the early 1900’s owing to changed farming practices, especially mechanised grass cutting. Their persecution for sport may also have had a major impact. The Ulster Wildlife Trust has warned that hare hunting and coursing “may prove to be the final straw for some of the more isolated populations.” In an article on 23 May 2005, the Irish Independent placed the Irish hare alongside the corncrake and the marsh fritillary butterfly as species under severe threat in Ireland.
Organised hare coursing has now been banned in Northern Ireland but remains widespread in the Irish Republic. Throughout Ireland, the Irish hare remains a quarry species and may be hunted with guns or dogs despite evidence of on-going long term decline. The most robust time series survey data available suggests that hare numbers have declined in Northern Ireland by around 50% over a six year period between 2004 and 2010.
Historically large colonies, such as those at Aldergrove near Belfast and Bull Island near Dublin have also declined. Rathlin Island, off the North Coast of Ulster, remains a stronghold for Irish hares. It is home to the Rathlin ‘golden hare’, which displays a distinct genetic variation producing individuals with blue eyes.
Brown hares were introduced to Ireland by landowners in the 19th century. These appear to have died out although a small population exits in North West Ulster. It is not know if these individuals are descendants of the original imported hares or the result of a more recent introduction. Irish hares and brown hares may interbreed but the degree of threat to the future of the native Irish hare population is unknown.
Irish hares were also introduced to Mull from Ireland, although it’s not clear when this took place. DNA taken from hares on Mull has verified their heritage.