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Northern Ireland Irish hare Survey 2008

The Irish hare (Lepus timidus hibernicus Bell, 1837) is the only native lagomorph in Ireland and is currently classified as an endemic sub-species of the mountain hare (L. timidus Linnaeus, 1758). It attracted major conservation concern following a population decline during the late 20^th century. It currently has two Species Action Plans one for Northern Ireland and another covering All-Ireland. It is one of the highest priority species for conservation action in Northern Ireland.

The survey was undertaken during spring 2008 and compared to previous surveys undertaken from 2002 to 2007. Standardised field survey methods and analytical techniques were employed to enable direct between-year comparisons enabling relative change in hare density to be evaluated.

Using conventional analysis the mean estimated Irish hare density in Northern Ireland during early 2008 was 2.86 hares.km^-2 (95%CI 2.16-3.79), giving a total estimated abundance of 40,500 hares (95%CI 30,600-53,700).

Estimated hare density during 2008 was lower than during 2007 but the 95% confidence intervals of both estimates overlapped substantially. Therefore, there has been no significant change in the hare population since 2007.

We make 3 recommendations:

1.       Regular surveys of Irish hare abundance are necessary to establish the extent and pattern of annual fluctuation. Annual deployment of standardised survey methods will enable continued evaluation of relative temporal change in hare abundance.

2.       If accurate estimates of absolute abundance are required, a retrospective re-analysis of hare survey data using custom Distance analysis techniques will be needed. Improvements in Distance analysis methods made by Quercus in collaboration with the Research Unit for Wildlife Population Assessment (RUWPA) in the University of St. Andrews, may enable past, current and future estimates to be refined increasing their accuracy and precision. This may be incorporated into an assessment Irish hare Species Action Plan targets during 2010.

3.       Research on the population biology of Irish hares remains necessary. There is insufficient information on the most basic aspects of demography such as survival and productivity. Particular attention should be given to the influence of pastoral farmland management (e.g. silage harvest) on population recruitment.