Techniques for assessing the abundance of brown hares Lepus europaeus

摘要: Over the last few decades, there have been significant declines in Brown Hare Lepus europaeus numbers throughout Europe, leading to concern for their status many countries. In Britain, were no quantified data on extent of this decline, current population levels, or any baseline against which monitor future changes. The need a national hare survey led evaluation techniques available assess numbers. Published information counting hares is reviewed, and various compared by applying them number sites southern England. Three basic approaches are available: counts inactive hares, active indirect methods. Counts include total clearance, wide belt line transect counts. Total clearance give an absolute figure, but labour intensive can only be applied restricted areas. Wide-belt assessments difficult apply certain habitats even open areas tend produce substantial over-estimate. Line easy undertake not should large areas, from several small combined. based more problematical, because it determine what proportion at one time. Spotlight variable circular plots most accurate widely, twilight very subjective interpretation, especially when surveying with concealing habitats. Of methods, dung pellet valuable specific across range habitats. We concluded that, considered, greatest potential survey, stratified so that enough transects undertaken within each habitat stratum obtain reliable mean estimate stratum.