RELATIONSHIPS AMONG MULE DEER AND THEIR PREDATORS Fact Sheet #1

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1 RELATIONSHIPS AMONG MULE DEER AND THEIR PREDATORS OVERVIEW Relationships between predator and prey abundance are complex and not easily described. Under certain conditions, predators may influence fluctuations in mule deer populations and affect the goals that managers set for a specific population. Only by understanding the complexity of predator and prey relationships will it be possible to determine if or when management of predators will be effective in helping mule deer populations. BACKGROUND Mule deer are prey for many large predators of western North America. In the western U.S. and Canada, those predators are primarily mountain lions, coyotes, and bobcats, although black bears, wolves, grizzly bears, and feral dogs will also take mule deer. Predators can have a limiting or regulating effect on mule deer populations. However, many factors interact to influence mule deer abundance, and predation is only one part of the equation. Predator control is simply the removal of predators. Predation management is any activity that may influence the relationship between predators and their prey, including habitat enhancement to increase prey security and lethal removal of predators. In most cases, reducing the number of predators to increase mule deer populations is inefficient and cost prohibitive. Therefore, predator control should only be instituted when circumstances indicate a high likelihood of management success, and where specific and measurable objectives can be applied and carefully monitored. THE INFLUENCE OF PREDATORS The influence of predators on mule deer populations is variable and based on several factors that include: 1) Relationship of the mule deer population to the carrying capacity of the habitat, 2) Overall habitat condition, 3) Abundance and distribution of alternate prey populations, and 4) Number, abundance, and distribution of predator species that inhabit mule deer range. When mule deer populations are close to carrying capacity, predation tends to have less influence on the population, and reductions in predator numbers are unlikely to result in an increase in the mule deer population. When habitat conditions are favorable, mule deer have better nutrition and more cover, which reduce susceptibility to predation. Likewise, winter habitats with deep snow can limit mobility and increase vulnerability to predation. When alternate prey species occupy the same habitats as mule deer, predator populations have more prey from which to select. In those instances when mule deer numbers decline, predators may switch to other prey, thereby reducing effects of predation on remaining mule deer. Conversely, this ability to switch prey may maintain stable or high predator numbers, which can in turn limit mule deer population growth when below their carrying capacity. In mule deer range with multiple predators, those predators may compete with one another, which may influence predator abundance (e.g., increased coyote numbers may result in decreased bobcat numbers). In short, the relationships between predator and prey are complex, difficult to isolate and characterize, and rarely result in simple management solutions. AZGFD - George Andrejko

2 Kim Morton Society places varying values on predators and the role that they play in an ecological setting. Wildlife management agencies typically develop outreach plans that include media releases, public meetings, and educational campaigns to help people understand not only predator-prey relationships, but also differing views about predator-management programs. A common misperception among hunters is that simply removing some predators will lead to increased mule deer numbers. In practice, predator removal to benefit mule deer populations is only effective under a few specific conditions. USING SCIENCE TO GUIDE MANAGEMENT In reviewing scientific research on predator control, there were similarities in cases where predator control was effective at improving deer populations. In general, predator control has been effective when: 1) Predation was identified as a limiting factor, 2) Predator control was implemented when deer populations were below habitat carrying capacity, 3) Control efforts reduced predator populations sufficiently across the landscape to yield results (e.g., expected to be about 70% of a local coyote population), 4) Control efforts were timed to be most effective (just prior to predator or prey reproduction), 5) Control occurred at a focused scale (generally <250 mi 2 ). Many factors must be considered prior to implementing a predation management program, including: 1) Development of a management plan that identifies: a. Current status of mule deer populations relative to carrying capacity, b. Factors that may be playing a role in reducing mule deer populations, c. Deer population objectives desired through predation management, d. Desired population reduction goals for the predator species, e. Scale of the predator control effort, f. Timing, method, and budget for predation management efforts, g. Public outreach plan. 2) An adaptive-management plan should include how predator and prey populations will be monitored to determine when goals have been achieved or how management programs can be adjusted. More information on mule deer can be found at Ballard, W. B., D. Lutz, T. W. Keegan, L. H. Carpenter, and J. C. devos, Jr Deer-predator relationships: a review of recent North American studies with an emphasis on mule and black-tailed deer. Wildlife Society Bulletin 29: A product of the Mule Deer Working Group - Sponsored by the Western Association of Fish & Wildlife Agencies - Approved July 2013 Produced with support from the Mule Deer Foundation (

3 UNDERSTANDING MULE DEER AND WINTER FEEDING Fact Sheet #2 Starvation of wild animals is part of nature. Virtually all wild animal populations experience significant and dramatic population fluctuations. Human compassion makes people want to help mule deer with winter-feeding programs. Changing nature by winter feeding is a complex matter involving numerous issues to be considered before determining a course of action. BACKGROUND - Supplemental winter-feeding programs, despite broad social appeal and acceptance, are expensive, can negatively affect mule deer behavior and biology, and save very few deer. Inadequate habitat and severe winter weather with heavy snow accumulation and cold temperatures are the ultimate cause of most winter-feeding programs. Prior to initiating winter feeding, the potential for long-term benefits to mule deer as well as habitat conditions needs to be critically evaluated. BIOLOGY - Several unique aspects of mule deer biology complicate the potential for successful winter feeding. Unlike elk, mule deer are highly selective foragers, at least in part, due to their specialized digestive system. As ruminants, mule deer rely on a very complex stomach system to aid in digestion. Mule deer use bacteria in their rumen to aid in the digestion of their food. Specific types of bacteria are required for specific types of food, therefore the type of food required for winter feeding of mule deer is highly limited, very specific, and must be properly formulated. Because the digestive system can t adapt quickly enough, supplementally fed mule deer may die with full stomachs. This is especially the situation when starving mule deer are fed alfalfa hay, corn, or other traditional livestock feeds. BEHAVIOR - Mule deer behavior may also be negatively affected by winter-feeding efforts. Behaviors important to mule deer survival include learned behaviors, such as foraging and migratory habits; both critical to the long-term sustainability of a population. Winter-feeding has the potential to disrupt both winter foraging activities and migratory patterns. As mule deer learn locations of feeding stations, they continue to visit these sites, sharing this information with each successive year s offspring. As each generation becomes more reliant on artificial food sources, they become less familiar with natural foraging sites and activities. Additionally, mule deer may fail to recognize the need for migration. DISEASE AND PREDATORS - Winter-feeding programs generate artificially high animal densities at feeding sites. These high densities of animals provide ideal opportunities for the transmission of diseases and parasites. Winter feeding in areas highly populated by humans may create significant liability issues in terms of attracting predatory animals such as mountain lions and domestic dogs. COMPETITION - Mule deer compete fiercely for food when it is limited. Consequently, the biggest, strongest, healthiest deer, such as dominant does, exclude the truly needy individuals (usually fawns) from the food. By placing a resource in a localized area, competition is increased and some deer get little or no food, while others gorge themselves and get too much. Too much of a supposed good thing can also jeopardize their survival due to complications from dietary shock.

4 UNDERSTANDING MULE DEER AND WINTER FEEDING SOCIOLOGY - Sitting by and watching mule deer die from starvation is not something most of us are willing to do. Both proponents and opponents of winter feeding believe they have the deer s best interest in mind. However, even well designed and executed winter-feeding programs often fail to significantly increase the chance of mule deer survival. Even if winter feeding could save a few deer from starvation, we must consider the biological cost to the habitat, cost to other species, and cost to mule deer in the long term. We must focus on the sustainability of the mule deer population for generations to come not just one season. Another problem resulting from the initiation of feeding by private citizens is the desire to continue feeding at times of the year mule deer don t need it but will choose to stay on it, further complicating the concerns outlined above and often providing food sources that may ultimately kill deer. Uncoordinated or casual feeding efforts result in dozens of different foods being fed, while deer migratory habits, foraging behavior, and fear of humans are also negatively affected. Feeding can attract deer into landscaped yards and high traffic areas, causing damage to gardens and increasing vehicle accidents. People who feed deer often ignore the real issue of availability and condition of natural habitats. They believe supplemental feeding, can adequately meet mule deer nutritional needs. CONCLUSIONS - Government agencies in western North America have conducted supplemental feeding of wildlife for about 100 years. At best, feeding has a limited nutritional benefit, often negated by undesirable, even catastrophic, behavioral and biological effects. Of course, we all have the best interest of wildlife in mind. However, we must ensure we understand the biology of the animals we re concerned about so our actions are truly beneficial. This is often the point of debate as society considers winter feeding mule deer. Our conventional wisdom, experience, and professional consensus is clear - feeding mule deer violates the most basic principle of population regulation within natural systems. At best, winter feeding for mule deer is only successful in making people who are compassionate about wildlife feel better and seldom are any benefits of winter feeding realized. Winter feeding of mule deer creates artificially high concentrations of animals, leading to increased risks, including disease transmission and predation. Winter-fed mule deer often die with full stomachs due to their inability to adapt to rapid changes in type and abundance of feed. More information on mule deer can be found at A product of the Mule Deer Working Group - Sponsored by the Western Association of Fish & Wildlife Agencies - Approved July 2013 Produced with support from the Mule Deer Foundation (

5 HIGHWAY EFFECTS ON MULE DEER MOVEMENT AND SURVIVAL Fact Sheet #3 OVERVIEW Mule deer need open landscapes to make a living. They move long distances daily and seasonally, and highways that cross mule deer ranges can be an obstacle to those movements. Many mule deer are killed on highways and many more have restricted their daily and seasonal ranges to avoid crossing busy highways. State and provincial wildlife and transportation agencies are working to keep deer off the roadway, while allowing them to get to the other side safely with specially designed crossing structures. AZGFD - George Andrejko BACKGROUND Mule deer populations are stable or declining in many of the western states and provinces. The causes for declines are varied and can be difficult to identify, but often are habitat related. High traffic roads can reduce habitat quality through the isolation of valuable resources. They can also be a source of direct mortality. If we can reduce highway mortalities while maintaining or restoring quality connected habitat, populations could reverse their decline and begin to grow. EFFECTS OF HIGHWAYS ON MULE DEER Highways affect mule deer in two critical ways; directly through mortality caused by vehicle strikes, and indirectly through fragmentation of habitat that can keep mule deer from acquiring needed resources and reduce genetic interchange. Fenced highways fragment the habitat, disrupt seasonal and daily movements, and can isolate breeding populations. Wide, unfenced highways with large traffic volumes can also be obstacles to deer movement. These disruptions to habitat and travel often decrease the survival or reproduction rates of individuals, which can lead to population declines. To be effective, wildlife and highway managers have to solve 2 fundamental problems. First, keep deer away from vehicles, and second, ensure that the highway remains permeable enough that the natural daily and seasonal movements of deer are not significantly impacted by the highway. Exclusionary fencing, used together with proper crossing structures, are the preferred and most successful methods to reduce vehicle-caused mortality and allow deer populations to move freely through the landscape. COST OF DEER-VEHICLE COLLISIONS TO SOCIETY Researchers have identified that each deer-vehicle collision costs society over $8,000. These costs include vehicle damage, insurance claims, medical bills, removal of carcasses, and recreational value of deer. These costs help justify mitigation measures such as wildlife crossings and fencing by illustrating the long-term cost-benefit of such structures. CROSSING STRUCTURES There are 2 basic types of wildlife crossing structures: overpasses and underpasses. Overpasses facilitate wildlife passage above a roadway, while underpasses are structures that allow wildlife to cross underneath a roadway.

6 HIGHWAY EFFECTS ON MULE DEER MOVEMENT AND SURVIVAL Overpasses can be thought of as bridges which cross over a road. They contain a continuous strip of vegetation which connects the natural landscape on one side of the road to the other side. There are less than 100 overpasses worldwide. The oldest overpass in North America was built for mule deer over I-15 in Utah. The best known and most studied overpasses occur in Banff National Park in Canada. Wayne Wakkinen Underpasses allow wildlife to pass under the road. There are primarily 2 types: bridges and culverts. Single-span bridges rest only on abutments at each end of the bridge, and multi-span bridges have intermediate support columns between abutments. Culverts pass under the road surface, and are entirely surrounded by the roadbed. Culverts come in a variety of sizes and shapes, including square, rectangular, elliptical, and cylindrical, and are commonly made of concrete or steel. Both deer and elk prefer to use overpasses or large, open underpasses. FACTORS AFFECTING MULE DEER CROSSING SUCCESS The size, type, and location of mule deer crossing structures are important attributes to their success because not all species or even all populations use these structures in the same way. Researchers have learned that deer prefer wildlife crossings that are open and spacious because the openness allows a better view of potential predators. The most important roadway attribute affecting use of crossing structures by large ungulates is road width. Wider paved roads require larger crossing structures to effectively pass deer. The location of mule deer crossing structures is the most important factor in their success. Knowledge of movement patterns of mule deer is an important prerequisite to the placement of these structures. Deer tend to use the same routes year after year, so the most effective crossing structures are those placed where deer traditionally cross roads. Locations of movement corridors can be identified through movement studies, roadkill, data or expert-based knowledge. Once movement corridors are identified, biologists and engineers should use landscape features when placing wildlife crossings, including Natural draws or ridge tops which help guide an animal to a crossing Areas covered with vegetation to help an animal feel safe, but that also allow some visual openness to look for ambush predators (i.e., mountain lion) Distant from human use Devoid of, or having minimal, snow cover Location of food and water sources Land ownership for long-term conservation Large habitat blocks on both sides of the highway Patricia Cramer FENCING - Fencing is an integral part in reducing deer mortality on highways. Fencing keeps deer off the road and away from vehicles, and it funnels animals into specially designed crossing structures. Without fencing, mule deer will not use crossing structures. Fencing must receive regular maintenance in order to retain its effectiveness in keeping wildlife off the highway. Fences must also be built with appropriate escape gates or jump outs so animals that end up on the wrong side of the fence can escape. Long stretches of fencing without crossing structures will reduce vehicle strikes, but are not recommended because they fragment the habitat and disrupt animal movement. More information on mule deer can be found at A product of the Mule Deer Working Group - Sponsored by the Western Association of Fish & Wildlife Agencies - Approved July 2013 Produced with support from the Mule Deer Foundation (

7 COMPETITION BETWEEN MULE DEER AND ELK Fact Sheet #4 OVERVIEW Numbers of elk have increased and mule deer (hereafter deer) populations have declined in many parts of western North America during the last several decades. These trends have led many people to question potential competition between the species. However, simply observing that elk and deer eat the same forage does not demonstrate competition. Impacts must take the form of decreased survival or productivity leading to decreased population growth to be important in population dynamics. AZGFD - George Andrejko FACTORS INFLUENCING COMPETITION Competition can occur when a species uses a resource (like forage), making it unavailable to another species (exploitative) or when social interactions keep another species from effectively obtaining some resource (interference). Deer and elk have developed a number of adaptations which influence their capability to compete with each other when resources are limited. ENERGETICS AND DIET Deer and elk generally select habitats and behave in a manner that allows them to maximize and conserve energy. In summer deer expend more energy than elk to stay cool because deer pant to dissipate heat whereas elk sweat extensively, a process that requires less relative energetic cost. In winter, moving in deep snow is more difficult for deer than elk. Thus, elk can often use more diverse areas and resources than deer in summer and winter. Elk are more likely to have a competitive foraging advantage over deer because 1) Deer have a smaller relative stomach volume, so deer need higher quality, more digestible forage, whereas elk can use lower-quality forage, but need large amounts, 2) Elk have a greater vertical reach than deer, allowing them to forage on taller plants, 3) Elk can take advantage of preferred deer foods such as shrubs in winter, but deer rarely make extensive use of common elk forages (like grasses), 4) Deer rely on more rapid digestion than do elk, so plant compounds that slow digestion may be more detrimental to deer, and 5) Elk usually eat a greater variety of plant species than deer and are less selective in which plant parts they consume. Severe winter weather typically contributes to lower mule deer survival and productivity than for elk. Thus, deer display more pronounced population fluctuations compared to elk. However, deer exhibit higher reproductive potential than elk, breeding more frequently as yearlings and often producing twins. Therefore, deer populations can rebound more quickly after declines if habitat conditions and other factors are favorable. HABITAT AND HUMAN ACTIVITIES Habitat changes caused by actions of European settlers led to increased shrub density in areas previously dominated by grasses or dense forests, which produced high quality deer habitat and high deer numbers during the early to

8 COMPETITION BETWEEN MULE DEER AND ELK IDFG - Paul Atwood mid-1900s. Nevertheless, these early and mid-successional habitats that favored mule deer gradually declined in value during the mid- to later 20th century or were replaced by forests or grasslands. Most of these changes tend to favor elk over deer. Evidence from research on the Starkey Experimental Forest and Range in Oregon indicates deer avoid elk and may therefore be excluded from some habitats when elk are present. Such interference competition could reduce deer productivity (such as cases were does are displaced from high quality habitat used for fawning and fawn-rearing). Human activity can have greater negative influence on deer in several circumstances: 1) Development and encroachment is generally more severe for deer because most development typically occurs on lower elevation winter range and elk tend to winter at higher elevations; 2) For the same reason (as well as greater avoidance of traffic by elk), deer mortality on highways and railways often far exceeds that of elk; 3) Winter feeding may exacerbate competition if higher concentrations of elk reduce forage or range condition; and 4) Human activity, including hunting, may cause elk to shift habitat use to areas of greater cover (shrub or forest) and consume forage normally used by deer. Both deer and elk may avoid pastures stocked with cattle, and deer may shift away from preferred habitats when cattle grazing is moderate to heavy, particularly in the absence of elk. If livestock grazing displaces both deer and elk, less habitat may be available, and competition between deer and elk could occur or increase. CONCLUSIONS AND RECOMMENDATIONS A broad statement that elk are responsible for mule deer declines is certainly not accurate. Several important mule deer populations have declined even without elk being present. Other deer populations have grown and responded well in conjunction with growing elk herds. If elk are having a negative influence on deer populations, what can managers do to positively influence deer? Acknowledgment that not every piece of land may be able to support large populations of both species is an important first step. Some options for management include 1) Select some areas (at landscape levels) where management will favor mule deer and others where elk will be favored, 2) Implement actions that return habitats to early successional stages with a lot of shrubs (such as prescribed fire and timber harvest to reduce stand density, and seeding with favored mule deer forages), 3) In areas where elk winter ranges do not overlap deer, improve habitat for elk (enhance grass-dominated ranges and reduce human activity), 4) Consider structuring elk hunting seasons to reduce potential impacts on deer, and 5) Consider reducing elk populations in selected areas (must include adequate monitoring of deer population responses). Finally, we must recognize that it took several decades of change to end up with degraded mule deer habitat and it may well take decades to reverse this trend. All stakeholders must remain committed to a long-term adaptive management process if we are to reverse mule deer habitat trends of the magnitude we have experienced. More information on mule deer can be found at A product of the Mule Deer Working Group - Sponsored by the Western Association of Fish & Wildlife Agencies - Approved July 2013 Produced with support from the Mule Deer Foundation (

9 CARRYING CAPACITY - HOW MANY DEER CAN WE HAVE? Fact Sheet #5 BACKGROUND The land can only support a limited number of animals before resources are depleted. Exceeding the land s resources results in poor animal body condition, fewer fawns surviving to adulthood, and eventual damage to the habitat. Therefore, understanding relationships between mule deer and their habitats is necessary for understanding deer themselves. Most livestock operators understand the concept of carrying capacity, which is the number of animals a given amount of land can support sustainably. A pasture or allotment can only feed a certain number of cattle in a given year. This concept also applies to wildlife. As animal density increases, or habitat quality or quantity decreases, deer productivity and survival decline. The number of deer the land can sustain over the long term ultimately is determined by the available habitat food, water, and space. It is important to note that carrying capacity varies seasonally, annually, and over time in accordance with changing habitat conditions. THE INFLUENCE OF HABITAT Mule deer habitat is affected by a combination of many factors, including fire suppression, oil-gas-mineral mining, habitat fragmentation, spread of invasive plants, drought, competition between species, livestock management, and other human factors such as urban development. Many of these changes to deer habitat reduce carrying capacity. Mule deer occur in a diverse set of environmental and climatic conditions and limiting factors to population size vary by habitat type. In much of their southern ranges, desert-like conditions prevail and precipitation is a key limiting factor to populations. In other climates, mule deer can be limited by winter range and snow accumulation. Mule deer thrive in young habitats, where forbs, grasses, and shrubs dominate the landscape. As forests age, less nutrients, light, and water are available for the forage plants deer prefer, so forage quality declines. Although the acres of habitat may not change, mule deer carrying capacity can vary significantly. Quality habitat increases fawn survival. This results in a productive population and more buck hunting opportunity because half of the fawns that survive to adulthood are bucks. MONITORING Because carrying capacity is always changing, it is difficult and expensive to measure over the entire landscape. Therefore, we monitor deer population performance in several ways that tell us whether the size of the population is appropriate for the amount and quality of available forage.

10 CARRYING CAPACITY - HOW MANY DEER CAN WE HAVE? Key indicators include density, survival, body condition (fat deposition), reproduction, and recruitment (juvenile survival to adulthood). In locally dense populations or high population years, it also is important to measure habitat conditions to prevent over-grazing of preferred forage plants. THE SCIENCE OF HABITAT LIMITATION Several studies have shown that deer populations are limited by available habitat. In Colorado, experimentally increasing deer nutrition increased fawn and adult survival by reducing predation and malnutrition rates. Another Colorado study showed that fawns wintering in habitat treatments that removed trees and weeds had significantly higher survival than fawns in untreated areas. In the Desert Southwest, research documented low precipitation is directly related to poor body condition and high mortality of adult deer due to malnutrition. Several studies and experiments have demonstrated that poor body condition also reduces pregnancy rates and fawn survival. MANAGEMENT IMPLICATIONS Managers use all of this information to align deer populations with the available habitat. These studies emphasize the importance of setting realistic population objectives to help prevent large-scale die-offs during drought or severe winters. Managers seek to achieve population objectives in several important ways: If a population is above its population objective, doe harvest can reduce the population to levels appropriate for the habitat. In winter-stressed herds, travel and recreation closures are used to reduce disturbance and increase survival. Managers can increase habitat quality through the use of prescribed fire or mechanical treatments to reduce tree cover and by making sure grazing levels are appropriate. Habitat conservation is critical for the future of mule deer. More information on mule deer can be found at A product of the Mule Deer Working Group - Sponsored by the Western Association of Fish & Wildlife Agencies - Approved July 2013 Produced with support from the Mule Deer Foundation (

11 UNDERSTANDING MULE DEER AND ANTLER POINT RESTRICTIONS Fact Sheet #6 Antler restrictions are harvest restrictions that limit buck harvest to animals that meet specific antler criteria. The most common type of antler restriction is a point restriction. Antler point restrictions have been used as a harvest strategy with the hope they will increase the number of large-antlered bucks in a mule deer population. Experience of many states and provinces with antler point restrictions suggest this harvest strategy has very limited potential to produce more trophy bucks and could result in other unintended challenges. BACKGROUND Increasing the number of big-antlered bucks is typically the basis for hunter demands to implement antler point restrictions. The idea seems straightforward and promising; if we just don t allow hunters to harvest young bucks, they will grow older and bigger and be available for harvest later. Most western states and provinces have, at one point in time, employed some type of antler point restriction attempting to increase the number of trophy bucks in their herds. THE GOOD Decreases hunter pressure and total buck harvest by discouraging some hunters who do not want to be restricted to a particular antler-sized buck. This can be beneficial when harvest is heavy in relation to the number of available bucks, but not heavy enough to warrant changing to limited quota seasons. In some cases, antler point restrictions have increased the proportion of bucks in the population, but this effect may not be long-lasting. In remote areas with limited access, antler point restrictions have been used in combination with general seasons to maintain hunter opportunity. THE BAD Antler point restrictions focus all the hunting pressure on the oldest age classes of bucks, gradually decrease the average age of the buck segment of the population, and make it more difficult for bucks to reach the older age classes due to the displaced harvest pressure. Antler point restrictions have been shown to reduce the number of trophy bucks over time by protecting only the smaller-antlered young bucks. Antler point restrictions do not increase fawn production or population size. Even in herds with very low buck:doe ratios (<10:100), pregnancy rates are well over 90%. Large increases in buck ratios result in relatively few, or no, additional fawns.

12 UNDERSTANDING MULE DEER AND ANTLER POINT RESTRICTIONS Shawn Gray Antler point restrictions often fail to provide the intended benefit as this large two-point mule deer buck is not typically what hunters aspire to create or maintain with antler point restrictions. THE UGLY Antler point restrictions dramatically reduce hunter participation, harvest success, and total harvest. Antler point restrictions increase the number of deer shot and illegally left in the field; this can be significant, and has been documented in Wyoming, Colorado, Utah, Oregon, Nevada, and Montana. Antler point restrictions can cheapen the value of young bucks by changing the threshold for success from a buck to a quest where only a big buck will do. Antler point restrictions may discourage hunters (especially beginning and young hunters) by increasing the difficulty of locating and identifying legal deer. CONCLUSIONS After decades of use and many evaluations reporting disappointing results, most western states and provinces have discontinued statewide antler point restrictions. The two main reasons for abandoning widespread antler point restrictions are (1) unacceptable accidental-illegal kill, and (2) harvest mortality was increased (focused) on the very age classes they intended to promote. Available data and experience suggest antler point restrictions result in no long-term increase in either the proportion or number of mature bucks, or the total deer population. A few jurisdictions still have limited areas with antler point restrictions, due to hunter preference. The use of antler point restrictions in a combined strategy with general seasons is used in at least one case to maximize hunting opportunity. There are additional reasons why the widespread use of antler point restrictions has not been successful. Research has shown buck fawns born to does in poor body condition have difficulty outgrowing the effects of poor body condition at birth, and may never reach their genetic potential for antler growth. Regulations protecting these bucks from harvest are counterproductive to the intended benefit. Most western states and provinces have concluded that sustainable improvements in buck:doe ratios and the number of mature bucks can only be realized by reducing harvest through 1) a limited-quota license system that decreases overall total buck harvest while allowing some level of doe harvest, or 2) setting a very short hunting season in early fall when more mature bucks are less vulnerable. It has been suggested while antler point restrictions may increase the proportion of bucks in certain populations with low buck:doe ratios, there is no evidence they substantially increase the total number of adult (mature) bucks. More information on mule deer can be found at A product of the Mule Deer Working Group - Sponsored by the Western Association of Fish & Wildlife Agencies - Approved July 2013 Produced with support from the Mule Deer Foundation (