Economics and human Interactions of the Wild Hog in Texas

JOEL P. BACH, M.S. Candidate in Agriculture Economics/Research Assistant in Rangeland Ecology and Management, Texas A&M University, College Station, Texas

J. RICHARD CONNER, Professor of Agriculture Economics and O’Conner Professor of Rangeland Ecology and Management, Texas A&M University, College Station, Texas

Abstract: Wild hogs continue to be a major management problem in 19 states. In Texas, both feral hogs and/or the Russian Boar exist in free-ranging populations numbering in the millions. At present, these populations continue to expand, and now are present in almost all land resource areas. Wild hogs have significant economic presence in the ranching and farming business. Hogs represent both a valuable asset and a significant liability to agricultural producers and other land owners/managers.

Although wild hogs have been studied in terms of ecological damage, population dynamics, and parasitology, little research has centered around the economic effects which define the current problems in management efforts. A closer look at the underlying socio-economic reasoning and existing preferential and institutional constraints is presented. Values, preferences, and management incentives are examined. Consideration of private and public rights and ecological/legal liability is essential.

Changes in management must proceed under the economic theory of improvement in economic efficiency by the use of management alternatives. Areas of consideration for new approaches are delineated. The new approach is defined as a sound process of management planning that considers all inputs. This process may yield the possibility of changing management efforts from being anti-symptomatic to anti-problematic. Under this more holistic approach, more successful management of the wild hog in Texas can be possible and sound results can be accomplished.


The wild swine may be the single most destructive wild, free-ranging ungulate which inhabits Texas Rangelands. The term wild swine, as used herein, does not apply to the Javalina, or peccary, an indigenous wildlife species. It applies to the mixed populations of the feral hog and the Russian boar. Both feral hogs and the Russian boar are physiologically similar to each other and represent similar benefits and liabilities to managing interests on agricultural lands (Bratton, 1977).

Neither species is indigenous to Texas, but both have successfully inhabited most parts of the state on a wild, free-ranging basis. All members of the swine family are omnivorous, which allows them a great advantage over indigenous wildlife, of which few are as efficient users of food resources. Both types are reported to eat plants, rodents, birds, fish, snakes, frogs, invertebrates, and carrion. (Henry 1969, Henry and Conley 1972, Challies 1975, Scott and Pelton 1975, Springer 1977, Tuff 1977). In the remainder of this paper we will refer to both species as wild hogs or simply “hogs”.

Management of wild hog populations in Texas is very different from region to region, county to county, and from producer to producer. This appears to be due, in part, to differences in opinion concerning the animals, and to the high degree of variation in both the vegetative and soil resources from one operating unit to the next. It is also due to the differences in climate between the major rangeland resource areas.

Hog management goals conflict primarily due to the differences in individual producer’s values for the presence of the wild hogs on farms and/or ranches. Cases exist where both liability and assets are present upon single operating units, depending upon the general perception (Rollins, 1992a). Farmers generally view the hogs as a major liability due to the damage to crops and facilities that they often inflict. Cattle ranchers, unless in areas of high hog populations, are generally more indifferent to the presence of the hogs. However, sheep and goat producers usually view the hogs as a significant problem because of their tendency to prey upon lambs and kid goats; in some cases, hogs also kill adult goats and sheep.

The hunter or wildlife photographer further presents differing opinions. Some hunters enjoy pursuing wild hogs with several types of weaponry. The sporting aspects of hog hunting appear to have considerable value (Adams and Thomas 1983). One of the appealing aspects of hunting hogs is that it can be experienced year around. Thus, many hunters prefer to lease land where hog hunting is available in addition to traditional wildlife which must be hunted in their respective seasons.

Other hunters do not care for the hogs, and view them only as an additional liability to sound wildlife management. The hindrances to wildlife takes several forms: competition for food, depredation, disease transmission, and habitat degradation. It is doubtful that many wildlife photographers or observers pursue the wild hog as a primary quarry although these uses have considerable value (Pope, et al., 1984).

Wild hogs represent a significant potential source of revenue as wild meat, as many are currently trapped and sold for both immediate and later slaughter for human consumption. This opportunistic use of wild, free-ranging sources of meat may have large benefits to general populations, as the animals are sometimes donated to charities or offered free for the taking. However, the presence of internal parasites can be a problem, and often, the meat is not processed in accordance with regulations required for public sale (Barrett-Connor et al. 1976, Tisdell 1979).

The General Problem

The rights to private ownership and use of animals differs depending on whether the animal is considered to be wildlife or livestock. As both feral hogs and Russian Boars are considered to be livestock in Texas, their ownership is generally assumed to belong (de facto) to the private citizens who control the land that they inhabit (Texas Legal Code, 1993). Differing opinions of ownership for the hogs results in management conflicts; these may be both inter- and intra-managerial among production units.

Such designation limits the ability of agencies such as the Animal Damage Control Service to control hog damage. A lack of ingress rights to private land is a major hindrance to efforts to control populations of the animals in areas adjacent to agriculture crops. Many problems such as this are important considerations in the management of the wild hog. In order to solve such problems, a closer look at specific problems presented by the presence of the animals is in order.

Almost all hog-related problems are defined to be of a biological, social, institutional, or economic in nature. A biological problem may be the presence of a disease vector in the hog population. A social problem may relate to land owner/manager freedoms or rights, which are often violated by hogs which cross property lines. Social problems are also rooted in people’s different opinions of proper use and management of all animals (ie. animal welfare). This is especially prevalent with free-ranging animals which may be perceived as wildlife (Brokaw, 1978).

An institutional type of problem exists due to the constraints upon hog management imposed by property and boundary rights and related legal interpretations and regulations (Nielson, et al. 1986). Hogs are classified as feral livestock (Texas Legal Code 1993). Unlike other livestock, however, land owners/managers are not held responsible for the damage that their escaped animals cause. Depending upon the county and the current status of “open range” laws, fencing has an influence upon the liability of the land owner/manager regarding the movement of the hogs (Fambrough 1993). Problems of this type will probably intensify.

Wild hogs in Texas show distinctly similar liability and animal damage control problems to many other feral animals, such as the wild horse, in many western states. More like the problems with exotic animals in Texas, those who suffer damage from the hogs are afforded the right of controlling the problems by capturing the animals for sale or killing them. However, it must be noted that the hogs have not been afforded the interest and concerns afforded to other exotics (Young 1973, Ramsey 1968, 1969 Jackson 1964). Although the hogs are not wildlife, they are subject to wildlife damage control efforts.

The hogs are often perceived to be wildlife, which are not owned by individuals. As livestock, the hogs are not generally claimed by landowners as property. Thus, wild hog damages are not liabilities which can be transferred to their owners. Landowners who utilize the hogs for income practice opportunistic resource use. This use of the hog resource is not legally regulated and provides no protection for land owners/managers who face the liabilities which result from this practice (Texas Parks and Wildlife 1976, Knight and Morgan 1989).

Probably the most important problems are those founded in economics. Hogs represent both an economic asset and a significant financial liability. The economic problems are mostly distributional; the benefits and the liabilities of the hogs are not equal among different land use operations. Almost all human activity relates to economics; the gains resulting from the investment of labor and capital drive management decisions. These decisions are not necessarily optimum for others who have conflicting management objectives.

Consideration must be given to those that have vested interest in any activity which is affected by the hog’s presence. Although the hogs are not wildlife, their effects upon the wildlife community is significant, as is their effects on the present populations of domestic livestock. This, coupled with consumption and destruction of agricultural crops is significant (Springer 1977). Cooperation amongst competing and conflicting resource uses is necessary for an alignment of management efforts.

In light of the complex nature of land and animal ownership, private rights, and differences in values, most efforts at understanding the problems associated with management of wild hogs have been far too shallow. Current management efforts may be purely anti-symptomatic in nature. It is doubtful that a single change in management prescription, animal damage control practice, or legislation will offer a conclusive solution to all the problems in all resource areas. It is likely, however, that all three may be combined in different manners to improve future management results.

The remainder of this paper offers a closer look at the underlying socio-economic reasoning and existing economic and institutional constraints which pertain to wild hog management. More information on values, preferences, and social and economic management incentives is examined, with some consideration of private and public rights and ecological/legal liability. The primary objective is to determine if changes are needed in the current approach to managing wild hog populations.

A Greater Understanding

The present problems of wild hog management are not bad nor good, they are just problems. The consideration of all inputs is a key concept to finding answers. Biological facts, private and societal rights, and economic incentives must all be considered. Human nature dictates different decision-making processes, and consideration of these differences is critical to finding solutions. If a good outcome is to be attained, a search for improvement should begin in a good process. Consideration, cooperation, and increased understanding are the basic components of a good process.

Biological Aspects

It is important to understand the biologically significant features of the wild hog. Some aspects of the wild hogs have been widely researched. These areas include immunological, toxicological, behavioral, and dietary studies (Benke 1973, Ellisor 1973, Jackson 1964, Ramsey 1968, Coombs and Springer 1974). Biological research may be lacking in some key areas, such as reproduction potential, population dynamics and range expansion (Tipton, 1977). However, general information regarding the hogs is increasing (Taylor 1992, Rollins, 1992b, 1992c). Detailed information on these topics will not be presented herein, but referral is made to the many publications which can be located in the libraries of the state agricultural colleges.

In assessing the current socio-economic conditions which hinder hog management, several biological assumptions must be made, as they offer rigid constraints to present efforts of management. First, regardless of the opinions surrounding the presence of the hogs, hogs are indeed present, and no blame is necessary to simply recognize that they present a problem which must be managed. Secondly, all wild hogs cannot be removed by either landowners or governmental agencies. They are far too prolific, far too elusive, and located, for the most part in areas where accessibility to them is limited. Thirdly, common fencing systems in use today are not capable of controlling their movement and expansion. It is safe to say that wild hogs must be assumed to be a permanent fixture upon the Texas landscape.

Social/Institutional Aspects

Several constraints to wild hog management are related to the institution of property rights. Property rights in the U.S. and the current system of resource ownership are founded in an intricate pattern of historical inputs. The institutional system which delegates the ownership of animal resources in the United States is based, in part, upon the system of pre-American Europe. The system used in the United States has a primary foundation in achieving social goals, which are the rooting of distributional problems.

In the original plans for resource distribution, the U.S. constitution allowed states to withhold wild animals in “public trust” for the citizens (Brokaw 1978). Thus, all citizens, in aggregate, perceive they have an inherent right to behold, control, and manipulate these animals for the population’s overall interest (Tober 1981). This “public trust” applies to all species of wild animals except those which are classified as livestock. However, the “public interest” is difficult to determine and is dynamic over time.

Of all exotic and feral ungulates, only the Aoudad is partially recognized as a game animal in Texas, (Butts 1979, Payne, et al. 1987) Therefore, hog populations in Texas are not controlled under state wildlife management laws. Even management efforts that are founded in treating the hogs as wildlife are hindered by the weakness of state game management laws in Texas. This weakness results from an effective transferral of wildlife ownership to the private landowner due to the strength of property rights (Teer and Forrest 1968, Burger and Teer, 1981). Hog management has criteria that apply from state agricultural legal codes, but these do not all apply to the hogs as with other livestock.

Hogs are generally managed more like other wildlife. However, as both feral hogs and Russian Boars are considered livestock, their ownership is determined by the laws which govern livestock ownership. As with other livestock, the decision to clear a property of the species in question is based on the value of that species. Wild hogs clearly demonstrate both positive and negative values on landowners. Management of their populations is, for the most part, an operation to operation decision. As they are considered livestock, the general public has much less influence on their management than is the case with wildlife.

Economic Aspects

Specific values for the benefits and liabilities of the wild hog in Texas are not widely known. Although researchers have found difficulty in placing values upon wild animal resources, it is assumed that they represent both a tremendous asset and a considerable liability to different landowners in Texas. These financial considerations apply to all free-ranging animals, including both game and nongame and both indigenous and exotic species. Those with negative perceptions attempt to control wild populations, those with positive perceptions are known to “pander to excess”, or act in overt benefit to foster the species in question.

As mentioned before, the ownership of feral animals is a questionable concept. However, an analysis of the opportunistically harvestable benefits is appropriate, given current Texas law. Estimates of these benefits seem easily attainable, however, little information is available on the sales or leasing income for Texas land owners/managers relating to the wild hog. No attempt to estimate the exact benefit represented by the hogs is made herein. However, it is generally acknowledged that the only significant financial benefits reported by land owners/managers are represented by the practices of hunting and trapping hogs for sport and meat.

The hunting industry in Texas is well established. Wildlife in Texas are valued in excess of $300 million (Steinbach, et al. 1986). Whitetail deer alone represent a multi-million dollar industry in the state (Pope, et al. 1983). This income is important to the sustainability of many agricultural operations (Forrest, 1968 Nielson, et al. 1986 Terrill, 1975). Some studies have shown that without the addition of wildlife income, many ranches would return less than three percent interest to investment. This inclusion of wildlife enterprises in the agricultural or other land management operations increases property values and adds income to annual cash flow statements. These enterprises are made possible in Texas by the rights of private land owners/managers to control access to game by regulating trespass to the land.

Literally hundreds of properties in Texas offer hunts which include a chance to kill a wild hog. A treatment of wild hogs as a wildlife resource yields benefits mostly in the area of fee hunting. Many charge for this purpose, and many others offer it as an added bonus for other types of hunts. Revenues received for this purpose are known to vary between negative values (paying for the hunters to hunt the hogs) to positive (trophy charges) in excess of $500 per animal. Nearly all lessors of deer hunting rights include the hogs as an added attraction for hunting, even if there is not an additional charge.

Wild hogs also represent a semi-controllable source of meat. The owner and operators of the agriculture operations may consume this meat, sell the live animals, or give them to willing and receptive individuals. Many young male hogs are captured and castrated, then released to fatten, where they will be later shot or re-captured, killed, and eaten. Live hogs are often sold to interested individuals, who often butcher them for themselves. Killing the hogs and donating them to individuals is also a common practice and a good source of meat to those in need (Talbot, et al.). However, it must be noted that by law, the carcasses or meat is not generally approved for resale.

Negative values are faced by the land owner/manager who has properties which are damaged or destroyed by wild hogs. Several examples of damages resulting from hog populations have been reported. Hogs trample and eat crops; they kill and eat young lambs, kid goats, and other wildlife; they eat eggs and destroy bird nests; and they damage fences. Further damages to equipment has been documented; these include wildlife feeders and land surface damage which results from rooting done by the hogs.

Hogs also eat and waste feed provided by farmers and ranchers for other livestock. They consume and/or damage mineral and protein supplement blocks and destroy feeding equipment. Hogs also have the ability to transmit several types of diseases to other animals. Of extreme importance is the possibility that wild hogs can cause injuries to humans. Injuries often take place in capturing and handling the hogs. Another, more dangerous possibility exists in the form of accidents involving highway traffic and the free-ranging hogs.

These positive and negative values and the extent of their occurrence are being studied by the authors at Texas A&M University in the spring of 1993. Individualized interviews of selected operators in various resource areas of the state were initiated in January of 1993. These interviews have been designed to facilitate the construction of case studies which depict the different kinds of values that wild hogs represent. The interviews are exhaustive with respect to each individual’s valuation of the benefits and liabilities of the wild hogs. Enterprise budgets will be constructed for each operation to delineate the impacts of the hogs on the various enterprises of that operation.

A New Focus on the Problem

In this section, some relevant principles originating in the field of economics will be presented and explained in a simplified manner. Examples which apply these principles to an analysis of wild hog management efforts are extended. Many of the concepts that will be presented require only intuition and a common knowledge of the process of human choice for understanding. For further understanding and/or relevant reading, the authors refer the reader to part II in Resource Economics (2nd Edition) an understandable text written by Alan Randall (1987). Clarification of the need for social and ecologic considerations in economic theory is extended.

The wild hog problem represents, to economists, a classical problem of negative externalities. A externality is a secondary effect that exists because of another event. An externality can be either positive or negative; positive represents a gain to those secondarily affected and negative represents a loss. An example of a positive externality is the increased plant response in wheat crops resulting from a decision to graze them. A gain in weight to the animals is the primary event needed to generate revenue, but the higher wheat yields resulting from the physiological response in the wheat is also a gain.

A negative externality is where a primary event causes a loss to others as a secondary effect. The problem of hog damage is similar to other classical examples. These include smog and air pollution from factories, and cattle which break fences and eat farmer’s crops. Both represent production processes which are a benefit and source of revenue as a primary event, while representing a burdensome secondary effect upon those surrounding them which suffer losses. In the case of the hogs, the offending party is the land owner/manager who maintains a reservoir of wild hogs. The offended party is the agricultural producer who suffers losses due to the presence of the hogs.

Problems involving externalities are usually solved by either of two means. First, governmental agencies can control the damage by regulations which minimize negative influences, such as zoning or taxation. Zoning allows the offended party to operate in areas where damage will be minimized. Taxation targets an acceptable, tolerable amount of damage above which excesses are measured and charged to the offending party. To apply this remedy to the problem of wild hog damage would require that areas such as counties or precincts need be declared “no hog zones”, and mandate that fines and taxes be determined for violators.

In this kind of arrangement, government agency personnel would be able to actively control wild hogs on any land in the declared zone. Also, persons who did not comply with the provisions of the zoning requirements could be taxed or fined. A program such as this additionally implies that if a region was not declared a “no hog zone”, that landowners could propagate wild hog populations without fear of recourse from other citizens in the area. The current legal framework and nature of the wild hog problem prevents agencies from using these means to lessen existing damages. However, Texas County Commissioner’s Courts have mandated certain harvest restrictions regarding other exotics (Butts 1979, Payne, et al. 1987).

A second method of dealing with externalities involves an exchange of funds by which both parties can equalize the values of benefit and liability. This situation could be designed to be a social optimum, which is not necessarily the most favorable situation for either party, but is the best that can be attained when all parties desires are considered together. In this arrangement, the offending party pays the offended party for damages, or the offended party pays the offending party to take measures to lessen the extent of the damages. This remedy, however, seems quite inappropriate for dealing with the problems of wild hogs because of the difficulty associated with defining the offender and the discovery of the proper amount of exchange.

The problem of management for a species with conflicting values is not new. It occurs in many areas of Texas with both exotic and native species of deer, sheep, and antelope. It is highly probable that many instances exist where land owners/managers with a common property line have completely differing opinions of the value of the animals. Obviously the same applies to their individual management strategies. These problems are pervasive with the wild hog.

Almost all offended individuals interviewed by the authors have indicated common problems. They universally agree that the different land utilization strategies on adjoining properties specifically agitates the amount of damages the hogs impose upon agricultural resources. Most feel that differences in values held for the hogs have allowed improper incentives to mandate the existence of “reservoir” areas upon which the hog populations exist. Lastly, some feel that absentee ownership is more pervasive than in the past, and therefore, management programs which require active participation have a high failure rate.

What Can Be Done?

It is likely that a single, simple solution is completely unattainable. However, potential improvement from the status quo may be possible. Any affected person has goals, motivations, and objectives. Each has something that other people may need and some that they may not. If there is any chance of reciprocal trading in those aspects, economics may help define an arrangement whereby the position of all individuals, in the aggregate, is slightly bettered. Increased consideration of social inputs is needed.

The use and management of wild hogs is impacted by the desires of the general public as well as affected land owners/managers. The influence of the public interest cannot be ignored. If the public perceives that they have inherent rights relating to free-ranging animals, they may demand management changes which consider the population’s overall interest. As with wild horses, wild hogs may be perceived by the public to be wildlife, and may demand that the state be charged with their management and be held accountable for any damages they inflict upon private property.

Land owners/managers who suffer damage by hogs most often do so from hogs which cross property lines. The lack of definition of ownership for the hogs also exists with other forms of exotic wildlife that are classified as livestock in Texas. These animals, for the most part, do not cause a high degree of damage to producers and readily provide many of them with revenues. Hogs, however, multiply quickly, do not respond readily to control measures, are not confinable by conventional fencing systems, and cause significant damage to land owners/managers.

Attempts to define property rights which pertain to the hogs are needed. A definite need for increasing management effectiveness is to find a better definition of ownership for these animals. Ownership of the hogs should be established within Texas law. The obvious choices are to designate ownership to either those whose land they live upon or to the state.

The establishment of legal liability for damages caused by the hogs is, from an ethical and moral standpoint, very important to the discovery of future solutions. This is a very basic need if ownership of the hog is continued to be left in private hands. Continuation of the classification of the hogs as livestock is an effective reinforcement of the status quo situation. It must be noted that a change of status from livestock to wildlife would likely find little opposition from the general public. Those leading the opposition would likely be individuals who profit from the presence of the hogs at the expense of those who suffer damage.

Opportunistic use may need to be regulated by the state in order to provide for protection of land owners/managers who face the liabilities which result from this adopted practice. A continuation of allowing the harvest of opportunistic benefits holds potential for ecologic degradation and disaster. Those land owners/managers who perceive a positive value for the hogs will increase attempts to further protect wild hog populations. Identification of those who retain the benefits is necessary to identifying who is responsible for increases in populations which become uncontrollable. Present attempts to solve hog damage are not generally cost effective, and the continuation of present means seems to be anti-symptomatic in nature.

An increased emphasis upon the understanding the economics of the problem will yield sound conclusions. Inefficiencies which hinder the attainment of a social optimum should be regulated by taxes or controlled harvest of wild hogs by permit. Incentives which could assist management efforts of controlling the hogs population need to be found. The nonexclusive nature and conflicting aspects of wild hog ownership are areas of needed research. Future management efforts must improve the distribution of all benefits and liabilities that the wild hogs currently represent in Texas. A better understanding of all inputs will allow the long process of developing better comprehensive management strategies to begin.

Literature Cited

Adams, C.E. and J.K. Thomas. 1983. Characteristics and Opinions of Texas Hunters. 1983 Proc. Annual Conf. S.E. Assoc. Fish and Wildl. Agencies 37:244-251.

Barrett-Connor, C.F. Davis, R.N. Hamburger, and I. Kagan. 1976. An Epidemic of Trichinosis After Ingestion of Wild Pig in Hawaii. J. Infectious Diseases 133(1976):4. Pgs. 473-477.

Benke, A. 1973. Wild Hogs – The Ugliest Texans. Texas Parks and Wildlife. 31(1):6- 9.

Bratton, S.P. 1977. Wild Hogs in The United States – Origin and Nomenclature. Pgs. 1-4 In: Research and Management of Wild Hog Populations. G.W. Wood, ed. Belle W. Baruch Forest Science Institute of Clemson University. Georgetown, S.C.

Brokaw, H.P. ed. 1978. Wildlife and America. Council in Environ. Quality Sponsored by the: USDI – USFWS, USDA – Forest Serv. and NOAA. 400 pp.

Burger, G.V. and J.G. Teer. 1981. Economic and Socioeconomic Issues Influencing Wildlife Management on Private Land. Pgs. 252-278 In: R.T. Dunke, G.V. Burger, and J.R. March, eds. Wildlife Management on Private Lands. LaCrosse Printing, La Crosse.

Butts, G.L. 1979. The Status of Exotic Big Game in Texas. Rangelands 1(4). August, 1979.

Challies, C.N. 1975. Feral Pigs (Sus scrofa) on Auckland Island (New Zealand): Effects on Vegetation and Nesting Sea Birds. New Zealand J. Zoology 2(1975):4. Pgs. 479-490.

Coombs, D.W. and M.D. Springer. 1974. Parasites of Feral Pig X European Wild Boar Hybrids in Southern Texas. J. Wild. Disease. 10(4):436-441.

Ellisor, J.E. 1973. Feral Hog Studies – Final Report. Project No. W-101-R-4, Red. Aid in Wildlife Rest. Act.

Fambrough, J. Personal communication with authors, January, 1993. Texas A&M University professor of Agricultural Economics – Texas A&M Real Estate Research Center.

Forrest, N.K. 1968. Effects of Commercialized Deer Hunting Arrangements on Ranch Organization, Management, Costs, and Income – Llano Basin of Texas. M.S. Thesis, Texas A&M University. College Station. 135 pp.

Henry, V.G. and R.H. Conley. 1972. Fall Foods of European Wild Hogs in the Southern Appalachians. J. Wildl. Manage. 36(1972):3. Pgs. 854-860.

Henry, V.G. 1969. Predation on Dummy Nests of Ground-Nesting Birds in the Southern Appalachians. J. Wildl. Manage. 33(1969):1. Pgs. 169-172.

Knight, J.E. and C.H. Morgan. 1989. Legal Liability of Ranchers with Fee Hunting Enterprises. Draft of Research Report, Dept. Fisheries and Wildlife Science, New Mexico State University.

Jackson, A. 1964. Texotics. Texas Game and Fish Comm. 22(4):7-11.

Nielson, D.B., F.J. Wagstaff, and D. Lytle. 1986. Big-Game Animals on Private Range. Rangelands 8(1). February, 1986.

Payne, J.M. R.D. Brown, and F.S. Guthery. 1987. Wild Game in Texas. Rangelands 9(5). October, 1987.

Pope, A.C. III, C.E. Adams, and J.K. Adams. 1983. The Economic Value of Wildlife Resources in Texas. Paper presented at the annual meeting of the Western Assoc. of Agri. Econ. Laramie, WY. Pgs. 51-60.

Pope, C.A., C.E. Adams, and J.K. Thomas. 1984. The Recreational and Aesthetic Value of Wildlife in Texas. J. Leisure Res., 16(1984):51-60.

Ramsey, C.W. 1968. State View of Governmental and Private Programs of Introduction of Exotic Animals. Symp., Introduction of Exotic Animals. Texas A&M Univ. College Station. p. 9-10.

Ramsey, C. 1968. Texotic line-up. Texas Parks and Wildlife 25(4):3-7.

Ramsey, C. 1969. Texotics. Texas Parks and Wildl. Dep. Bull. 49:1-46.

Randall, A. 1987. Resource Economics: An Economic Approach to Natural Resource and Environmental Policy. Second Edition. John Wiley & Son. New York. 434 pp.

Rollins, D. In Search of Camouflaged Cowboy Hats: A Metaphor for Resolving Wildlife/Livestock Conflicts. 1992a. The Cattleman. Vol. 79 (1992):36-43. August, 1992.

Rollins, D. Feral Hogs: Dr. Jekyll or Mr. Hyde? Escaped Porkers Going Wild in Texas. 1992b. The Cattleman. Vol. 79 (1992):60-61. August, 1992.

Rollins, D. Feral Hogs: The Good, The Bad, and The Ugly. 1992c. SRM Newsletter, Texas Section, The Society for Range Management.

Ruddle, W.D. 1975. Helminth parasites of feral swine from the Aransas National Wildlife Refuge. M.S. Thesis. Texas A&M University. College Station. 43 pp.

Scott, C.D. and M.R. Pelton. 1975. Seasonal Food Habits of the European Wild Hog in the Great Smoky Mountains National Park. Pgs. 585-592 In: Proc. 29th Ann. Conf. of the S.E. Assoc. of Game and Fish Comm.

Springer, M.D. 1977. Ecologic and Economic Aspects of Wild Hogs in Texas. Pgs. 37-46 In: Research and Management of Wild Hog Populations. G.W. Wood, ed. Belle W. Baruch Forest Science Institute of Clemson University. Georgetown, S.C.

Steinbach, D.W., J.R. Conner, M.K. Glover, and J.M. Inglis. 1986. Economic and Operational Characteristics of Recreational Leasing in the Edwards Plateau and Rio Grande Plains of Texas. In: Trans. 52nd N.A. Wildl. and Nat. Res. Conf. Pgs. 496-515.

Talbot, L.M., W.J.A. Payne, H.P. Ledger, L.D. Verdcourt and M.H. Talbot. 1965. The Meat Production Potential of Wild Animals of Africa. Commonwealth Agr. Bureaux. Farnham Royal, Bucks, England. Tech. Comm. No. 16.

Taylor, R. 1992. The Feral Hog in Texas. Texas Parks and Wildlife Dept. Fed. Aid Rpt. Series 38. Fed. Aid Proj. W-125-R.

Teer, J.G. and N.K. Forrest. 1968. Bionomic and Ethical Implications of Commercial Game Harvest Programs. Trans. N. Amer. Wildl. and Nat. Res. Conf. 33:192-202.

Terrill, C.E. 1975. Game Animals and Agriculture. J. Anim. Sci. 40(5):1020-1022.

Texas Legal Code. 1993. Current Texas Agriculture Code – Laws and Regulations. Various sections pertaining to livestock ownership.

Texas Parks and Wildlife. 1976. Texas Wildlife Laws and Statutes. Texas Parks and Wildlife Dept. 2 Vols.

Tipton, A.R. 1977. The Use of Population Models in Research and Management of Wild Hogs. Pgs. 91-101 In: Research and Management of Wild Hog Populations. G.W. Wood, ed. Belle W. Baruch Forest Science Institute of Clemson University. Georgetown, S.C.

Tisdell, C.A. 1979. On the Commercial Use of Feral Pigs in the Meat and Related Trades. Dept. of Economics, University of Newcastle, N.S.W. 2308, July, 1979.

Tober, J. 1981. Who Owns the Wildlife: The Political Economy of Conservation in 19th Century America. Greenwood Press. 300 pp.

Tuff, M.H. 1977. The Effect of the European Wild Boar (Sus Scrofa) on the Woody Vegetation of Gray Beach Forest in the Great Smoky Mountains. Mgmt. Rpt. #18. USDI Nat. Park Serv. Gatlinburg, TN.

Young, E.L. Jr. 1973. Exotics. Texas Parks and Wildl. 31(8):2-8.