Management and Control of Populations of Foxes, Deer, Hares, and Mink in England and Wales, and the Impact of Hunting with Dogs

A Report to the Committee of Inquiry into Hunting with Dogs Management and Control of Populations of Foxes, Deer, Hares, and Mink in England and Wales, and the Impact of Hunting with Dogs Macdonald, D.W.1, Tattersall, F.H.1, Johnson, P.J.1, Carbone, C.1, Reynolds, J. C.2, Langbein, J.3, Rushton, S. P.4 and Shirley, M.D.F.4 1Wildlife Conservation Research Unit, Dept. of Zoology, South Parks Rd., Oxford, OX1 3PS; 2The Game Conservancy Trust, Fordingbridge, Hampshire, SP6 1EF; 3Wildlife Research Consultant, “Greenleas”, Chapel Cleeve, Minehead, Somerset TA24 6HY; 4Centre for Land Use and Water Resources Research, University of Newcastle upon Tyne, Porter Building, Newcastle upon Tyne NE1 7RU Management and Control of the Population of Foxes, Deer, Hares and Mink, Macdonald et al: and the Impact of Hunting with Dogs Executive Summary 1. Why seek to control populations of foxes, deer, hares, and mink in England and Wales? · A number of interest groups seek to control populations of foxes, deer, hares and mink for various, and often for several, reasons, summarised in Chapter 2. These reasons should be considered in the context of: ¨ An often ambivalent attitude to the species and its control. ¨ The general lack of a simple relationship between damage and abundance. ¨ Differences between perceived and actual damage sustained. · Foxes are widely controlled because they are perceived to kill livestock (lambs, poultry and piglets), game (including hares) and other ground-nesting birds. ¨ Fox predation on livestock is usually low level, but widespread and sometimes locally significant. Evidence is strong that fox predation has a significant impact on wild game populations, but less so for other ground-nesting birds. ¨ Fox culling by farmers is done, not in reaction to a current problem, but as a preventative measure, and out of fear of what might happen if the population increased. · Deer are routinely and widely controlled, in part because they cause damage by feeding on crops and young plantations, but also for amenity reasons, such as sport shooting and venison. ¨ Most studies to date of deer damage to agriculture in England and Wales suggest that this is rarely of economic significance at regional or national level. Where significant damage does occur, it tends to be localised and highly variable even between fields within a farm. ¨ Deer cause widespread and significant damage to forestry, but estimating the economic impact of damage is difficult, not least because trees (and cereals) may recover or even benefit from browsing · Hares are locally controlled because they are perceived to feed on crops and young trees, but there are few data with which to assess the damage caused. Following widespread declines, brown hares are subject to a Species Action Plan to increase their numbers, while mountain hares receive special protection under international law. · Mink are patchily controlled because of their predation on wildlife (particularly the water vole and nesting sea-birds), livestock (primarily poultry), and game. While there is ample evidence of their impact on wildlife, there are few data on their impacts elsewhere. 2. What methods are available to control populations of foxes, deer, hares, and mink in England and Wales? · At present, methods to control populations of foxes, deer, hares and mink in the UK all involve culling: shooting, hunting with dogs, trapping, and snaring. Chapter 3 summarises the methods used for each i Management and Control of the Population of Foxes, Deer, Hares and Mink, Macdonald et al: and the Impact of Hunting with Dogs species; only a few available methods are not used to any significant degree (e.g. snares for mink, live- capture traps for foxes, hunting with dogs for fallow and roe deer). ¨ For foxes, dogs, snares, rifles, and shotguns are combined in various ways to create a range of culling methods suited to different situations. The prevalence of these different methods varies substantially between regions in response to local conditions, land-use and traditions. ¨ For deer, hunting with dogs is confined to parts of Somerset and Devon; otherwise shooting with a rifle is the predominant method of population control. ¨ For hares, population control is usually achieved through organised driven shoots; hunting and coursing make no claim to act as control methods, although illegal, unplanned coursing may locally suppress hare numbers. ¨ For mink, trapping (with either killing or live-capture traps) is the predominant method; hunting with hounds is also widespread. · Methods available to control populations of foxes, mink, deer and hares are restricted by a number of statutes designed to satisfy the interests of individuals (game rights, crop, livestock and game protection), while also addressing general issues such as environmental and human safety, humaneness and conservation (Appendix 2). · Most operators use a combination of lethal techniques to control populations and non-lethal techniques to control damage. Physical exclusion by wire netting is widely used to protect vulnerable crops, livestock or reared game against deer, foxes and mink. More sophisticated approaches have either proved unpromising (conditioned taste aversion) or are still far from realisation (fertility control). · Assessing the extent to which different methods are used is made difficult by the disparate nature of available data. In particular, it can be difficult to clearly distinguish between control methods, as they might combine the use of several techniques, with the emphasis changing from place to place, day to day and person to person. ¨ For example, a single Welsh hunt might operate as a mounted hunt in lowland areas, a foot pack in open uplands, and as a gun pack in plantations, and in some or all of these situations might also use terriers, rifles or shotguns. ¨ Welsh packs, with their flexible modus operandi illustrate the difficulties in distinguishing clearly between methods that use dogs to kill, chase, locate or flush foxes (or indeed, other quarry). 3. What do simulation models suggest about the effectiveness of methods to control populations of foxes, deer, hares, and mink? · In Chapter 4 we use three modelling approaches to investigate the potential effectiveness of culling populations of fox, red deer, hare and mink. These are: population-level matrix modelling (all four species); individual-based modelling (for foxes and mink only); and Population Viability Analysis (PVA; for foxes only). · Population level matrix modelling simulated the impact of culling at a national level for all four target species. Individual-based modelling simulated the more detailed impacts of control strategies in simulated regions for which data were available to provide starting parameters. PVA examined long- term trends in regional fox population dynamics under different scenarios. · In population level models, hares were extremely resilient to culling mortality because of high productivity. For foxes and deer, a simulated cull causing moderate mortality in addition to existing mortality caused a long-term decline in model populations. ii Management and Control of the Population of Foxes, Deer, Hares and Mink, Macdonald et al: and the Impact of Hunting with Dogs · With individual-based modelling, simulated hunting with dogs (at levels of effort typical of the English Midlands for foxes) was ineffective at significantly reducing population sizes of either foxes or mink. For foxes, the simulated ‘culling at the earth’ and ‘shooting’ scenarios had significant impacts; in mink populations, both the ‘trapping’ and ‘trapping and hunting’ had significant effects on population size. · An important output of sensitivity analysis of the individual-based modelling was that predictions for foxes were very sensitive to input parameters representing dispersal, which is currently poorly understood. · PVA explorations showed that fox populations were resilient to changes in breeding and mortality rates, especially given adjacent populations with migration. Under the scenarios we explored, population isolation had more effect on population viability than moderate levels of culling (such as would result from foxhunting). The results however, did suggest that higher levels of culling could be used to hold fox populations at lower densities at which they were still viable. · Much more research is required on the basic mortality and dispersal biology of each of the species before we could use modelling in any tactical management of these species. The results of the modelling are therefore ‘general’. 4. How effective are methods to control populations of foxes, deer, hares and mink in England and Wales? · In Chapter 5, we distinguish two important aspects to the performance of wildlife management practices: effectiveness and efficiency. ‘Effectiveness’ expresses performance in terms of success in achieving the aims of management (e.g. reducing population size, reducing damage). ‘Efficiency’ expresses performance as the success achieved for a given cost (e.g. in time, in effort, or financial). ¨ An accurate measure of population size is an essential component of any measure of the effectiveness of population control (i.e. have the measures brought about the desired change in population size), or its efficiency (i.e. the cost of killing an animal known to be present). However, population size is notoriously difficult to estimate. ¨ Landholder’s perceptions of effectiveness and cost-efficiency may not be accurate. For example, farmers overestimate foxhunting bags by as much as 10-fold. ¨ Commonly used measures of effectiveness (e.g. numbers of animals culled) and efficiency (e.g. financial outlay required to kill one animal) can be very misleading because they do not take into account the density of the quarry. Nonetheless, these measures are components of any estimate of effectiveness and efficiency. · With the possible exception of red deer in the West Country, the data are not sufficient to calculate total numbers culled, or the proportion of the cull taken using each method; however, we do have relatively good data for organised methods of culling involving dogs (i.e. the various hunt Associations, and the National Coursing Club).

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