Download The impact of a ban on snaring on Scottish agriculture

OneKind Report on Snaring
Chapter 4
The impact of a ban on snaring on Scottish agriculture
Authors: Professor Stephen Harris and Dr Steve Ross
School of Biological Sciences, University of Bristol
Woodland Road, Bristol BS8 1UG
December 2010
Chapter 4
CONTENTS
Executive summary and conclusions
Introduction
Scottish agriculture
Agricultural losses
Agricultural losses to foxes
Agricultural losses to mink
Agricultural losses to rabbits
Agricultural losses to brown hares
Agricultural losses to mountain hares
The wider economic perspective
Snaring to protect agriculture in Scotland
General points
Snaring foxes
Snaring mink
Snaring rabbits
Snaring brown hares
Snaring mountain hares
Effects on population sizes
Inter-species effects of culling
Discussion
References
Executive summary and conclusions
The snaring of wildlife is an emotive issue. In this chapter, we review the potential impact of
a ban on snaring on Scottish agriculture; we include all forms of agriculture, forestry and
freshwater aquaculture. In particular, we consider how widely snaring is used in Scotland to
reduce agricultural losses to foxes, mink, rabbits, brown hares and mountain hares, the
economic impact of these species, how widely snares are used to address problems that
arise, and the impacts of culling programmes on both population size and numbers of other
species.
We show that:
There has been no change in fox numbers in the UK over the last 30 years, and
densities in Scotland are low.

Structured surveys of farmers throughout Britain show that agricultural losses to
foxes (lambs, free-range poultry and piglets) in Britain amounted to just £12 million
in 2000.

The losses were offset by the benefits of fox predation on rabbits and rodents, and
that at worst foxes were economically neutral to farmers. One study put a significant
positive value on the benefits of fox predation to farmers.

There was no evidence that foxes were reservoirs of parasites of importance to
farmers.

Agricultural losses to mink in the 1980s were low, and there have been significant
declines in mink numbers in Scotland since the 1990s.

Economic losses to rabbits are significant; the latest estimate put this at £12 million
to Scotland in 1990/1991. Rabbit numbers have undergone a significant decline since
the mid-1990s.

Agricultural losses to brown hares at current densities are minimal.

Agricultural losses to mountain hares, mainly browsing on young trees, are low.

The economic losses to these species are minimal both in terms of losses to each
sector, the overall contribution of agriculture to the Scottish economy, and the
overall levels of food waste.

Claims that snaring foxes is essential to reduce losses of lambs do not stand scrutiny:
snaring does not appear to be widely used by farmers to address problems that
arise.

Trapping is the most effective way to catch mink and snaring does not appear to be
used by farmers.

Snaring is not recommended by professional advisors as a means to reduce
economic losses to rabbits.

Snaring is not widely used to catch brown hares, and is not considered effective or
acceptable to farmers or other practitioners.

Snaring is not widely used to reduce forestry/agricultural losses to mountain hares;
licences were issued by the Scottish government to catch just 0.2% of the mountain
hare population in 2006/2007.

There are complex interactions between these various species, and reducing
numbers of one species can lead to significant economic impacts from other species
of wildlife.

There is no evidence that a ban on snaring will significantly impact on Scottish
agriculture.

The arguments in favour of the retention of snaring are the same as those used in
favour of continuing to use gin traps to catch rabbits and foxes. The ban on the use
of gin traps in Scotland in 1974 had no obvious adverse effects on Scottish
agriculture.

Cost:benefit analyses suggest that, as a general rule, resources should be better
focussed to reduce agricultural losses to wildlife, and that a lot of the money spent
on culling wildlife should be redirected to long-term measures to reduce impacts.
Introduction
It is widely argued that snaring is vital for food production in Scotland. For instance, the
Scottish Government has publicly stated that it agrees with the statements made by
Jonathan Hall, Head of Rural Policy at the National Farmers Union Scotland, who stated that
"The hill farming view on snaring is that it remains an absolutely vital tool in protecting
livestock, particularly lambs around lambing time, from fox predation" and that "The loss of
snaring would have extremely adverse consequences for hill farming in particular"
(Cunningham 2010). Similarly, in a joint document, the British Association for Shooting and
Conservation, the National Farmers Union Scotland, the Scottish Countryside Alliance, the
Scottish Estates Business Group, the Scottish Gamekeepers Association and the Scottish
Rural Property and Business Association stated that, as a reason to support snaring for
agriculture, fox control is vital, especially to protect lambs in hill farming areas, and that it is
increasingly done in partnership with local gamekeepers. They also state that rabbits must
be controlled to protect agricultural crops as well as sensitive flora and that snaring is one of
the most widely used methods of rabbit control (Anon. undated a). Similarly, the leaflet
Snaring in Scotland: a practitioner's guide states that "fox and rabbit control in Scotland is
necessary to ensure that damage to crops, livestock, trees, game and other wildlife and
their habitats can be reduced to acceptable levels. Snaring is a vital tool to achieve these
ends in Scotland due to diverse landscapes and types of cover" (Anon. 2008).
Many such statements roll the case for snaring to protect agriculture and game interests
together, making it difficult if not impossible to assess the importance of snaring to
agriculture in Scotland. The sources do not include quantified data on the need to use
snares to protect agricultural output, least of all cost:benefit analyses. Whilst the main focus
in Scotland and the rest of the UK is on snaring foxes and rabbits (e.g. DEFRA 2005a), both
mountain and brown hares are snared, and snares may also be used to capture species such
as mink and grey squirrels (DEFRA 2005b). There is little evidence of snares being used to kill
grey squirrels in Scotland, but we will consider the other five species when reviewing the
need to use snares to protect Scottish agriculture. Whilst we focus on data from Scotland,
we use information from the rest of the UK (and occasionally elsewhere) where appropriate
to provide a quantified assessment of the importance of snaring to Scottish agriculture, the
potential economic losses of foxes, mink, rabbits, brown and mountain hares, and the
economic and other consequences to Scottish agriculture of a ban on using snares.
Scottish agriculture
To understand the potential impacts of a ban on snaring, we need to consider the current
and future patterns of agriculture in Scotland. There have been significant changes in
Scotland's agriculture over the last decade, not least because increasing concerns over the
environmental impact of agriculture has led to the introduction of various agri-environment
schemes across Europe. Their main objectives include reducing nutrient and pesticide
emissions, protecting biodiversity, restoring landscapes and preventing rural depopulation.
In virtually all European countries the uptake of schemes is highest in areas of extensive
agriculture (as is the case in much of Scotland), where biodiversity is still relatively high, and
lowest in intensively farmed areas where biodiversity is low (Kleijn & Sutherland 2003).
These agri-environment schemes will in turn have a significant impact on the potential need
for, and costs and benefits of, different management strategies to reduce economic losses
to wildlife. For instance, Environmentally Sensitive Areas (ESAs) were introduced in 1987
and ten currently operate in Scotland
(http://www.scotland.gov.uk/Topics/farmingrural/Agriculture/Environment/Agrienvironmen
t/ESA/Introduction). However, a study in Northern Ireland found that the ESA scheme had
no demonstrable effect on the abundance of Irish (mountain) hares, a target species, but
that the abundance of foxes and rabbits was significantly greater within ESAs compared to
the wider countryside, possibly because reduced livestock stocking densities, reduced
overgrazing and field boundary enhancements create more favourable conditions for both
species (Reid et al. 2007). This has implications for farm economics: whilst farmers, crofters
and common grazing committees within designated areas in Scotland receive financial
benefits for implementing these schemes, the potential economic costs in terms of
increased losses to wildlife are unclear. Although the ESA scheme was closed to new
entrants on 31 December 2000, a number of similar features have been incorporated into
the Scotland Rural Development Programme 2007-2013
(http://www.scotland.gov.uk/Topics/farmingrural/Agriculture/Environment/Agrienvironmen
t/ESA/Introduction), even though there are few data on which to assess the impact of
different agri-environment schemes on the abundance of wildlife or the potential for
economic losses to farmers. However, the limited data available suggest that agrienvironment schemes are further benefiting common species such as foxes and rabbits.
Patterns of agriculture also inevitably change in response to market forces, and farming in
Scotland remains in a state of flux (Scottish Natural Heritage 2009). For instance, since 2000
the area of arable crops has declined by about 10% and the total area of forage grassland
increased, whereas the area of rough grazing registered as agricultural land, which includes
grass, heather and blanket bog, has remained more or less constant. However, recent
increases in cereal prices and the abolition of set-aside from 2008 are likely to lead to a
recovery in the area of arable crops. The number of beef cattle in Scotland declined by 9%
between 2000 and 2007, and the total number of sheep by 18% over the same period. In
2007 there were two million fewer sheep and lambs than ten years previously. Numbers of
dairy cattle, which declined significantly during the late 1990s, have currently stabilised at
around 5% below their 2000 level. The livestock herd sizes have also fluctuated over this
period, with cattle numbers rising by 15% per holding since 1997 and sheep numbers per
holding falling by 7.7% since 1998 (Scottish Natural Heritage 2009). These changes will in
their turn influence the need for farmers to control different species of wildlife on their
farm: fewer sheep and lambs imply that losses to predators such as foxes will be lower, but
increases in the area of cereals and forage grassland suggest that losses to grazers such as
rabbits will be more significant. These changes in agricultural practices are important, for
instance, when considering the role of foxes in controlling rabbit numbers.
When assessing the potential impact of a ban on snaring on Scottish agriculture, it is also
important to consider the contribution from each sector to the total farming output. In 2009
this was £2.26 billion, of which beef contributed 26% (28% in 2000), cropping 21% (22% in
2000), dairy 12% (11% in 2000), horticulture 11% (6% in 2000), sheep 10% (12% in 2000),
non-agricultural 7% (5% in 2000), poultry 4% (6% in 2000), other agricultural 4% (4% in
2000), pigs 3% (3% in 2000) and other livestock and products 3% (2% in 2000) (Donnelley
2010). Thus, for instance, predation by foxes on rabbits and rodents directly benefits 7074% of Scottish agriculture in terms of output (the beef, cropping, dairy, horticulture and,
possibly, other agricultural sectors), whereas it only has the potential to adversely affect 17-
24% of Scottish agricultural output (the sheep, poultry, pigs, and possibly other agriculture,
and other livestock and products sectors). Obviously, the impact of different species varies
between members of the farming community (Baker et al. 2008), but overall the impact of
fox predation on major agricultural pests such as rabbits and rodents has the potential to
benefit between 3.1 and 4.4 times as much of Scotland's agricultural output as it has the
potential to have an adverse impact through predation on livestock. However, even this is
not the full picture: as we show below, foxes also directly benefit sheep producers through
reductions in the impact of rabbits on pasture. At 1998 prices, enclosure trials suggested
that losses of rabbit grazing on crops was £2.00 per rabbit but 70% higher (£3.40 per rabbit)
for grazing on grass grown for silage (Dendy et al. 2003a; Dendy et al. 2004).
In this review, we consider forestry as an agricultural crop. The total gross value added
(GVA, i.e. the difference between the value of goods and services produced and the cost of
raw materials and other non-labour inputs which are used up in production) associated with
Scottish timber was estimated to be around £460 million at 2007/2008 prices, or 0.5% of the
total GVA for the Scottish economy. Forestry also supplied significant other, non-economic,
benefits from recreation and access (Edwards et al. 2008).
We also briefly consider the potential impact of a ban on snaring on freshwater aquaculture
production. Scotland is currently the largest producer of farmed salmon in the EU,
producing 129,000 tonnes in 2007. To stock the salmon farms, 135 freshwater production
units in Scotland produced 38.1 million smolts in 2007, which were then transferred to the
sea cages. In 2007 freshwater farms also produced 7414 tonnes of brown trout, 298 tonnes
of rainbow trout and 4 tonnes of Arctic charr for table and fishery purposes
(http://www.snh.gov.uk/land-and-sea/managing-freshwater/freshwater-aquaculture/).
Aquaculture accounts for almost 40% of Scotland's food exports, and the sector's total
output is worth about £400 million a year at farm-gate prices
(http://www.scottish.parliament.uk/business/officialReports/meetingsParliament/or10/sor0310-02.htm); the majority of this is due to salmon production, but the direct
contribution of freshwater aquaculture to the Scottish economy is not clear.
Agricultural losses
Agricultural losses to foxes
There is no evidence of any significant changes in overall fox numbers over the last thirty
years. Macdonald et al. (1981) estimated that there were 252,000 adult foxes in Britain. A
subsequent study estimated 240,000 adult foxes, of which 23,000 were in Scotland (Harris
et al. 1995), and a third estimated 258,000 adult foxes (Webbon et al. 2004). There have,
however, been local changes in numbers. For instance, fox numbers (and other predator
populations) were greatly reduced in parts of east Scotland and East Anglia by gamekeepers
and others when the use of gin traps and poisons was widespread; numbers of foxes started
to recover in these areas from the late 1960s onwards (Lloyd 1980; Tapper 1992). There
have also been declines in some areas, such as in southern England (Baker et al. 2002).
The impact of foxes on agriculture has been the subject of a great deal of debate. Before the
issue became politicised by the call for a ban on hunting foxes with dogs in Scotland, and
then England and Wales, foxes were generally perceived by farmers as being a minor
problem. For instance, a survey of 892 farmers in the early 1970s by NOP Market research
Ltd (Anon. undated b) found that 70% of all farmers did not consider the number of foxes on
and around their farms to be harmful; only 27% considered foxes harmful. A regional
breakdown showed that 87% of Scottish farmers suffered no loss to foxes, compared to 70%
in northern England, 63% in southern England, 62% in the Midlands, and 57% in Wales and
western England. The fact that Scottish farmers reported lowest levels of losses to foxes
(Anon. undated b) is perhaps not surprising: fox densities are generally low in Scotland
(Harris et al. 1995). Hewson (1986) showed that there was one fox den per 32 km 2 in deer
forest and areas used for deer-sheep, one den per 23 km2 in grouse moor and areas used for
grouse-deer, one den per 20 km2 in grouse moor-agricultural land, and one den per 10 km2
in agricultural land. However, higher densities do not necessarily mean that farmers
consider foxes to be a pest. In Wiltshire, for instance, most farmers did not consider the fox
to be a pest at all. Only 10% of farmers believed the fox to be their worst pest; most said it
was rabbits (Baker & Macdonald 2000). This mirrors findings for Midlands farmers
(Macdonald 1984).
As we showed at the start of this review, there are still claims of widespread losses to foxes,
especially of lambs, even though it is nearly 30 years since the Ministry of Agriculture
Fisheries and Food estimated that 20% of newborn lambs died soon after birth, and that of
these deaths only 5% were due to ‘misadventure and predation’: this included dog and fox
predation (MAFF 1983). The Ministry for Agriculture Fisheries and Food estimated that
around £103 million of gross income was lost by farmers as result of lamb deaths every year
in Britain due to factors other than fox predation.
All the subsequent work on fox predation on lambs, much of which has been done in hill
areas of Scotland, supports this early assessment. Hewson (1984) compared two areas in
west Scotland: the foxes killed a minimum of 1.3, 1.8, 0.8 and 0.6% of the lambs estimated
to have been born in 1976-1979 respectively. Hewson (1984) found that lambs less than 10
days old were most susceptible to predation; White et al. (2000) came to similar
conclusions, showing that lambs were only susceptible to predation by foxes during their
first two to three weeks of life. Hewson (1990) subsequently worked on a large sheeprearing estate in Scotland: fox control was stopped for three years but no evidence of
increased predation on lambs was detected, and in the absence of control less than 1% of
lambs were killed each year by foxes.
A four-year study in the 1990s on losses of Scottish blackface lambs on two Scottish hill
farms (in Midlothian and West Perthshire) also suggested that fox predation is a not a
primary cause of death among lambs (White et al. 2000). Overall lamb mortality rates from
birth onwards were 10.2 % in Midlothian, 9.3% in West Perthshire; minimum rates of fox
predation were 0.6% and 0.2% respectively. The maximum losses in revenue due to fox
predation in any one year were £298 in Midlothian, £112 in West Perthshire, i.e. 1.5% and
0.6% respectively of the total potential revenue from lamb production that year (White et
al. 2000). Using findings across a range of studies, these authors estimated that fox-related
costs per farm, including lost output and protection costs, averaged £53 in lowland areas
and £302 in upland areas each year. These costs are relatively small in relation to total farm
income, and are also overestimates, as lamb prices are maintained artificially high by
support payments and other support measures of the Common Agricultural Policy
(Macmillan & Phillip 2008).
White et al. (2000) also found that missing lambs came from larger litters; these may be
more liable to fox predation because of the ewe's greater problems in maintaining vigilance,
and because they tend to be smaller (Nash et al. 1996; Simm et al. 1996). The same has
been reported for Merino ewes: they were less able to care for twins, resulting in a loss of
contact between the ewe and its lambs and a consequently higher rate of mortality for
twins as opposed to single lambs (Stevens et al. 1982). White et al. (2000) recorded lamb
losses of 10.2% in Midlothian and 9.3% for West Perthshire, which were comparable with
the results of other studies. Scottish blackface sheep occupy poorer ground, usually in the
north and west, than Cheviot ewes (Coppock & Lang 1976), and so probably suffer higher
levels of losses because ewes in good condition probably provide better care for their
lambs, both against predators and generally (Moore et al. 1966; Alexander et al. 1967;
Rowley 1970). A mortality rate of 15 to 20% is not uncommon among Scottish Blackface
lambs (Houston & Maddox 1974). White et al. (2000) also note that high levels of lamb loss
are a welfare issue, and suggested that changes to farming practice or animal husbandry
might help to minimise them and should be considered seriously. Lambs born as twins or
triplets were more susceptible to predation or misadventure, suggesting that slight
modifications to existing husbandry practices, such as keeping ewes with twins or triplets
indoors for the first week or so after birth, rather than for 24 to 36 hours, might significantly
reduce lamb losses during the first few weeks of life. Such a change in practice would be
especially beneficial on farms where multiple births were relatively common. Thus simple
changes in farming practices could lead to improvements in welfare and reduce lamb losses.
The pattern of predation on lambs reported from Scotland is similar to that reported
elsewhere in Britain e.g. Macdonald (1984). A study of fox predation in three regions of
Britain found that the mean percent of lambs lost to foxes by sheep farmers was 0.6%
(range 0-14.5%) in mid Wales, 0.4% (0-5.2%) in east Midlands and 0% (0-28.6%) in west
Norfolk (Heydon & Reynolds 2000a). This study also illustrates a point made by a number of
other studies, in that whilst losses are generally low, a few farmers suffer significantly higher
levels of loss. A number of studies have suggested that these occasional high levels of loss to
predators are associated with poor standards of husbandry (e.g. Baker et al. 2008).
Whilst it has long been known that foxes can and do kill livestock, the key issues are the
economic impacts of these losses and deciding on the most cost-effective solutions (which
may, of course, include doing nothing). Economic analysis is a useful tool to aid decisions on
what to do about wildlife impacts. The first stage in this process is estimating the actual
losses to foxes. The analyses presented in McDonald et al. (1997) have now been updated
by a series of studies on fox predation on all aspects of the livestock sector, so that we now
know more about the economic impact of foxes on agricultural interests in Britain than
anywhere else in the world. Since these studies described below are based on extensive
questionnaire surveys of farmers rather than field studies on losses, they are particularly
valuable in that they quantify the perceptions of livestock farmers and the impact of fox
predation.
Moberly et al. (2003) found that farmers generally reported that fox predation on lambs
ranged from 0.0008 to 0.26 lambs per ewe, with 59% of respondents having lost at least one
lamb in the previous lambing. Flock size was an important factor influencing perceived rates
of loss, but whilst losses were more likely on larger farms, fewer lambs were lost per ewe.
Moberly et al. (2004a) used these data and marginal analysis to determine the total costminimising solution to reduce fox predation from the farmer’s point-of-view, in terms of
how many ewes should be housed indoors and for how long, as well as how many foxes
should be killed in addition to any lethal control already carried out. Optimal solutions
varied according to farm characteristics, including flock size and the regional location of
farms. In all cases, to minimise the costs of predation, as many ewes as possible should be
housed. However, it was not worthwhile housing them for more than a day after lambing.
They also showed that efficient fox predation management does not necessarily mean that
lamb losses should be reduced to zero, and additional fox control is not worthwhile on the
majority of farms. These detailed analyses reinforce the results of earlier, field-based
studies.
Based on perceived estimates of predation, foxes cost sheep producers across Britain
approximately £9.4 million in 1999 (Moberly et al. 2002). To put this figure into perspective,
the Ministry of Agriculture, Fisheries and Food estimated that sheep producers in the UK
lose up to 4 million lambs each year, at an annual cost to the industry of £120 million.
Deaths due to misadventure and all predators combined accounted for just 5% of these
losses; the other losses were due to a variety of management problems (MAFF 1983).
The predation of foxes on poultry is often perceived to be where they have the greatest
impact on agricultural livestock and is perhaps the greatest contributory factor in the
antipathy of farmers towards the fox. So in Wiltshire, for instance, where farmers' opinions
of the fox were influenced by personal stock loss, their main concern was chickens, even
though these were generally kept on a non-commercial scale (Baker & Macdonald 2000).
Until recently, predation was not a problem for most large-scale poultry producers, because
the birds were kept in intensive indoor units which are secure against foxes. However, the
past 20 years have seen a marked growth in the British free-range poultry industry,
especially in egg production, for which free-range hens make up nearly a fifth of the British
flock (Anon. 2001). Indoor-reared poultry (i.e. the great majority of the national flock) are
generally safe from fox predation. A survey of commercial producers of free-range eggs,
chickens, turkeys and geese showed that mean reported bird mortality was less than 2 per
cent for all the producers, but there were marked differences between them. Egg producers
reported losing many more birds to foxes than other types of producer (up to 1000 birds in
a laying cycle). On average, egg and goose producers lost the highest proportions of their
total flocks (0·5 per cent). The extent of predation was not associated either with large-scale
estimations of the density of the fox population or with variations in the farms’ habitat.
Chicken predation was not linked to differences in types of housing or fencing. However,
there was a positive association between losses due to other causes and chicken predation.
The results suggest that changes in farm management would be the most cost-effective
means of reducing fox predation, rather than greater fox control (Moberly et al. 2004b).
Across Britain as a whole, the total cost of fox predation per annum was £653,000 to egg
producers, £221,000 to turkey producers and £440,000 to goose producers. The financial
cost of fox predation to table chicken producers was negligible (Moberly et al. 2002).
Whilst fox predation on piglets is believed to be increasing with the trend towards more
outdoor rearing, there is little evidence to support this. One estimate was that pig farmers
lose £5.3 to 6.8 million each year to natural causes compared to only £150,000 to fox
predation i.e. only ~3% total losses (Sheppard 1993). A survey of 48 outdoor pig producers
found that, on average, 0.3% of piglets born were reported killed by foxes, with losses of up
to 5%. Farms with more sows were more likely to have experienced predation. Higher losses
were experienced on farms with villages in their surroundings, which may be due to foxes
being blamed for predation by dogs. This analysis showed that electric fencing is an effective
preventative measure against fox predation. Piglet losses to foxes decrease with increasing
expenditure on fence maintenance, but at a declining rate. Therefore, a high level of
expenditure on fencing to prevent fox predation is not justifiable in economic terms and the
best strategy financially for producers is to tolerate some losses to foxes. In some cases, it is
not worth spending any more on fencing than would be spent if losses to fox predation
were not taken into account. Predation of piglets by foxes costs British agriculture £966,000
per year (Moberly et al. 2002).
Thus quantified analyses of all the major sources of fox predation on livestock show that fox
predation has a direct economic cost to British agriculture of approximately £12 million per
annum. However, since the bulk of fox diet is made up of rabbits, which cause
approximately £115 to £820 million damage to UK agriculture each year, fox predation also
brings significant indirect economic benefits to farmers. Macdonald et al. (2003) estimated
that killing a young fox may cost a farmer £156 to £886 in avoidable losses to rabbit grazing.
There is also a widespread perception that foxes carry many diseases and that they may act
as a reservoir from which infectious agents can spread into domestic animals. A study of 843
rural and urban foxes found that 86.8% of the foxes harboured parasitic helminths (thirteen
different species, including four that have not previously been found in the UK), but none
were of significance to farmers (Richards et al. 1995). In Wiltshire, 30% of farmers thought
that foxes should be controlled because they spread disease (Baker & Macdonald 2000);
whilst they identified 14 diseases of concern, none of these posed a serious threat to human
or livestock health. More recently, a survey of zoonotic parasites in red foxes did not record
Echinococcus multilocularis in 588 fox carcasses, although E. granulosus was suspected in
six. No evidence could be found for Trichinella spp. in 587 fox muscle digests or for
Toxoplasma in a sub-set of 61 random fox tongue biopsies (Smith et al. 2003). So there is no
evidence of foxes playing a role in the spread of parasites of importance to Scottish
agriculture.
Agricultural losses to mink
There are few quantified data on the agricultural losses to mink. In the mid-1980s, losses of
domestic poultry and waterfowl constituted 61% of the requests for advice to MAFF's
Wildlife and Storage Biologists (Harrison & Symes 1989). However, financial losses were
relatively low, and the units most affected were small and run as a sideline. Furthermore,
the rise in the number of free-range poultry units to the mid-1980s did not lead to a rise in
the number of reported mink problems. Damage to farmed fish formed 5% of the reports.
The other reports were not of agricultural losses (Harrison & Symes 1989). Losses of
domestic fowl was generally low, despite a possible bias to report larger predation events.
Of 75 trout farmers interviewed, 46% said that mink had visited their farm the previous
year, and 16% regarded mink damage as a serious problem, although most farmers reported
that other predators, such as herons, were of greater significance. Whilst the main problem
posed by mink was predation on, or damage to, fish, there were three reports of damage to
fish cages/netting (Harrison & Symes 1989).
Similar results were reported by Macdonald et al. (2004): a 1996 survey of 32 farmers along
the River Thames in west Oxfordshire showed that, whilst 29 (91%) considered mink to be a
pest, most cited losses of wildlife as the main problem: only 12.5% cited damage to poultry.
Macdonald et al. (2004) also reported that mink were believed to have made the keeping of
outdoor poultry almost impossible on Harris and Lewis. Before mink colonised the islands,
90% (3600) of the 4000 registered crofts were estimated to have kept poultry; by 2004
fewer than 10% (400) continued to do so. Based on an average flock size of 10 birds, the net
annual cost of this constraint to the crofting economy on the two islands was estimated to
be £586,000 i.e. £183 for each of the 3200 crofts that ceased to keep poultry.
Harrison & Symes (1989) concluded that "no major costs, whether through damage, control
costs or hidden constraints, have been identified, so judged by these criteria it seems
reasonable to conclude that feral mink are as yet a relatively minor problem. As a result, it is
difficult to justify on economic grounds more than local attempts at control." It is important
to note that this survey and the conclusions were based on the mink population in the mid1980s; since the mid-1990s there have been substantial declines in mink numbers in
Scotland (Battersby & Tracking Mammals Partnership 2005), suggesting that agricultural
losses to mink are lower today than when Harrison & Symes (1989) carried out their survey.
Agricultural losses to rabbits
Across Britain as a whole, rabbit numbers have been in decline since the mid-1990s
(Battersby & Tracking Mammals Partnership 2005). At the local scale, rabbits are most
abundant in grassland areas with small fields and the very short, homogeneous swards
created by intensive sheep grazing during autumn and winter. At the landscape scale, high
rabbit numbers were associated with sites with field margins and a predator removal policy.
Thus, current pasture management practices appear to create favourable conditions for
high rabbit densities, and consequently boost both rabbit numbers and their economic
impact (Petrovan et al. 2010).
The introduction of myxomatosis highlighted the significant impacts rabbits can have on
agricultural output. Scotland was affected earlier than much of England, owing to the extent
of deliberate transmission of the disease, and the decimation of rabbits appears to have
been viewed with greater equanimity in Scotland than elsewhere in Britain, probably
because the demanding and marginal nature of much of Scottish farming meant that rabbit
depredation hit Scotland particularly hard (Bartrip 2009). The spread of myxomatosis in
1953 and 1954 was followed by reported increases in crop yields of up to 30%; in 1955
MAFF estimated an extra value for the UK cereal crop of £15 million, which was largely due
to the elimination of rabbits (Trout 2003). The persistence of myxomatosis meant that
rabbit damage was virtually eliminated for the next 20 years. However, as rabbit numbers
started to increase, so did agricultural losses. In the 1980s, the total cost of rabbit damage
to agricultural crops in Britain was estimated to be approximately £100 million per annum,
based on a cost of £5.00 per rabbit (Rees et al. 1985). In 1990/1991 the total cost to Scottish
agriculture was estimated to be £12 million; had rabbit populations been at premyxomatosis levels, levels of damage would have been around £38 million (Kolb 1994). The
estimated cost to British agriculture was updated to approximately £115 million per annum
in 2003, with the total cost of rabbit control being approximately £5 million per annum
(Hansard 2003). Much higher estimates have been produced e.g. Pimentel et al. (2001)
estimated the total damage from rabbits in the UK to be US$ 1.2 billion per year (£820
million); two-thirds of these losses were to crops, one-third to pasture.
Most of the loss to rabbits is due to grazing crops and pasture. Winter wheat, barley and
oats appear to be most vulnerable, rye and triticale suffer smaller losses, and spring barley
appears to be the least susceptible to rabbit damage (Anon. undated c). Rabbit damage
early in the growth of crops contributes most to the yield loss, with damage after April being
less significant (Crawley 1989; Bell et al. 1998). Crawley (1989) showed that brief early
grazing on winter wheat led to eventual yield losses of 17% to 30% over three years:
increasing the duration of exposure to rabbit grazing caused a roughly linear decline in grain
yields. The decline in the competitive ability of the cereal crop led to a progressive increase
in the abundance of grass weeds, and increased weediness led to further yield reductions of
up to 47%. A three-year enclosure trial of rabbit grazing on spring barley showed that the
annual loss was 0.5% per rabbit per hectare, or a yield loss of around 25 kg per rabbit. This
was a financial loss of £2.00 per rabbit at 1998 prices (Dendy et al. 2004).
Whilst the effect of rabbit grazing on pasture is less obvious than on cereals, impacts can be
equally significant and high densities of rabbits can substantially reduce the carrying
capacity of pasture for domestic stock. A three-year enclosure trial showed that the annual
yield loss of grass grown for silage was 1% per rabbit per ha, the yield loss per rabbit was
around 200 kg, and the financial loss was £3.40 per rabbit at 1998 prices (Dendy et al.
2003a). A three-year enclosure study on a rye-grass re-seed showed that there was a
significant reduction in ryegrass proportion in grazed swards following the first winter of
grazing, while clover, other grasses and weeds were enhanced. In the second year,
protection of grazed swards led to a restoration of yields, although the botanical
composition remained altered. The exposure of previously ungrazed plots in the final year of
the experiment showed that these swards were particularly attractive to rabbits and
suffered the greatest yield losses relative to the protected plots (Bell et al. 1999). Thus
protection of ryegrass swards from rabbit damage is important at the establishment phase,
but a degree of recovery is possible by providing protection at a later stage, although the
ryegrass component is still impaired in swards which suffer early damage (Bell et al. 1999).
Furthermore, scratching and burrowing can degrade pasture still further by encouraging the
establishment of weeds such as nettles, thistles and ragwort (Anon. undated c). The impact
of rabbits on cereals and pasture is discussed in more detail by Trout (2003) and Dendy et al.
(2003b); both reviews stress the importance of rabbit control before damage is obvious
rather than as responsive strategy.
The impact on upland rough grazing has been less well quantified: the loss of the "early
bite", when stock are first let out on the hill in spring to eat the first flush of growth, may be
particularly significant (Trout 2003), and Iason & Hester (1999) estimated that rabbit offtake
in their upland study sites in Scotland may be equivalent to sheep offtake. Trout (2003) even
describes a situation in the Yorkshire Dales where over 5000 rabbits were shot one summer:
this equates to 500 to 800 sheep. Since the maximum stocking density for the same area
was 400 ewes, the offtake by rabbits exceeded that of sheep.
There is little quantified information on the economic impact of rabbits on vegetable
growers. Root crops, brassicas and market garden crops can all suffer severe damage from
rabbits, both to the growing plants and the marketable end product (Anon. undated c).
However, whilst over half of 55 UK organic vegetable growers interviewed in 1987 thought
they lost >10% of their revenue to pests, their most serious problems were weeds, in
particular chickweed, couch grass and thistles, with slugs and birds next most important,
followed by insects and diseases. Rabbits were included last with other causes of crop losses
as being of marginal importance (Peacock & Norton 1990). This seems to be supported by a
trial in Wales comparing selected varieties of vegetables grown from organic seeds in a four
bed system. Of 4 varieties of courgettes, 1 squash, 4 leeks, 4 onion sets, 3 beetroots, 5
carrots, 2 parsnips, 3 broad beans, 5 lettuce, 2 French beans, 2 oriental leaves, 5 cabbage
and 3 calabrese/broccoli, rabbit damage was only recorded for two varieties of leeks early in
their growth, and two varieties of calabrese/broccoli (Robertshaw & Hitchings 2004).
Natural England also report that rabbits can damage or kill planted nursery stock and young
trees, that damage to the bark of large trees can be serious, that semi-mature hedgerows
may also be vulnerable, and that in extreme circumstances, rabbits may prevent natural
regeneration in woodlands (Anon. undated c). Sumption & Flowerdew (1985) documented
the impact of reduced rabbit numbers following myxomatosis on the natural regeneration
of a wide range of woodland seedlings, with some woodlands showing natural regeneration
for the first time in decades. However, the actual economic impact of rabbits (and most
other wild mammals) on commercial forestry in Scotland is unclear: whilst there are some
data on the cost of browsing and bark stripping to timber production, the variability in the
results from different studies underlies the difficulties in accurately assessing the economic
losses caused by wild mammals to commercial forestry (Gill 1992a), although one estimate
put the annual costs of rabbit damage to forestry as £90 million in 2001 (White & Harris
2002).
Most studies however simply quantify damage to trees rather than the longer term
economic losses. For instance, a survey of damage to Forest Enterprise woodlands across
Britain showed that damage from rabbits and hares was generally lower in the three
Scottish conservancies than the four in England and Wales. In Scotland, rabbits were only
considered to be a bigger problem than hares in the Mid Scotland conservancy, and here
damage levels from rabbits and hares were the lowest recorded in Britain. In comparison,
damage levels by red and sika deer in Mid Scotland were thirteen times higher than those
due to rabbits and hares (Wray & Harris 1994).
Rabbits will readily eat the bark from apples, and in Britain bark stripping by rabbits can
occur on trees of a diversity of sizes and ages, but there is little data available to show how
susceptibility alters with age for different species. Beech however appears to be more
susceptible for longer than other broadleaves (Gill 1992b). Burrowing by rabbits can also
undermine root systems (Anon. undated c), and damage to walls, banks and other
structures can be substantial (Trout 2003). However, the economic losses due to damage to
infrastructure in agricultural areas are unknown.
Agricultural losses to brown hares
Brown hares are listed in Appendix III of the Convention on the Conservation of European
Wildlife and Natural Habitats 1979 (the Bern Convention) and identified as one of the "116
of our most threatened and endangered species" included in the first list of Biodiversity
Action Plan species (Anon. 1995). Whilst the aim of the Species Action Plan was to double
spring numbers by 2010, some monitoring schemes suggest that brown hare numbers are
continuing to decline, albeit slowly (Battersby & Tracking Mammals Partnership 2005).
During the second half of the 1800s, only land owners could shoot hares: tenant farmers
could not. This led to very high hare densities, and in some areas at least hares were
agricultural pests. Any losses had to be borne by tenant farmers, who farmed about 85% of
Britain. The Ground Game Act 1880 allowed tenant farmers to shoot hares for the first time,
and this had a big impact on numbers, at least locally. Across Britain as a whole, brown
hares declined by roughly 80% during the 1900s (Hutchings & Harris 1996), and there is now
little evidence of them being a significant agricultural pest (Harris & McLaren 1998). In a
survey of 84 farmers in the midlands, none listed brown hares as a major pest, and only 1
farmer considered brown hares a pest at all (Macdonald 1984).
Whilst brown hares are most common in agricultural land (Hutchings & Harris 1996), and
spend much of the late winter feeding on winter cereals (Tapper & Barnes 1986), there is
little information on the effects of their grazing on crops and pastures. Brown hares prefer
arable farms, especially those with wheat, beet or fallow land (Vaughan et al. 2003), and
avoid short homogeneous vegetation (Smith et al. 2004), although they prefer to graze
where the vegetation is shorter, probably because of the reduced risk of predation
(Frylestam 1976; Hewson 1977). When available, brown hares preferentially eat wild grasses
and herbs rather than cultivated forms, with grasses predominating in the winter, herbs in
the summer (Frylestam 1986; Tapper 1991).
When brown hares do graze cereals and cultivated grass, the impact is generally so low that
it is not noticed by farmers (Tapper 1991). When present in large numbers, brown hares can
occasionally cause damage to sugar beet and other root crops (Tapper 1991), and crops
such as vines and peas (Harris & McLaren 1998). Hewson (1977) examined the preferences
of brown hares for barley treated with varying amounts of fertilizer, between oats and
barley, between different varieties of each cereal and seven varieties of turnip on farms in
north-east Scotland. Hares had no particular preference for oats or barley, and the amount
of grazing on barley was not correlated with the final yield of straw and grain. Selection
among turnips reflected palatability rather than nutrient content: the two preferred
varieties had purple roots, those least favoured green roots. Hewson (1977) concluded that
hare damage to turnips was not of economic importance in Scotland, and in mid-Wales
hares (and rabbits) were not listed as pests of root crops
(www.ecodyfi.org.uk/growing/downloads/week6.pdf). In Scotland, damage to root crops
from deer appears to be a far more significant issue (Scott & Palmer 2000).
A more quantified analysis of the economic impacts of hare grazing was undertaken in
Poland, where Kałuzioski & Bresioski (1976) showed that, with a winter density of
approximately 100 hares per km2, losses of cereal and rape to hares, and probably alfalfa,
was economically negligible, even though each hare consumed 144 g of green matter per
day. For comparison, the mean mid-winter density of hares in the eastern arable areas of
Scotland in the early 1990s was dramatically lower, just 5.24 hares per km2; mean densities
were even lower elsewhere in Scotland (Hutchings & Harris 1996).
Brown hares appear to be increasingly common in commercial forestry. However, since
early losses due to browsing damage can be recouped later, as for rabbits (see above) most
studies simply report levels of browsing damage rather than actual economic impact. A
survey of hares in Forest Enterprise woodlands throughout Britain showed that, of 181
commercial plantings, 56% contained brown hares in low numbers. They were only common
in 12 plantings (7%), and 10 of these were in the East England Conservancy. In Scotland,
brown hares were considered common in the South, but in much lower numbers in the Mid
and North Scotland conservancies. Whilst brown hares caused low level damage to
plantings in some areas of South Scotland Conservancy, they caused little damage in Mid
Scotland and did not cause damage in North Scotland (Wray & Harris 1994).
Monitoring of Corsican pines in East Anglia showed that browsing damage can be reduced
by choosing planting stock that is less susceptible to browsing, and that hare damage is only
significant in the early stages after planting: over a longer time scale, the early reduced
growth rate caused by browsing appears to be recouped (Wray & Harris 1994). Brown hares
were found to select parts of an East Anglian commercial forest with a high diversity of
grasses, and were most common in young plantings and mature plantings post-thinning,
where the ground cover consisted predominantly of grasses. They were rare or absent from
plantings where the ground cover was predominantly bracken. Thus the type of ground flora
is likely to be an important contributory factor in determining whether a particular piece of
woodland contains brown hares and hence the extent of any damage that occurs (Wray &
Harris 1994).
Hares also browse broadleaf trees. In Poland, Szukiel (1976) reported that browsing damage
on 1 to 5 year-old saplings of broadleaf trees can locally be significant, and that preferred
species such as oak or beech can be browsed almost to ground level, making regeneration
impossible. Hares are also said to attack peaches and plums (Gill 1992b), and browsing of
cherries has been reported in Poland (Kałuzioski 1976).
Agricultural losses to mountain hares
Mountain hares are listed in Appendix III of the Convention on the Conservation of
European Wildlife and Natural Habitats 1979 (the Bern Convention) and in Annex V of the
European Communities Directive 92/43/EEC on the Conservation of Natural and Seminatural Habitats and of Wild Flora and Fauna 1992 (the Habitats Directive) as a species 'of
community interest whose taking in the wild and exploitation may be subject to
management measures'. This means that certain methods of capture are prohibited and
may only take place under licence, and Member States are required to ensure the
conservation status of mountain hares is maintained and that their populations are
managed in a sustainable manner. The mountain hare also became a UK Biodiversity Action
Plan species in 2007, in part because mountain hare populations are thought to be declining
in Scotland, which holds more than 99% of the British population (Harris et al. 1995;
Battersby & Tracking Mammals Partnership 2005).
Although widespread throughout Scotland, mountain hares are typically more numerous in
the central and eastern highlands, with fewer hares in west and south Scotland (Harris et al.
1995); their highest densities are associated with heather moorland managed for red grouse
(Watson et al. 1973). Mountain hare density varies with region, altitude, and underlying
geology (Watson & Hewson 1973), with generally fewer hares at lower altitudes and over
acidic rock. Counts across Scotland showed that mountain hare density can range from 0 to
300 hares per km2 (Watson et al. 1973). However, whilst mountain hares and hill sheep
preferred the same types of moorland vegetation, the bulk of available forage in the hill
pastures was removed by cattle and sheep, and grazing by mountain hares on hill pastures
declined sharply when sheep were introduced: there was a negative correlation between
sheep and cattle numbers and mountain hare numbers (Hewson 1989). Whilst there are no
data to show the economic benefits of culling mountain hares to reduce losses to Scottish
agriculture, their absence from lowland areas and their negative interactions with stocking
densities suggest that agricultural losses from mountain hares are generally low.
The conservation of mountain hares appears to conflict with the afforestation of upland
areas, and this has increased the demand for killing mountain hares (Newey et al. 2008),
although there are few data to show that mountain hares have a significant economic
impact on forestry. Hewson (1962) found that gorse and juniper, supplemented by soft rush,
were the main food items of mountain hares in snowy conditions, with ling keenly sought in
areas where the snow has been cleared by wind. However, mountain hares also feed on
twigs of young trees in winter when other plants are buried in snow (Gill 1992b). A survey of
Forest Enterprise woodlands throughout Britain showed that damage from rabbits and
hares was generally lower in the three Scottish conservancies than the four in England and
Wales, and the South and Mid Scotland conservancies had lower levels of damage to trees
from rabbits and hares than any of the other five conservancies. Damage in the North
Scotland conservancy was on a par with the rest of Britain, predominantly due to mountain
hares, which caused unacceptable levels of damage in two forest districts (Wray & Harris
1994). Afforestation may actually be beneficial to mountain hares in the short term: during
the early plantation stages large-scale afforestation improves diet quality and body weights
of young mountain hares compared to those living on moorland (Hulbert & Iason 1996).
However, hare numbers decline as the forest matures, and the current pattern of large scale
afforestation is likely to lead to large areas of habitats unsuitable for mountain hares
(Hulbert et al. 1996a, b).
Rao et al. (2003a) found that, when mountain hares browse birch, this may potentially
suppress tree growth and tree regeneration. Whilst downy birch is used to establish and
regenerate native woodlands, the impact of mountain hares on the establishment of Scots
pine or birch woodlands in the uplands of Scotland is likely to be minimal where hares occur
at moderate densities (Rao et al. 2003b). Rao et al. (2003a) suggest that, although, tree
planting can be synchronized with temporary hare control, it may be difficult to reduce hare
numbers effectively. However, adjusting planting strategies appears to be more effective:
using a lower planting density reduces browsing damage because the rate of browsing in
winter (when most browsing occurs) increases with increasing tree density. Damage can
also be minimized by planting them in tall vegetation where they are less visible and
accessible to mountain hares (Rao et al. 2003a); as with brown hares, mountain hares prefer
to graze in open areas, presumably to reduce the risk of predation (Hewson 1976).
In Ireland broadleaved species, particularly oak and, to a lesser extent, beech were most
susceptible to browsing by Irish (mountain) hares. Damage to conifers was negligible, with
the exception of larch. Irish hares did not favour evergreen conifers as browse, as Scots pine
and Norway spruce, the most numerous conifers, both showed less than 1% damage
(Strevens & Rochford 2004).
The wider economic perspective
There are a number of general ethical and economic issues to consider. In a review of the
effectiveness of culling mountain hares to prevent the spread of tick-borne diseases,
Harrison et al. (2010) concluded that widespread culling of wildlife is not necessarily
effective in reducing disease or improving economic returns. In addition, ineffective control
programmes waste time and resources, and are ethically questionable when large numbers
of animals are killed (Harrington et al. 2009). When discussing problems caused by foxes,
Natural England notes that, whilst there are number of legal methods by which foxes can be
killed, it is important to assess whether the problem could be solved by non-lethal means,
such as better protection of vulnerable animals, before embarking on a culling programme.
Non-lethal methods can provide a long-term solution and avoid the need for continuous
culling (Anon. undated d).
It is also important to put the economic costs of Scottish wildlife into a broader perspective.
Whilst the agricultural losses attributed to wild mammals may appear large in absolute
terms, and are important to individual producers, this must be seen in the context of a UK
food economy currently worth over £150 billion annually (DEFRA 2006). Gorman & Raffaelli
(2008) also point out that losses to wildlife are small in comparison to overall food wastage
in Britain. In 2007 UK households were throwing away at least 3.4 million tonnes of edible
food annually, households and restaurants wasted up to a third of the food they bought, at
an annual cost of £50 billion, and supermarkets wasted up to 500,000 tonnes of food,
mainly because it approached its sell-by date. The food manufacturing industry throws away
at least one million tonnes of food, and farmers plough 30-40% by weight of all food grown
in the UK back into the fields.
It is also important to note that a number of studies have shown that agricultural losses to
wildlife are not spread randomly, with some producers suffering significantly higher losses
than others, and that those producers who suffer significant losses to wildlife also have high
losses to other causes of mortality (e.g. Moberly et al. 2004a; Baker et al. 2008). This
suggests that significant long-term economic gains could be achieved by changes in
husbandry. However, there are few data on the economic costs and benefits of different
husbandry versus control strategies (see Moberly et al. 2004a for an example). More studies
are needed to quantify the economic benefits to farmers of different approaches to
reducing economic losses to wildlife.
Also, agricultural losses can be offset, at least in part, by their economic benefits.
Appreciating the economic value of wild mammals is central to the future development of
sustainable agricultural policies, since economic values indicate both the potential for
conflict and the scope for resolution in the management of wild mammals (Macmillan &
Phillip 2008). These values change in parallel with the wider changes in society. For instance,
wild meat provides a niche in the contemporary food market; although demand is growing,
this is handicapped by a fragmented supply chain and lack of marketing. The contribution of
wild meat to the rural economy currently appears small, but its potential role within the
growing debate surrounding ethical food may have a significant impact on the future costs
and benefits of wildlife to agriculture (Macmillan & Phillip 2008).
Thus, of the 3 to 5 million rabbits shot in 1999, 22% were killed for sport, 26% for crop and
habitat protection, and 32% for both reasons (Reynolds & Harradine 1999). Only 10% of the
rabbits shot in 1995 were sold commercially, with an estimated wholesale value of
£120,000-£200,000 (Cobham Resource Consultants 1997). However, a further 80% were
kept for personal consumption or fed to animals and birds; only 10% were thrown away.
Thus the total value of rabbits in the food chain of both humans and captive and/or
domestic animals was around £1.1-£1.8 million, equivalent to £1.5-£2.6 million in 2007
(Macmillan & Phillip 2008). Comparable figures for brown hares were that 200,000-300,000
were shot in 1995, but only 4% were sold for a wholesale value of £20,000-£30,000, and
40,000 to 100,000 mountain hares were shot, again with only 4% sold for a wholesale value
of £2000-£6000 (Cobham Resource Consultants 1997). However, this may be a significant
underestimate of the number of hares shot and sold: the carcasses of 137,000 hares were
exported annually in the late 1980s (Tapper & Stoate 1992).
A survey in 2004 suggested that the sales of wild meat had increased significantly: PACEC
(2006) calculated that 34% of rabbits shot are sold to dealers, with only 29% used as food
but not sold to a dealer. Comparable figures for hares were 49% and 45% respectively. So
the economic returns from sales of wild meat will have also increased significantly.
However, these animals also have an economic value in terms of shooting. For each
shooting provider surveyed, 40 rabbits were shot as part of sporting activities, 360 by paid
employees; comparable figures for hares were 10 shot as part of sporting activities, 36 by
paid employees (PACEC 2006). It is hard to put an economic value on rabbits and hares
killed for sporting purposes, but shooting is of particular significance in Scotland, where 4.4
of the 7.8 million hectares are influenced by shooting and 0.7 million hectares are directly
managed for shooting; this is the largest area in Britain. Of the 480,000 people who shoot in
the UK, nearly half (42%) do some shooting in Scotland, although not every year, and a
quarter of those who live and shoot in England also travel to Scotland to shoot (PACEC
2006). In addition, hare shooting attracts European visitors (Harris & McLaren 1998), who
pay for hare shooting. Overall, it has been argued that shooting in Scotland involves 1.5
million gun days, worth £240 million to the Scottish economy (PACEC 2006). However, these
figures may be generous: a recent report by Scottish Natural Heritage valued the
contribution of field sports tourism as a whole (i.e. including fishing) at £136 million
(http://www.snh.gov.uk/docs/B726802.pdf). Whichever figure is correct, it is clear that
rabbits and hares have a significant positive benefit to the Scottish rural economy, although
it is currently impossible to quantify how much this offsets losses, and the relative
distribution of economic costs and benefits between different landowners.
Snaring to protect agriculture in Scotland
General points
It is hard to assess just how widely snares are used to protect agricultural interests in
Scotland, as opposed to other purposes. For instance, in February 2008 NFU Scotland
informed the Scottish Government that it had “no robust data on the extent of snaring in
the agricultural sector” (Robertson & Anderson 2008) and Forestry Commission Scotland
does not use snares on the national forest estate.
Snaring foxes
In a defence of snaring, the Scottish Government stated that "A joint industry briefing
document The consequence of a snaring ban for rural Scotland published by the British
Association for Shooting and Conservation, the Scottish Gamekeepers Association, National
Farmers Union Scotland, Scottish Estates Business Group, Scottish Rural Property and
Business Association and the National Sheep Association in 2008, clearly sets out how
controlling predators such as foxes is vital to the shooting industry and that snaring is in
some circumstances the only tool available for such control" [our italics] (Cunningham 2010).
The interesting thing about this statement is that it makes no reference to the need to snare
foxes to protect agricultural interests, nor does it explain the circumstances under which
snaring is the "only tool" available for fox control. DEFRA (2005a) say that "Before using
snares or other capture/control methods, an assessment should be made to determine
whether the need (eg regarding damage or the threat of damage) is sufficient to warrant
action being taken, taking into account the possible welfare impact on target animals and
any risks to non-target species. Where capture/control is deemed to be necessary then an
assessment should also be made of the most appropriate method to use, again taking into
account the welfare impact on target animals and any risks to non-target species, and steps
should be taken to minimise these risks". Again, the circumstances under which snaring is
the only option available are not clear.
The other problem when trying to assess the importance of snaring foxes to farmers is that
farmers' opinions regarding the need for fox control are often contradictory, and not
directly governed by their own interests. As a result, the majority of farmers surveyed in
Wiltshire favoured a prophylactic approach to fox control, suggesting that those farmers
might have held an exaggerated view of the fox's potential impact as a pest (Baker &
Macdonald 2000). Although two-thirds did not consider the fox to be a personal pest, most
believed that foxes should be controlled everywhere, simply because they were too
numerous. It is perhaps not surprising therefore that several studies have questioned
whether widespread culling has an impact on agricultural losses to foxes. For instance,
Hewson (1986) reported that widespread fox control did not reduce complaints of lambkilling by foxes, although the destruction of foxes and cubs at breeding dens often stopped
local instances of lamb-killing. An experimental approach, investigating the effects of three
levels of fox control in south-eastern Australia, found no effect of fox control on lamb
production (Greentree et al. 2000).
Furthermore, the need to snare foxes to prevent agricultural losses are often confounded by
pooling data with shooting interests. A survey in Wiltshire found that none of the farmers
surveyed used snaring for fox control (Baker & Macdonald 2000). Heydon & Reynolds
(2000a) found that snares were used on 3%, 13% and 9% of farms in mid Wales, east
Midlands and west Norfolk respectively: snare use was higher on larger farms (over 200
hectares in size), where the use of snares was positively associated with an interest in game
shooting and the employment of a gamekeeper (DEFRA 2005b). Fewer farmers without
game interests culled foxes, irrespective of whether they had livestock (Heydon & Reynolds
2000a). Since a survey of 892 farmers in 1974 by NOP Market Research Ltd found that only
8% used snares (Anon. undated b), there appears to have been little change in the use of
snares on farms over the last 35 years, and that they are of minor importance in reducing
agricultural losses.
In fact, of the farmers surveyed by Heydon & Reynolds (2000a), 82% of farmers in mid
Wales did not cull foxes and 27% said they benefited from the presence of foxes.
Comparable figures for the east Midlands were 40% and 45%, for west Norfolk 58% and
36%. Again, these figures seem to have changed little in the last 35 years: the 1974 survey
by NOP Market Research Ltd found that 49% of farmers in Britain operated no form of fox
control (and a further 11% killed no foxes in the previous year). In Scotland, 79% operated
no form of fox control, the highest proportion in Britain (Anon. undated b). Similar results
were found by Macdonald (1984) in a survey of 84 farmers in the midlands: only 14%
considered the fox to be a major pest, and only 33% considered it a pest at all.
Perhaps the best data on how farmers perceive the need to use snares to control foxes
comes from a survey of 198 "practitioners" undertaken in 2000 (White et al. 2002). Of this
sample of practitioners in England and Wales, 54% were farmers, 12% foresters, 37% fish
farmers and river bailiffs, 4% gamekeepers and 4% nature reserve managers (the
percentages do not sum to 100 since some practitioners fell into more than one category).
For this sample, snaring came 7/11 in terms of use, 6/11 in effectiveness, 9/11 in terms of
acceptability to practitioners and 7/7 in terms of public acceptability i.e. snaring was not
particularly widely used, was not considered particularly effective, and was not considered
to be an acceptable technique.
Snaring mink
A survey of 75 trout farmers in the mid-1980s by MAFF's Wildlife and Storage Biologists
showed that 48% carried out some form of mink control (86% of the farmers who reported
mink on their farm the previous year). Thirty farms used some form of trapping, 7 shooting,
and 3 the local mink hounds: none used snaring (Harrison & Symes 1989).
Most mink control is undertaken over relatively large areas to reduce losses of species of
conservation importance (e.g. Macdonald & Strachan 1999) rather than to reduce
agricultural losses. Mink control relies on trapping, not snaring; mink appear to be
motivated to enter traps by curiosity (DEFRA 2005b). Monitoring and trapping efficiency are
enhanced by setting the traps on rafts. This significantly reduces manpower since these can
be inspected intermittently to see if they have been visited by mink; the traps only need to
be set once tracks or other evidence of mink is found, after which the trap needs to be
checked daily (Reynolds et al. 2004). Whilst an early review of mink control operations
suggested that the available data did not allow any firm conclusions to be drawn on their
effectiveness (Tyler et al. 2005), more recent work has shown that mink trapping can be
effective in reducing mink populations in only 2 to 3 years over relatively large areas with
four months or less trapping per year, but that for small sites (c. 20 km of river) a flexible,
reactive approach is necessary; this needs to be coupled with continual monitoring for mink
presence (Harrington et al. 2009).
Snaring rabbits
Trout (2003) noted that losses to rabbits make many fields in Britain uneconomic other than
from EU subsidy payments, and recommended careful planning of better integrated
management strategies to reduce these losses. Over 30 different methods are used to
control rabbit numbers (Trout 2003), and rabbit control incurs a significant cost. For
instance, in 1994-1995, Forest Enterprise rangers spent 13.3% of their time on rabbit
control: this cost £529,000, including overheads, capital and general equipment costs
incurred by rangers, but excluded specific items such as rabbit fencing (White & Harris
2002). During the period 1995-1998, more than £1 million per annum was spent on rabbit
control by farmers: the average expenditure per farmer on different methods of rabbit
control was £190 on gassing, £100 on shooting, £90 on ferreting, £90 on cage trapping, and
£550 on fencing (Smith 2001). In 2002, total rabbit control in Britain was estimated to cost
around £30 million. This included contract work for gassing and the installation and
maintenance of more than 300 km of fencing at £3.40 per metre. Fencing alone therefore
represented a total cost of £1.02 million (White & Harris 2002).
However, there are few data on the importance of snaring to farmers to control rabbit
numbers. A 1986 survey of around 1000 farmers showed that 72% used day shooting, 48%
ferrets, 27% gassing, 26% night shooting, 5% wire fencing and 5% snaring. In order of
importance, electric fencing, "other", scrub removal, long-netting and spring traps were also
used (Trout 2003). Similar results were obtained in 1998, when the British Association for
Shooting and Conservation surveyed the methods used by 3533 of its members to control
rabbits: the most popular method was day shooting (93% of those who killed rabbits),
followed by night shooting (63%) and ferrets (24%). A small percentage used other methods,
such as netting, snaring, trapping, dogs, gassing and falconry (Reynolds & Harradine 1999).
Whilst this survey will have been biased towards shooters, many of the respondents will
have been land owners and gamekeepers, so it does provide a useful indication of the
importance of snaring to control rabbit numbers.
As we showed at the start, rabbits are often cited by pressure groups as one of the key
species where it is important to continue snaring. However, most professional advice on
rabbit control does not recommend snaring. For instance, Hardy (1990) said that gassing is
the most cost-effective way of controlling rabbits to prevent losses to UK agriculture; he did
not mention snaring. Where a high-value (e.g. vegetable) crop is being damaged, he
recommended live-trapping using a suitable cage-trap and baiting system (Cowan et al.
1989). Hardy (1990) also recommended excluding rabbits from vulnerable crops with either
wire-mesh or electric fencing; properly installed fencing can keep about 80% of rabbits out
of protected fields (McKillop & Wilson 1987; McKillop et al. 1988a). At densities of 20
rabbits per ha, which are common in cereal crops such as wheat or barley, cost recovery for
fencing could be achieved within one or two years. Electric fences were more cost effective
than wire-netting fences in the short term but in the long term there was little difference, so
choice of fencing will depend to a large extent on whether the fence is to be used to protect
crops grown in the same field year after year or to protect crops grown on different fields
each year (McKillop et al. 1988b).
Other experts in minimising economic damage from rabbits come to similar conclusions.
Snaring is not considered to be a particularly effective or humane method of rabbit
management for people growing short rotation willow coppice (Dendy & McKillop 2000).
Similarly, The Forestry Authority recommends fumigation of burrow systems as the most
effective method to prevent rabbit damage to woodlands; cage traps set in fence lines can
also be effective. Although reasonably effective, they do not recommend the use of snares
other than in the rare situations where all other methods have failed (Hodge & Pepper
1998; Pepper 1998). Whilst Natural England says that well-placed snares can catch animals
quickly and efficiently when they are abundant (Anon. undated c), they do not say whether
this actually reduces economic losses.
Snaring brown hares
Most brown hares in agricultural areas are killed by shooting. Most driven hare shoots are
held in February and March, after the end of the game-bird shooting seasons; in the early
1990s around 390,000 were killed in this way (Tapper & Stoate 1992). Up to 80% of the
hares in an area are killed on a driven shoot, so they are a very effective means of reducing
hare numbers locally. In addition some shoots are organised in the autumn, and hares are
also shot at night when lamping and at harvest (Harris & McLaren 1998).
The Forestry Authority recommends fencing or tree guards as the best ways to protect trees
from hares: snaring is not recommended (Hodge & Pepper 1998). Kałuzioski (1976) found
that, even where hare densities were very high in Poland (approximately 50 per km 2),
damage was slight when tree stands were protected, whereas 21% of trees were damaged
in unprotected stands. Whilst Kałuzioski (1976) found no damage to unfenced cherry
orchards in Poland, he added that damage to all types of tree is likely to be more significant
during snowy and severe winters.
As with foxes, the best data on how farmers perceive the need to use snares to control
brown hares comes from a survey of 198 "practitioners" undertaken in 2000 (White et al.
2002). For this sample, snaring came 8/8 in terms of use, 8/8 in effectiveness, 7/7 in terms
of acceptability to practitioners and 7/7 in terms of public acceptability i.e. snaring was not
widely used, was considered the least effective control technique available, and was not
considered acceptable.
Snaring mountain hares
Since mountain hares are listed in Annex V of the Habitats Directive, methods of killing such
as shooting at night with a lamp and snaring may only take place under licence from the
Scottish Government (Newey et al. 2008). However, relatively few licences appear to be
issued: a 2008 review on the conservation and management status of the mountain hare in
Scotland suggested that there were probably less than 30 licence returns on file (Newey et
al. 2008). These were mainly issued to sporting estates to reduce mountain hare
populations to very low densities (< 5 hares per km2) to reduce tick borne disease
transmission or to harvest mountain hares on a sustainable basis. Since many areas selected
for native woodland establishment are juxtaposed with moorland where mountain hare
densities are at their highest, some licences were issued to reduce mountain hare
populations to very low densities to prevent losses of trees (Newey et al. 2008). No licences
have been issued since 2006.
Both mountain and brown hares can be snared at any time of the year since the UK is one of
the few European countries where neither species is afforded a close season (Harris &
McLaren 1998), although the Wildlife and Natural Environment (Scotland) Bill, introduced to
the Scottish Parliament in June 2010, introduces close seasons for both species in Scotland.
There is a closed season on the sale of carcasses (March-July inclusive). This provision, under
the Hares Preservation Act 1892, was originally designed to reduce the number of hares
killed during what was perceived to be the main part of their breeding season, although an
effective close season for both species should run from February 1 to September 30 (Harris
& McLaren 1998), as is the case for most of Europe. Also, with the advent of modern
freezing facilities, carcasses of any hares killed from March to July can be stored for later
sale, making the Hares Preservation Act 1892 largely irrelevant today.
A questionnaire survey of land owners, managers and gamekeepers was used to collate the
numbers of mountain hares killed in 2006-2007; returned questionnaires covered 71,098
km2 i.e. 90% of Scotland. The majority of estates (64% of 291 with mountain hares) did not
kill any in 2006-2007; the remainder killed approximately 25,000 mountain hares under
licence that year, with most being killed by shooting (79%), the remaining 21% by snaring.
Of these, 50% were killed for tick control, 40% for formal/informal shooting and 10% for
forestry or crop protection. Of the hares killed for forestry/crop protection, 1643 (69%)
were shot, 749 (31%) were snared (Patton et al. 2010). Since the pre-breeding population
size for mountain hares in Scotland is believed to be around 350,000 (Harris et al. 1995),
only around 0.2% of the mountain hare population is snared each year for forestry/crop
protection.
Effects on population sizes
There is little evidence that widespread fox culling has any impact on the size of the
breeding population. Hewson (1986) concluded that non-selective fox control in Scotland
during the 1970s was unable to prevent regional population increases. This view was
reinforced by Kolb & Hewson (1980), who concluded that current levels of control were
ineffective at limiting Scottish fox populations. Two studies specifically examined the effects
of killing foxes in winter (when most fox control is undertaken) on the breeding population
the next spring (when most damage is said to occur e.g. Macdonald et al. 2003). Both
studies showed that higher levels of culling in the winter tended to lead to higher
populations in spring, almost certainly due to the numbers of immigrants moving in to
contest the vacant space. Thus fox culling in winter may be ineffective in reducing
population size (Hewson 1986; Baker & Harris 2006), and may be counter-productive.
Similarly, Baker et al. (2002) showed that a cessation of fox hunting during the foot-andmouth outbreak, and limited access to large areas of rural Britain which may also have
restricted the ability of land owners to kill foxes using other means, had no effect on fox
population size.
In contrast, Heydon & Reynolds (2000b) argued that culling can substantially depress fox
numbers. However, this claim has to be viewed with caution since their density estimates
were based on spotlight counts (Heydon et al. 2000). Since these under-estimate fox
numbers (Webbon et al. 2004), it may explain why the density estimates used by Heydon &
Reynolds (2000b) in their calculations (pre-breeding densities, for instance, of 0.41 foxes per
km2, 1.17 foxes per km2 and 0.16 foxes per km2 in mid-Wales, the east Midlands and East
Anglia respectively) were much lower than those reported by other biologists. Lloyd (1980),
for instance, based on an intensive long-term study, estimated fox densities in mid-Wales to
be 1.2 per km2, with 0.5 litters per km2. Webbon et al. (2004) also estimated pre-breeding
fox densities to be higher in all three regions.
Current rabbit population control techniques do not appear to limit population size over
large areas. Rabbit numbers remained low after myxomatosis, but started to recover from
about the mid-1970s, growing at about 2% per annum from the mid-1980s (Trout et al.
1986) despite widespread control measures. Population declines from the mid-1990s
(Battersby & Tracking Mammals Partnership 2005) appear to be due primarily to the impact
of rabbit haemorrhagic disease (RHD) rather than control operations, although these may
have helped keep overall numbers low since control operations are most effective at lower
population densities. Whilst most farmers want many fewer rabbits, few want no rabbits,
recognising the importance of rabbits for sport, food for predators, and their conservation
benefits (Trout 2003). The best way to achieve this balance is carefully planning integrated
rabbit management strategies, using more than one strategy and linking control to the
impacts of disease (Trout 2003).
Of the other three species, mink numbers have declined significantly in Scotland, providing
an ideal opportunity to develop strategies to reduce numbers further to limit their
depredations on species of conservation importance (e.g. Zuberogoitia et al. 2010). Both
mountain and brown hares are BAP species and reducing population size would be counter
to their conservation needs.
Inter-species effects of culling
There is a lot of data to show that population changes of one of the species we have
discussed will have an impact on populations of other species, which in turn will affect
agricultural interests. For instance, Sumption & Flowerdew (1985) showed that reduced
rabbit numbers following myxomatosis led to reduced grazing pressure by rabbits and
denser vegetation growth in a wide range of habitats. This in turn led to high densities of
small mammals in 1956 and 1957; high densities of field voles have significant ecological
impacts. Cadman (1957) reported that the higher vole densities in Wales following
myxomatosis provided an abundant winter food source for foxes, and this enabled the
vixens to produce larger litters of up to 10 cubs in spring. Similar effects have been reported
in Scotland: changes in overwinter mortality were the main cause of fluctuations in fox
numbers, and the most likely factor associated with population fluctuations appeared to be
the availability of field voles as prey during the winter (Kolb & Hewson 1980). In 19th
century, field voles were extremely abundant, reaching very high densities, and periodically
erupted into plagues (Ritchie 1920; Elton 1942). These eruptions devastated agricultural
crops and young trees. One such example occurred in 1891-1893 on the Scottish border:
370 to 470 km2 were infested with voles (Millais 1904-1906). Since then field vole numbers
have declined substantially, in part at least to the reduction in the areas of rough grassland,
and they no longer reach plague proportions (Harris et al. 1995). With lower numbers, the
cumulative impact of avian and mammalian predators appears to play a significant role in
limiting field vole numbers in Britain (Dyczkowski & Yalden 1998; Harris et al. 2000; Baker et
al. 2006). However changes in sward length can lead to increased numbers.
The importance of foxes in controlling rabbits and rodents was recognised by the farming
community long before there was good scientific data to demonstrate the beneficial
impacts of fox predation. For instance, 36% of farmers surveyed in 1974 considered foxes
useful in controlling rabbits and rodents (Anon. undated b). Throughout Britain rabbits form
the major part of the diet of foxes. Baker & Harris (2003) estimated that each fox social
group (taken to be 2.5 adults and 4 cubs) would consume between 190 and 1160 rabbits per
annum in rural landscapes, 91 to 355 in pastoral landscapes, 4 to 387 in marginal uplands,
and 24 to 1067 in upland landscapes. Fox predation can limit the growth of rabbit numbers
when they are already reduced (Trout & Tittensor 1989; Trout et al. 1986). Banks et al.
(1998) demonstrated that, in Australia, fox removal can lead to marked growth in rabbit
numbers, and foxes can limit rabbit abundance in both Australia and Britain (Banks 2000;
Trout et al. 2000). However, Baker & Harris (2003) suggest that rabbit abundance in Britain
is may be higher than can be limited by fox predation. That said, it does not mean that there
are not local benefits to farmers particularly since mild control measures could reduce
rabbit density to that which foxes could regulate.
Foxes also predate brown hares, and locally they can be an important food item (Reynolds &
Tapper 1995). Whilst rising fox numbers in East Anglia since 1970 had no overall impact on
hare numbers (Tapper 1992), fox predation appears to prevent hares reaching extremely
high densities (Reynolds et al. 2010). This is to the benefit of farmers, since very high
densities of hares would lead to significantly increased impacts on agricultural output, as
occurred in the late 1800s prior to the Ground Game Act 1880. As Harris & McLaren (1998)
note, hares can "only be considered a minor agricultural nuisance unless numbers are
excessively high". There are no data on the impact of fox predation on mountain hares in
Scotland, but studies in
Scandinavia showed a significant increase in the numbers of mountain hares shot following
an outbreak of sarcoptic mange in foxes in the 1970s (Lindström et al. 1994; Smedshaug et
al. 1999). Thus fox predation on mountain hares is also likely to be beneficial to Scottish
agriculture.
Discussion
There is a lot of evidence to suggest that the level of fox culling in the UK by farmers is
disproportionately higher than the perceived pest status of foxes (Baker & Macdonald
2000). Whilst it is hard to calculate the costs of fox control in Britain, Heydon & Reynolds
(2000b) estimated that 30% of the UK fox cull was undertaken by gamekeepers, at an
annual employment cost of £55 million. This suggests that the total costs of the national fox
cull in the late 1990s was in the region of £180 million. Obviously, this is a crude estimate,
not least because a significant number of foxes are shot each year for sport (Bucknell 2001),
but this extrapolation gives an indication of the potential cost, and strongly suggests that
the money spent on killing foxes greatly exceeds the total direct agricultural losses to foxes
(£12 million per annum) by around 15-fold. Whilst it has been argued that current levels of
agricultural losses are a reflection of current levels of control, and that losses would be
higher in the absence of control (e.g. Heydon & Reynolds 2000a), it is hard to visualise how
this level of expenditure on fox control is necessary in relation possible agricultural losses to
foxes. This simple comparison also ignores the direct economic benefits of foxes to
agriculture through reducing losses to rabbits and rodents but does help reinforce the
assessment that the number of foxes killed each year, and the money spent in doing this, is
disproportionate to their economic impact. It also suggests that widespread proactive killing
of foxes should be replaced by long-term solutions using non-lethal management
techniques, improved standards of animal husbandry and targeted reactive culling where
losses occur. A combination of such approaches is likely to ensure that any fox problems to
agricultural interests are managed more cheaply and probably more efficiently.
Other analyses have come to very similar conclusions. In a review of predation on livestock
globally, Baker et al. (2008) pointed out that losses experienced by producers are often
highly variable, indicating that factors such as husbandry practices and predator behaviour
may have a significant affect on the relative vulnerability of different farms in the wider
landscape. They also point out that, despite their prevalence of proactive and reactive
culling, the effectiveness, efficiency and cost:benefit ratio of culling programmes have been
poorly studied. Rushton et al. (2006), in a comparison of four different methods of fox
control, concluded that culling at the den was most successful at suppressing fox
populations, but that effective control of populations other than at small spatial scales is not
feasible or practical unless immigration from outside populations is low or can be
controlled. Since foxes can disperse over large distances (e.g. Trewhella et al. 1988),
preventing immigration from areas with lower levels of fox control is not a practical option
in mainland Britain. Immigration is, however, a significant issue for farmers: immigrating
individuals may exert higher levels of predation relative to resident individuals (Althoff &
Gipson 1981; Frank & Woodroffe 2001) and, as we have shown already, culling foxes in
winter can lead to a higher spring population, suggesting that culling foxes may actually
increase losses to farmers. Thus claims that "fox control is vital" to Scottish agriculture do
not stand close scrutiny (Anon. undated a).
Rabbits are a significant problem for Scottish agriculture, although losses today are well
below those that were incurred pre-myxomatosis. Also, since the number of rabbits has
been in long-term decline since the mid-1990s, when rabbits were estimated to be costing
Scottish agriculture around £12 million pounds per annum, it would be reasonable to
assume that the economic losses are also lower. There are a variety of management
techniques that can be used to reduce agricultural losses to rabbits, such as fencing, that
rapidly recoup their costs; snaring is not generally recommended for rabbit control, and
most experts suggest a range of other approaches as being more effective. Since RHD has
significantly reduced rabbit populations, Trout (2003) recommends that this is the time to
develop integrated rabbit management strategies that add to the impact of RHD.
The current debate on the economic impacts on agriculture of a ban on snaring is in large
part a repeat of the arguments of over half a century ago when there were calls for a ban on
the use of gin traps (which came into effect in Scotland in 1974), at a period when rabbits
were far more abundant than today. Sheail (1991) concluded that "The history of pest
control, and the handling of such issues as cruelty, may provide relevant insights into the
more general development of concepts in environmental management during the present
century. The choice of options in wildlife management has always been severely
circumscribed by a lack of understanding of intra- and interspecies relationships and habitat
requirements, and, perhaps at least as significantly, by the constraints imposed by prevailing
social and cultural attitudes towards the stewardship of land and natural resources." Over
half a century later, we are revisiting many of the same issues discussed prior to the making
the use of gin traps illegal, even though there is no evidence that the ban on gin traps in
Scotland had an adverse impact on Scottish agriculture. No one today would call for the
reintroduction of gin traps.
For mink, mountain and brown hares, there is no evidence that they cause significant
economic losses to Scottish agriculture, or that snaring plays any significant role in
addressing any impacts that do arise. In addition, both species of hare are BAP species, and
the conservation aims for both species is to protect and enhance populations. Whilst both
species of hare have some level of legal protection, it is anomalous that, at present in the
UK, neither species has a close season, unlike the situation in most European countries.
Overall, there is no evidence that a ban on snaring would have a significant impact on
Scottish agriculture. The main losses are to rabbits, and other measures are more effective
in reducing their economic impact. Losses to foxes are low, and foxes are, at worst,
economically neutral to Scottish agriculture. Mink, brown hares and mountain hares are
economically of minimal importance to Scottish agriculture.
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