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Introduction and General Information

"There are real or perceived health risks to humans and deer from CWD as well as secondary risks to economic, esthetic, cultural, and environmental values from the effects of the disease or its management." (D146)

In making decisions about programmes to control a disease it is important to identify and assess as far as practical:

  • The costs, direct and indirect, associated with the disease;
  • The costs and the benefits expected from various control strategies. 

In many cases these costs and benefits will have to be estimated, or cannot be put into monetary terms.

It is difficult to estimate either the current or the potential economic implications of CWD. (D143)

Further research is required on the economic, ecological and social impacts of CWD and of CWD management programmes. (D110, D118)

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... to the animal / population

  • For the animal, the risks/costs are those directly associated with the disease in that animal, and the directs effects of different control strategies.

Costs from the disease:

  • CWD is self-sustaining in both farmed and free-living populations of deer and elk. (J1.34.w6, J1.36.w4)
  • The disease causes gradually-developing but eventually severe clinical signs and is invariably fatal. Infection with CWD can be expected to shorten the life span of an animal.
  • There is an unknown impact of CWD on population dynamics of affected populations. (P10.67.w1)
    • Information from outbreaks of the disease in captive facilities, and the results of models of the disease, indicate that eventually the disease could affect and kill high percentages of the population (mortality of up to 100% has been seen in captivity) and could cause extinction of infected populations. . (J40.65.w1)
    • Information available to date suggests that the prevalence in populations will increase, initially slowly, with eventual decimation of the population but long term persistence and spread of CWD due to dispersal and the spatial structure of populations of deer. (J40.65.w1)
  • Models suggest that the disease could substantially harm infected populations of cervids by lowering survival rates for adults and destabilising long-term population dynamics. Quarantine of affected populations limits their usefulness and value. (J64.21.w17)
  • Data from models indicate that CWD could cause significant reductions in local deer populations in affected areas, even population collapse, and that the affected area would be likely to increase in size (e.g. more than ten fold in Wisconsin over ten years. (D109.w5)

Costs from control measures:

  • Depopulation to control CWD will involve culling many animals, including animals which are not clinically affected by CWD and even animals which have never been infected. In the short term, more animals will be killed in depopulation efforts than would be killed by the disease. (D109.w5)
  • Population reduction to control CWD will involve culling many animals, including animals which are not clinically affected by CWD and even animals which have never been infected. In the short term, more animals will be killed in population reduction efforts than would be killed by the disease.
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... to the environment

Costs from the disease:

  • If, as appears possible from some epidemiological models, CWD caused local or larger area extinctions of deer populations, this could have a variety of impacts of the environment. These might be both positive and negative.
  • If perceived human health risks cause a cessation or dramatic decrease in hunting by the public in certain areas this could result in excessive growth of deer populations and resultant adverse effects on wildlife habitats. (D124)

Costs from control measures:

  • Depopulation and herd reduction, where undertaken in management efforts, could have a variety of impacts on the environment which could be positive as well as negative.

The following discussion of possible environmental effects of disease control measures, based on a consideration of the situation in Wisconsin, is taken directly from D109 - Environmental Impact Statement On Rules to Eradicate Chronic Wasting Disease from Wisconsin's Free-Ranging White-tailed Deer Herd: Depopulation. Similar effects, to a lesser degree, would be expected from heard reduction measures.

Ecological effects. The specific ecological effects of reduced deer population size in an EZ Prion gene sequence analysis of CWD-positive and CWD-negative Odocoileus virginianus - White-tailed deer from Wisconsin’s current EZ [Eradication Zone] would vary depending on the location of the zone. Currently, the EZ defined by the 2002 emergency rule covers a 411 square mile area in southwestern Wisconsin. If CWD is confined to southwestern Wisconsin, the ecological effects of deer depopulation would be more limited than if a much larger EZ is defined in response to the discovery of CWD in other regions of the state. Few studies have directly measured deer density and its effects on the entire ecosystem. Short and longterm ecosystem effects are situation-specific, but documented negative effects of deer on ecosystems are virtually always a function of overabundance (reviews in VanderZouwen and Warnke 1995, Waller and Alverson 1997, McShea et al. 1997). The recent Environmental Assessment done to evaluate effects of altering deer management unit boundaries and population goals (VanderZouwen and Warnke 1995) contains an exhaustive review of the scientific literature on deer density effects on ecosystems at that time. The following paragraphs are summaries of that effort for discrete ecosystem components. Literature citations are not repeated here but can be found in the Environmental Assessment, which can be obtained by contacting the DNR through their website at http://www.dnr.state.wi.us.

Herbaceous Vegetation. Reducing the deer herd to zero could have an effect on herbaceous plants. Deer eat a wide variety of herbaceous plants during the growing season (species from 70 genera and/or families in the north and 53 in the south). Characteristics of herbaceous plant species that could benefit by very low deer populations include rare species, species found in restricted habitats, short-lived species, species that produce only single stems, and species highly preferred by deer. Species that are common and well distributed are unlikely to be greatly affected unless they are highly selected by deer. Prairie forbs selected by deer tend to have a relatively low abundance compared to the other more abundant prairie species; therefore, lower deer populations could have a significant benefit on the reproductive output of these species. Forest species that could benefit are bluebead lily and Canada mayflower. In southern fragmented woodlands, large-leaved trillium could benefit at deer densities less than 15 deer per square mile. The literature provides few deer density estimates when impacts become significant for a given species. Although there are few data to base judgments on what deer densities affect herbaceous vegetation, deer densities at low levels may likely benefit some rare species, some forbs in native prairies, some spring ephemeral in southern woodlands, and some forest floor species in the north, especially those found in restricted habitats.

Woody Vegetation. Since deer browse woody vegetation during winter, regeneration, abundance, and vigor of trees and shrubs could benefit from reduced deer numbers. Information is inadequate to scientifically determine the overall impacts of deer densities on the vegetation in the state. There have been studies documenting extreme high levels of deer herbivory but few carefully designed studies assessing the effects of different deer densities on vegetation. Generally, the published literature reports moderately heavy browse impacts occur to the most preferred trees and shrubs at deer densities of 20 per square mile. Heavy impacts were noted in many states at greater than 25 deer per square mile. These studies were conducted in regions of the country where forests have higher productivity (carrying capacity) than Wisconsin. Based on these studies and productivity of Wisconsin forests, moderately heavy browse impacts could occur at 15-20 deer per square mile and heavy browse impacts could occur at more than 20 deer per square mile in Wisconsin. These preferred tree and shrub species could benefit from lower deer numbers. Impacts by deer on woody vegetation in northern Wisconsin during winter can be significant if deer are concentrated within an area for thermal cover and mobility during times of deep snow. Preferred conifers sensitive to browsing ( e.g., white cedar, hemlock, Canada yew, and white pine under some conditions) may benefit at low deer densities in these local wintering areas. The overall extent of this impact is unknown and would depend on how much and how often deer are concentrated. At low deer densities in the north, preferred deciduous trees sensitive to browsing ( e.g., yellow birch, basswood, oaks, and white ash) and shrubs may also benefit. Oak species and other preferred shrub species in the southern regions might benefit from low deer population densities. Deer impact on conifers in summer is negligible since they seldom use them in that season. Impacts on deciduous trees and shrubs by browsing leaves and new shoots can be substantial. Lower deer levels concentrating in the northern region around a summer food source ( e.g., regenerating clearcut or forest opening) could benefit preferred deciduous species that are sensitive to browsing (yellow birch, basswood, and white ash). In southern regions, lower deer densities could benefit preferred species such as the oaks, basswood, and white ash.

Invertebrates. Some species could benefit from lower deer densities by indirect effects on vegetation. There are no data suggesting how invertebrates are affected by different deer densities. Inference from knowledge about invertebrates would suggest that the increase of a plant species that supports a hostspecific invertebrate population, due to reduced deer browsing, would cause that invertebrate population to increase. Some invertebrates would benefit more than others because of reduced deer herbivory. Invertebrates requiring a single plant species to complete its life cycle would likely benefit from lower deer numbers. Invertebrate species that use only the flowering part of one plant to complete its life cycle that is highly preferred by deer would benefit even more from lower deer numbers. A detailed analysis of the impacts of deer browsing on invertebrates and host-specific plants needed to complete their life cycle is needed to understand the effects of deer herbivory on invertebrates. It is possible that a reduced deer herd could result in fewer deer ticks and a possible reduction in cases of Lyme disease and Erhlichiosis. 

Herptiles (reptiles and amphibians) . Reduced deer numbers could indirectly benefit or harm herptile species. There are no data on deer effects on herptiles. Indirect effects by deer changing habitats are the only way to assess deer impacts on herptiles at this time. Deer could modify the habitat structure needed by specific herptiles or change the food base (invertebrates) for herptile species. Thirty-eight herptiles (14 rare) occur in the same habitats as deer and could potentially be affected by deer herbivory. Although no data exists for analysis, the following suggestions are inferred from what is known about herptiles and their habitats. All of the state’s insectivorous herptiles are believed to be generalists, and it is unlikely deer are causing a general decline in invertebrate biomass and reducing the food base for herptiles. It is more likely that deer could alter habitats and indirectly affect herptiles. Of the 14 rare herptile species, five need open habitats ( i.e. wood turtle, Blanding’s turtle, ornate box turtle, western worm snake, and prairie ringneck snake) and are suffering from advancing woody plant species succession. Reduced deer densities and browsing might harm these herptile species by reducing more open habitat. Four herptile species need moderate levels of brush and open habitats (western slender glass lizard, bull snake, eastern massasauga rattlesnake, and timber rattlesnake). These species could be positively or negatively affected depending on the intensity of browsing. The remaining five rare herptiles would be unaffected by deer density (four-toed salamander, northern ringneck snake, black rat snake, Butller’s garter snake, and the western ribbon snake). The density of deer needed to bring about these habitat changes is unknown. 

Small mammals. No direct relationship between deer and small mammals was found. Deer, however, may impact small mammals by altering their habitat ( e.g., litter layer) and food base ( e.g., seeds) by changing plant composition. Reduced deer densities could therefore benefit or harm certain small mammal species depending on the species' habitat needs.

Birds. Bird species could indirectly benefit or be harmed by changes in vegetation caused by deer foraging. Three studies discuss impacts of differing deer densities on birds in the eastern United States. Ground and canopy nesting birds do not seem to be greatly affected by deer browsing. Shrub nesting species were most impacted by deer browsing if the shrub layer is reduced. Bird species least likely to be affected by deer browsing in are ground or canopy nesting species. However, long-term impacts on forest species composition by deer browsing (shift toward conifers in canopy) could benefit canopy-nesting birds preferring conifers ( e.g., hemlock and white cedar) in northern Wisconsin. Deer densities in northern Wisconsin are close to the level where negative impacts on shrub nesting birds were documented in other states. It is unclear where significant impacts of deer browsing on birds begin, but it is believed to be between 15-30 deer per square mile. When deer densities reached 35 deer per square mile there were documented negative impacts on some bird species in the eastern U.S. These studies were conducted in regions of the country where forests have higher productivity (carrying capacity) than Wisconsin. For forests in Wisconsin, lower deer densities than those reported above could affect bird species. In the northern region, species like black-throated blue warblers, Canada warblers, and Swainson’s thrush would likely benefit from lower deer densities. If the developing canopy does include conifers, then species like blackburnian warbler, golden-crowned kinglet, and northern parula may benefit in the future. Some deer densities in the south are at or very close to the deer densities that significantly impacted birds in eastern studies. Species that may benefit most from lower deer densities in southern Wisconsin are chestnut-sided warblers, worm eating warblers, mourning warbler, Kentucky warbler, and hooded warbler. The wood thrush might also benefit because it nests primarily in shrubs or saplings in Wisconsin. Other species that might be affected by less deer browsing in southern Wisconsin are the veery and white-eyed, Bell’s, and red-eyed vireos. It is not expected that lower deer densities would have a significant impact on turkey densities.

Moose and Elk. Both populations of moose and elk are extremely small in Wisconsin at this point in time. Interspecific competition between elk, moose, and deer does not seem likely except in severe winters when both elk and deer may occupy conifer yards. Due to the extremely small populations of moose and elk in Wisconsin, competition among these three species seems insignificant. Deer act as a reservoir for the parasite Parelaphostrongylus tenuis. Mortality does occur from P. tenuis in elk but at levels too low to affect robust elk populations. Moose are extremely susceptible to P. tenuis and are not likely to persist if deer populations are above 15 per square mile; however, 90% of low deer density habitat surveyed in Wisconsin was judged as not suitable for moose. Moose and elk are likely to benefit from reduced deer density in northern Wisconsin. 

Wisconsin has one wild elk herd that is located near Clam Lake in the northwestern part of the state. This herd was established in 1995 when 25 animals were transplanted from Michigan. The population has grown to an estimated 120 animals during the past seven years. The Natural Resources Board (NRB) has approved establishment of a second wild elk herd in Jackson County. This project is currently on hold to await completion of CWD surveillance within the central forest region. In addition, the NRB gave their approval contingent that elk be added to the wildlife damage program, which is dependent upon DNR promulgation of rules to establish an elk hunting season. The Jackson County introduction would need to meet all applicable regulations regarding the importation of cervids into Wisconsin, as well as all health testing and monitoring requirements.

Because elk are susceptible to CWD, the presence of CWD in Wisconsin poses a threat to their restoration in the state. Both the existing Clam Lake elk population and the proposed Jackson County population are outside of the CWD eradication and management zones. Failure to control CWD in the current EZ, however, could result in its spread throughout Wisconsin’s deer herd, which would threaten the proposed Jackson County elk population and eventually could threaten the Clam Lake herd. 

Large Carnivores or Scavengers. The gray wolf is the only large carnivore species that depends heavily on deer as a food source in Wisconsin. The Wisconsin DNR reclassified wolves from endangered to threatened in 1999, and the U. S. Fish and Wildlife Service started the process to reclassify them in 2000, and should complete the process in 2003. Deer are the primary food source for wolves in Wisconsin.Currently, the CWD management zones are in Wolf Management Zone 4. This zone includes 28 counties in southern and eastern Wisconsin that appear to have limited potential for wolves. Currently, no wolf packs are known to occur in this zone and no wolf depredations have occurred in the zone (Wydeven and Wiedenhoeft 2002). During July 2001-June 2002 wolf observations were reported from seven counties in the zone but these may include misidentifications. An adult male wolf was killed by a vehicle on the westside of Madison in April 2002; however the presence of this wolf is not likely indicative of a resident population. Because the areas currently included in the CWD EZs and IHZs [Intensive Harvest Zones] are outside of the northern and central forest wolf range, the proposed deer population reductions are not expected to have an impact on the recovery of Wisconsin’s wolf population. If new EZs were established in the northern wolf range, it is unlikely that deer depopulation would have population-level effects on wolves given the unprecedented high deer populations in northern Wisconsin (Wisconsin DNR 2001) unless CWD was found to be widely distributed in the north. 

Several other carnivore and omnivore species - black bear, coyote, and bobcat - prey on deer fawns when available. In addition, several species of birds use road-killed deer as a source of carrion - common raven, American crow, turkey vulture, and the bald eagle - are among these. These predator/carrion species are generalists and would not be expected to be greatly affected by changing deer densities.

Ecological Function and Productivity. Deer may have indirect impacts on other taxa within the ecosystem ( e.g., birds, small mammals, herptiles, invertebrates, etc.) or on ecological function or productivity due to their effect on vegetation. Direct impacts to ecological function and productivity by deer seems unlikely because vertebrates contribute very little directly to nutrient cycling and energy flux. However, deer browsing might alter the composition and structure of vegetation used by species in other taxa as habitat. Negative effects on native ecosystems associated with too few white-tailed deer have not been described or demonstrated in the scientific literature.

The depopulation proposed for a CWD EZ and IHZ would likely reduce many of the adverse ecological impacts that high deer densities in Wisconsin may have caused during recent years. If a large proportion of hunters decide not to hunt in the future because of human health concerns, deer harvests in the region may actually decline resulting in further growth of the deer population and subsequent greater adverse impacts on regional plant communities and dependent animal species. Eventually, an infected population would collapse from CWD and impacts from deer on the ecosystem would be lessened.

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... to wildlife management agencies

Costs from the disease:

  • If established within the game farm industry there could be a risk of transmission from game farm animals to free-ranging cervids. (J64.11.w3)
  • Operational budgets of state and federal wildlife management agencies are supported by sale of hunting licences; public health concerns regarding the presence of the disease in wild cervid populations may lead to decreased sales of hunting licences and therefore decreased income for wildlife management agencies. (D124, D143)

Costs from control measures:

  • Deer and elk cannot be translocated from CWD endemic areas. (P10.67.w1)
  • Ongoing surveillance programs are expensive; this takes resources away from other wildlife management needs. (B209.17.w17, P10.67.w1, J64.21.w17)
    • Surveillance costs include costs of live-trapping cervids where appropriate, collection of samples, processing of samples, entry of surveillance results into a database, communication of results.
  • Costs of control measures, including research and provision of information, may be considerable and may exceed normal budgets for responsible wildlife management agencies. (D114.VII.w7)
    • Costs associated with culling e.g. use of sharpshooters to cull deer in herd reduction or herd eradication zones.
    • Culling, by reducing populations, may reduce the number of hunting permits available and thereby reduce income to state agencies. (V.w48)
    • Costs associated with carcass disposal e.g. costs associated with storage of carcasses pending test results and safe disposal of CWD-positive carcasses and carcasses of unknown CWD-status.
    • Costs associated with education and provision of information - production and distribution of brochures on CWD, writing of articles, taking part in local media interviews, holding public meetings etc.
    • Costs associated with research into the disease.
  • Changes in deer herd monitoring procedures would be needed in areas of depopulation; aerial surveys using fixed-wing aircraft or helicopters may be required. (D109.w5)
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... to deer/elk farmers

For the farmer, direct and indirect risks/costs are associated both with the disease in his stock, and with different control strategies.

Costs from the disease: 

  • This disease presents a health threat to captive herds. (D143)
  • If allowed to reach high prevalence, losses of animals due to the disease could be significant, as has been seen in captive wildlife research facilities. (J64.11.w3)
  • There may be costs of treating animals showing clinical signs of disease, but in which a clinical diagnosis of CWD has not yet been made.
  • In scrapie-affected sheep flocks it has been noted that "financial losses arise from several sources: direct loss due to death from scrapie or unnecessary culling, impaired rearing of lambs which have affected mothers, large indirect effects due to loss of reputation by individual breeders or the wider repercussions in the disruption of the world sheep trade and, last, the damage to genetic improvement schemes where 'avoidance of scrapie' can be a precondition limiting the choice and therefore the selection potential." (B298.10.w10)
  • If spillover of the disease occurs from captive to wild cervid populations, with establishment of new endemic foci, this could impair the viability of cervid farming in such areas long-term. (J64.21.w17)
  • Consumer perceptions about the safety of venison could impact demand for cervid products such as venison, whether this perception was because of or despite scientific evidence on safety. (D143)

Costs from control measures:

  • In the game farming industry there could be a large economic impact. (J64.11.w3)
  • Captive populations are quarantined if found to be CWD-positive, which limits the use and value of infected or exposed animals.(B209.17.w17, P10.67.w1, J64.21.w17)
  • Restrictions by individual states on import of cervids from other states may significantly impact the cervid breeding stock market. (D143)
  • Costs from restricted use of land considered to be contaminated with CWD could be considerable. 
    • In Saskatchewan, four farms where CWD had been detected were banned from keeping any livestock or growing grain. (W27.15Jan03.cdw1)
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... to wildlife research facilities

Costs from the disease:
  • Excessive mortality of young adult cervids from CWD reduces the number available for basic research (on e.g. nutrition, reproduction, behaviour and diseases).
  • Effects of disease can have an impact on the results of research.
  • Requirement for replacement of individual hand-reared animals suitable for research, in which there has been a considerable investment. 
  • Costs of treating animals showing clinical signs of disease, but in which a clinical diagnosis of CWD has not yet been made.

(P42.12.w1, J64.11.w3)

Costs from control measures:

  • Quarantine of affected populations limits their usefulness and value.
    • Reduced options for management of surplus animals (which cannot be exported from an affected facility)
    • Reduced possibility of exchange of animals between facilities. 
(B209.17.w17, P42.12.w1, J64.11.w3, J64.21.w17)
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... to deer and elk hunters

Costs from the disease:
  • Hunting is valued by hunters in recreational terms and as a source of meat. The value as a source of meat may be decreased by concerns regarding possible human health implications of CWD. (D143)
    • Data from a survey of gun deer hunters in Wisconsin indicated that the perception of health risk by hunters associated with CWD was lower than that of being shot by a hunter from another party and no higher than that of contracting Lyme's disease, although higher than that of being shot by a member of their own hunting party, falling from a tree stand, having an automobile collision while travelling to or from their hunting location, giving themselves a knife wound while gutting their deer or shooting themselves. (D145)
    • Data from a survey of gun deer hunters in Wisconsin indicated that, of those who had not hunted during 2002, for 25% the reason was because they (22%) or their partner (3%) had concerns about CWD and the safety of venison and for a further 7% "I do not believe in hunting only for killing - where I can't eat the meat." (D145)
    • Data from a survey of gun deer hunters in Wisconsin indicated that most hunters were likely to continue hunting unless CWD reaches epidemic proportions but in such circumstances they would begin to abandon hunting. (D145)
  • Cost of having harvested animals tested for CWD (where not paid for as part of surveillance efforts) due to public health concerns.
  • Data from models suggests that in the long term, if not managed, CWD could lead to substantial population reductions and even local extinctions of infected populations (J40.65.w1, J40.66.w1, J64.21.w17). This would lead to a loss of hunting opportunities.

Costs from control measures:

  • Possible increase in effort required, particularly for bow hunters, where baiting is prohibited as a disease control measure. (W400.13Apr03.CWD4, D109.w7,  D109.w17)
  • In endemic areas there may be conflicts between disease management aimed at ensuring the long-term health and viability of cervid populations and opportunities for recreational hunting. (D126)
    • Data from a survey of gun deer hunters in Wisconsin indicated that, of those who had not hunted during 2002, 1% did not hunt because "There aren't enough deer where I traditionally hunt." (D145)
    • Data from a survey of gun deer hunters in Wisconsin indicated that, of those who had not hunted during 2002, 1% did not hunt because "I hunt with bait and baiting is now illegal." (D145)
  • In areas where populations are being greatly reduced for disease management purposes there may be a long-term (several years) reduction of hunting opportunity.
  • During the herd reduction/depopulation efforts there may be increased hunting opportunities, however hunters may be asked to harvest more deer than they can use and to assist with the elimination of the animal which they traditionally hunt; this could be problematic for hunters. (D109.w5)
    • For hunters who strongly disagree with such policies there may be a need to hunt in a different location.
    • Data from a survey of gun deer hunters in Wisconsin indicated that, of those who had not hunted during 2002, 4% did not hunt because "I disagree with the [Wisconsin] DNR management approach to CWD and did not hunt as a personal protest." (D145)
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... to other wildlife-related recreation

Costs from the disease:

  • "It is reasonable to assume that, like hunting, CWD could adversely affect the recreational benefits of those who enjoy wildlife viewing." (D143)
  • Data from models suggests that in the long term, if not managed, CWD could lead to substantial population reductions and even local extinctions of infected populations. This would reduce opportunities for watching of cervids.

Costs from control measures:

  • From increased culling: Potentially there are recreational conflicts if hunting regulations are changed to increase culling of deer for the management of CWD. (D109.w5)
    • Hikers, cyclists and skiers may be concerned about their own safety during extended deer hunting seasons and may therefore choose not to undertake their normal recreational activities.
    • Hunters of other species (e.g. turkey, waterfowl) may be concerned about their own safety and the safety of their dog, if they normally hunt with a dog.
  • From restrictions on Feeding and Baiting: Restrictions on feeding deer may reduce the opportunity for deer watching. However in Wisconsin it was noted that while such a ban would be likely to reduce opportunities to view deer near to homes and businesses it might also put a higher value "on seeing those deer that remain." (D109.w7)
  • From depopulation/herd reduction: Opportunities for wildlife (deer) viewing would be reduced if the deer population was reduced. (D109.w5)
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... to the related trades / professions

Costs from the disease:

  • Deer hunters spend money on hunting gear and on hunting trips. (D143)
  • If deer hunters concerned about CWD choose not to hunt, or not to hunt in a particular area, this would be expected to reduce the income of businesses which normally sell hunting supplies, gasoline etc. to hunters in those areas.
    • To some extent this may be offset against money, which would normally be spent on deer hunting, being spent on other activities.

    (D144)

  • Data from models suggests that in the long term, if not managed, CWD could lead to substantial population reductions and even local extinctions of infected populations (J40.65.w1). This would be expected to reduce the income for all trades/businesses with an income related to deer hunting or deer watching.

Costs from control measures:

  • From increased culling: 
    • In areas where populations are being greatly reduced for disease management purposes there may be a long-term (several years) reduction of hunting opportunity. This would result in reduced income for some businesses associated with hunting. (D109.w5)
  • From restrictions on Feeding and Baiting:
    • Businesses selling feed and bait would have a reduced income in areas where baiting and feeding of deer and elk was restricted or forbidden. (D109.w7)
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... to Tribal communities

Costs from the disease:
  • It is impossible to state definitively that CWD cannot cause disease in humans. In order to reduce the risk of transmission of the disease to humans, traditional activities such as the use of deer brains to tan hides may be affected.

Costs from control measures:

  • Depopulation or herd reduction, if required for CWD management in the ceded territories, might impact overall tribal deer harvest, tribal customs, availability of venison and recreational opportunities. (D109.w5, D109.w6)
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... to the consumer: meat and other animal products

Costs from the disease:
  • At this time there is no evidence that CWD has been transmitted to humans, however this is a relatively "new" TSE and it is not possible to say definitively that CWD cannot be transmitted to humans. It is probable that relatively few people have, to date, eaten meat products from CWD-affected cervids, and it is likely that the incubation period would be long. It is also not yet possible to say definitively that CWD cannot be transmitted to cattle or sheep and that, if such transmission is possible, the agent might be changed on passage through the other species so that infection of humans is possible. 
  • In December 1999, the World Health Organization stated, “There is currently no evidence that CWD in cervidae (deer and elk) is transmitted to humans.” They further state, “...no part or product of any animal with evidence of CWD or other TSEs should be fed to any species (human, domestic or captive.)” (W425.27Mar03.CWD5)
  • The TSEs have long incubation periods and relatively few humans are likely to have eaten meat or other products from CWD-infected cervids. It is probable that, if CWD is transmissible to humans, it is too early to expect to have detected any cases.
  • PrPres has been detected in the tongue muscles of hamsters and in skeletal muscles of mice experimentally infected with TSE diseases. These findings indicate that, if CWD is transmissible to humans, there might be a risk, however slight, from people eating muscle tissue (meat) from infected animals. (J80.77.w1, J135.99.w2)

Costs from control measures:

  • It is possible that control strategies put into place to minimise potential risks to human health may decrease the availability of some deer or elk products such as venison and products containing antler velvet.
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... to landowners

Costs from the disease: 
  • If hunters choose not to hunt due to perceived human health risks this could result in decreased revenues to landowners who normally gain income from deer leases. (D124)
  • Land values may decrease, for areas of private land valued for hunting, if the demand for hunting falls due to concerns regarding the disease or due to decreased quality of hunting. (D143)
  • Land values may be affected if CWD were discovered to be transmissible to livestock or humans. (D143)

Costs from control measures:

  • Where depopulation is carried out this might have a negative or a positive impact on property values depending on "the type of land, land use and the motivation of the parties concerned." (D109.w5)
  • Agricultural crop damage from deer would be expected to be greatly reduced in areas where herd reduction or in particular depopulation was carried out; this effect would last until after the area was repopulated by deer. (D109.w5, D109.w6)
  • Damage to industrial forests would be expected to be greatly reduced in areas where herd reduction or in particular depopulation was carried out; this effect would last until after the area was repopulated by deer. (D109.w5, D109.w6)
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... to the CWD affected region

Costs from the disease: 
  • In terms of economics, one estimate for Wisconsin suggested that there would be a reduction in hunting in 2002 of 10-20%. 
    • Using known data for average spend per hunter, it was estimated that $48-$96 million less would be spent by deer hunters on deer hunting. 
    • However it was also considered that more than 90% of the hunters who would choose not to hunt would be Wisconsin residents, who would be likely to spend the money saved by not hunting within Wisconsin. This resulted in an estimated $5-$10 million loss from out-of-state hunters. 
    • It was noted however that the loss would be felt most by businesses and households within the hunting economy, such as "motels, eating and drinking establishments, deer processing facilities, and gas stations where hunters from urban areas spend money locally."
    (D144)

Costs from control measures:

  • From depopulation / herd reduction:
    • It is likely that the number of deer-vehicle collisions, which are a significant problem in areas such as Wisconsin, would be reduced in line with the reduction in population. (D109.w5, D109.w6)
    • It is likely that damage to agricultural crops from deer would be decreased while the number of deer was reduced. (D109.w5, D109.w6)
Associated techniques linked from Wildpro
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... to the CWD affected country as a whole

Costs from the disease: 
  • Potentially, this disease could have a detrimental effect on the national herd of deer and elk - reducing the overall health status and the numbers of animals.

Costs from control measures:

  • Animal health regulations have been established by the USDA Animal and Plant Health Inspection Service approving payment of indemnity for voluntary depopulation of infected captive cervid herds (9 CFR Part 55) to encourage participation of producers in the disease eradication programme. There are considerable Federal costs associated with payment of indemnity for depopulation of infected captive herds of cervids; payment is made of 95% of the appraised value of the animals up to $3,000 per animal. (D143)
  • There is the possibility that trade sanctions may be imposed to prevent export of CWD. (D143)
Associated techniques linked from Wildpro
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Authors & Referees

Authors Dr Debra Bourne MA VetMB PhD MRCVS (V.w5)
Referee Suzanne I Boardman BVMS MRCVS (V.w6), Chris Brand (V.w52), Dr Terry Kreeger (V.w49), Dr Julie Langenberg (V.w50), Bruce Morrison (V.w48), Michael Samuel (V.w53), Scott Wright (V.w54)

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