Over-exploitation, usually combined with habitat destruction, threatens about one third of the endangered mammals and birds of the world (Lande et al. 1994). The majority of world efforts to conserve biodiversity are concentrated on conservation of these threatened species. These efforts, for the most part, concentrate on legislation to protect these animals from hunting and trapping, protecting their habitat and other resources necessary for their existence. By contrasts, much effort is invested eradicating abundant pest species. Mostly, this is done by lethal methods, such as poisoning, shooting or trapping. In most cases, there is public consensus supporting these actions. However, occasionally the threatened species is also a pest, resulting in a difficult-to-solve man-nature conflict that may illicit extreme responses from both conservationists on one side and farmers on the other. At times, such responses may deviate from the frame of the law.

The wolf (Canis lupus), possibly, represents the worlds most acute example of such a conflict. As a large predator, the wolf falls naturally under two of three rarity categories: habitat and density (Kunin and Gaston 1993). Thus, the species is highly susceptible to extinction due to human activities. Wolves, however, also cause damage to livestock and are viewed as a serious threat by cattle growers. (Fritts 1990). The wolf's skill in cooperative hunting and its ability to overcome problems while seeking domestic prey has caused man to fear the wolf. Throughout history man regarded the wolf as undesirable and has sought to exterminate it. In more than one half of the countries of the world where the wolf existed, man has either succeeded, or is on the verge of succeeding, in exterminating the wolf (Anonymous 1993). Thus, as new attitudes developed towards conservation in the 1960s, wolf management became a complex and controversial public issue.

The wolf population in northern Israel is a unique isolated threatened population consisting of no more than 200 animals. Less than 40 years ago, this population was virtually non-existent. However, since the formulation and implementation of the Wildlife Protection Law in Israel in the early 1960s, the population has increased steadily. In parallel to this increase, depredation on newborn calves has been steadily rising causing discontent amongst cattle growers and increasing pressure to eradicate the wolves. However, due to its limited size the population is at a constant risk of extinction (Shaffer 1981). Consequently, conservation authorities in Israel have been reluctant to implement a strong wolf culling program which would increase considerably its extinction probability (Lande et al.1 995). Over time, tension between the cattle growers and green organizations increased, heightening the level of animosity and distrust, leading eventually to illegal attempts to poison wolves and killing other threatened wildlife in the process.

In order to preserve healthy population of wolves in areas where livestock are raised, there is a need for imaginative, varied, non-traditional, and non-lethal methods to reduce inevitable predator-livestock conflicts (Linnell at al., 1996). Such non-lethal methods for control of predators have achieved higher levels of community acceptance than other methods (Fig. 1).

The only effective long-term solution in such situations is separating the predator (the wolf) from its domestic prey (cattle), forcing it to rely more on wild prey items. Such separation can be done either by physical barriers, protection of the herd, or repelling and deterring the predator. A physical barrier, such as massive conventional fencing, is the only technique that presently can guarantee positive results. This technique has proven itself with other vertebrate pests where the defended product was an agricultural crop. However, in the case of cattle held on an open range, the size of the area needed for the cattle and the need to transfer the cattle periodically depending on range conditions, makes massive fencing economically unfeasible and is damaging to the environment by causing severe fragmentation.

In the proposed project we will set up as a cooperative program between the Israel Nature and National Parks Protection Authority, the Association of Cattle-growers in northern Israel, and the Galilee Technical Center (MIGAL). It will be aimed at developing, testing and deploying various non-lethal techniques that will reduce depredation by wolves. By doing so, not only will a reduction in depredation be achieved, but also cooperation and trust will be restored between the various factions ensuring that no illegal one-sided steps be taken against the wolf population, and contributing to the wolves future survival in northern Israel. In specific, four techniques will be evaluated and deployed with the full cooperation of the cattle-growers: Guarding dogs, electric fencing, olfactory repellents and acoustical deterrents.

Objectives

The immediate objective of this project is to provide a 'green' solution to depredation of cattle by wolves in northern Israel and disseminating this knowledge to cattle growers throughout the region. Achieving this objective will have two outcomes which will have a major impact on the survival and well being of the endangered wolf population in northern Israel. (1) Cattle growers will not become frustrated by the seemingly un-attentive attitude towards the depredation problems and will, therefore, not engage in illegal attempts to poison wolves. (2) Culling wolves to reduce depredation will not be necessary. The project is founded on an, already existing, cooperation agreement between the Cattle-growers' Association, the Galilee Technical Center and the Nature and National Parks Protection Authority. As a consequence, an additional outcome of this project will be the establishment of a permanent connection and working protocol between the cattle growers and conservation organizations.

Methodology

Guarding dogs

The use of dogs by livestock owners became common during the 1970's, when use of many poisons was discontinued (McGrew and Blakesley 1982). Livestock-guarding dogs on U.S. farms and ranches provided substantial reduction or elimination of predation against coyotes (C. latrans) and domestic dogs (Coppinger and Coppinger 1993, Andelt 1992). In all but a few cases, dogs prevented depredation not by killing the predator but by "warning it away" (McGrew and Blakesley 1982), which they do because they are an integral part of the flock. However, many livestock producers still consider guard dogs as a complementary method while relying on other techniques for control (Andelt 1992).

Guard dogs work by being attentive to livestock and driving away intruders (McGrew and Blakesley 1982). Guard dogs are not an immediate solution to a predator control problem because they must be socialized to the animals they protect (Coppinger and Coppinger 1993). One-two years are usually required for a guard dog program to be in place once the need has been identified.

Although the use of guard dogs in North America has focused on reducing depredations by coyotes and is among the most publicly acceptable methods of predator control, their effectiveness against wolves is not well known. Guard dogs and wolves could potentially behave as conspecifics, which would negate any guarding behavior.

Although, wolves are also known to attack and kill domestic dogs (Fritts et al,1994), non-lethal protection of livestock from wolves (Canis Inpus) with guarding dogs (C.familiaris) is a tradition among shepherds in Europe and Asia (Coppinger and Coppinger 1993,) and have been used successfully in Eurasia against wolves. Boitani (1992) noted that sheep in Italy are well protected" against wolves by guarding dogs, although damage does occur. Schmitt (1989) reviewed descriptive literature from France and Italy, relying on work of Coppinger et al. (I 983) and others in the U.S. for technicalinformation. Intraspecific-like social displays between dogs and wolves may alter wolf feeding behavior when dogs are present by delaying the onset o interrupting depredation routines by the wolf. Thus, reducing the efficiency of the wild predator. "Protection" was also achieved because wolves appeared to avoid the dog. None of these reviews reported any directed research on the use of dogs against wolves.

Even though guarding dogs are used in Europe and Asia to protect against wolves, Israeli cattle-growers and wildlife damage control personnel have expressed reservations about guarding dog effectiveness against wolves. Systems of livestock management are different here compared with abroad, where human shepherds and night confinement are common.

In the past year a small-scale experiment in one ranch in Northern Israel using Great Pyrenees dogs in beef cattle herds grazing in the natural pastures was very successful with depredation dropping over 90%. Limitations of expanding this program are the shortage of trained dogs and training cattlemen in dog utilization. In the current proposal we plan to establish breeding and training center for guarding dogs and an extension program for cattleman dog handling is included. The introduction of the Akbash, a Turkish guarding dog, in addition to the Pyrenees began and will also be included by the proposed program.

A survey to select the best cattle farms for guarding dog's management has been conducted; the best ones (about 5 in the first year of the program) will be supplied with four trained dogs, each. A worker, partially supported by the program will provide close advise in dog handling.
 
 

Electric fencing

Fences were used to protect domestic sheep from wolf predation in early Europe (Wade 1982). Potentially, fences are the least controversial technique for controlling livestock losses from wolf predation. Most landowners in the early American colonies are likely to have had fences to retain livestock and some probably constructed antiwolf fences. Tne first record of a fence for controlling wolves was in 1717, when a wooden fence to encircle several towns in the Cape Cod area of Massachusetts was proposed (Young and Goldman 1944). Although it was never built, the proposal testifies to the paranoia toward wolves and livestock depredations in colonial times.

Early in the 20th century, ranchers used woven wire fences to protect small numbers of livestock from wolves, but larger ranges were not usually enclosed (Young and Goldman 1944). Some ranchers in the Southwestern U.S. advocated a wolf-proof fence along the U.S.-Mexico border in the 1920's. The U.S. government experimented with several types of wolf- and coyote-proof fences to reduce depredations on livestock; none were found practical (Young and Goldman 1944, Wade 1982)..

Modern electric fences have successfully excluded coyotes (Connolly,1978), but tests on wolves have not been reported. Most wolf problems occur in marginal areas, where livestock often range freely. Because cattle pastures are usually large and often in rugged country, the assembly and successful operation of an electric fence is difficult and expensive.

In Northern Israel the average size of cattle pastures is 100 ha. A partially successful trial to test the efficiency of electric fencing as a mean to protect a one hundred ha of natural pasture was conducted. In the protected area a herd of calving cows grazed during most of the calving season. During the periods where the electric system was working no wolf attacks were documeted. The only problem was that maintenance was difficult due to the lack of a road running along the fence so the fence had to be checked on foot. The new proposed fences will be erected in pastures surrounded by dirt roads. In other pastures, other protection methods will be used.

Olfactory repellents

After a period of failure during the 1970’s in developing effective chemical repellents to prevent depredation of livestock by predators (USFWS, 1978), their use has once again gained in popularity and acceptance. An important symposium on the subject of animal repellents took place in the USA in 1995, and it summarized all the known work on the subject until then (Denver Wildlife Research Center, 1995). That symposium showed the advantages of using chemical repellents to prevent vertebrate pest damage as long as these criteria could be met:

The chemical repels without causing lasting harmful effects to the wild animal

The chemical is effective in the field (not just in laboratory conditions)

The chemical is benign to the environment

Two types of chemical compounds can repel animals: 1. Compounds that link a food source with induced sickness through a behavioral process called conditioned taste aversion (CTA), also known as food aversion learning (FAL) (Gustavson et al., 1974; Lehner, 1987), and 2. Compounds that repel through unpleasant stimuli of the nervous system (Landa et al., 1995). The first type are properly referred to as aversive agents, while the second type are true sensory repellents.

In the 1970’s sheep growers in the USA began using lithium chloride (an aversive agent) to prevent coyote depredation. Later, this compound was used to protect cattle from wolf depredation in Minnesota (Gustavson, 1982/83). Although lithium chloride itself has no unpleasant flavor, it induces temporary sickness in canids. The predators learnt (through conditioning) to avoid eating livestock. Although CTA seems to be a likely way to reduce depredation without resorting to lethal means, it has a few major disadvantages that have prevented it from being widely used. First, a large number of livestock must be sacrificed to the predators in order for the conditioning to take effect. Second, each generation of predators must re-learn the technique. Third, a large percentage of all the livestock needs to be treated with the CTA compound, in order for the technique to become effective. Research on CTA continues, but it is not widely used.

The use of sensory repellents to reduce vertebrate pest damage has also gained in popularity. Mammals are usually repelled by bitter or spicy compounds (e.g. denatonium derivatives), whereas these do often not bother birds. On the other hand, many birds are repelled by methyl anthranilate, which tastes pleasant to most people.

One compound found to be especially effective in repelling mammals is capsaicin (Lehner, 1987), the active ingredient causing the “hot” taste in peppers of the genus Capsicum (Maga, 1975). This is an olfactory repellent, and therefore does not require direct contact with the delivery agent. Laboratory experiments have shown that even one percent capsaicin applied to their food, can greatly reduce feeding by rats (Mason et al., 1991). In addition, capsaicin-based formulations have been used effectively in Alaska to repel bears from attacking people (Kendall, 1995). Recent field tests in Israel of a new long-lasting, capsaicin-based formulation have shown its effectiveness in keeping wild boar (Sus scrofa) away from sensitive military areas for over 40 days following a single application. In a pilot test against wolves in northern Israel, this same formulation successfully stopped further depredation of cattle in a large range area with a perimeter of about 4 km. Because of the unique slow-release properties of this formulation, it has been deemed to be a useful addition to the non-lethal techniques of depredation prevention available to the cattle farmers in areas of Israel where wolves reside. This formulation meets all three criteria mentioned above.

Actual techniques of application of this formulation involve spraying it onto colorful plastic sheeting that is then attached to the existing barbed wire fences surrounding the cattle range. This reduces costs by utilizing existing structures (unlike electric fencing which requires the addition of grounded fence posts). This technique also introduces a novel item (colorful plastic sheeting) into the field, increasing the probability that the wolves will inspect it, thus getting a “dose” of the hot pepper onto themselves. A third advantage of this technique is that it can also prevent intrusion into the range area by jackals (Canis aureus), a species also known to cause livestock depredations in northern Israel (Yom-Tov et al., 1995).

Acoustic deterrents

“The basic goal of using frightening devices/stimuli is to prevent or alleviate damage by depredating mammals, by reducing their desire to enter or stay in the area where livestock are kept” (Linnell et al., 1996). With the goal of making livestock-rich areas unpleasant places for predators to be (Conover, 1981), an increasing number of studies have used sound to prevent depredation of livestock (Stewart, 1974; Bomford & O’Brien, 1990; Koehler et al., 1990; Linhart et al. 1992). The USDA helped develop a device with sirens and flashing lights that has met with some success against sheep depredation by coyotes (Linhart et al., 1992). Other noise makers have been employed, but the biggest problem with these methods is the process of habituation; after a certain amount of time, the animals tend to ignore the bothersome sounds (Bomford & O’Brien, 1995), unless they are accompanied by a real threat or by actual discomfort.

One approach is to utilize ultrasonic sounds to cause a painful stimulus to the approaching predator. Ultrasound is defined as those sound waves above 20 kHz, the threshold of human hearing. Canids have an auditory system four times as sensitive as that of humans, and they can generally hear sounds from up to 50 kHz (Heffner, 1983; Stewart, 1974). Ultrasonic deterrents work by using sounds at a high decibel level (above 120 dB), but outside the range of human hearing, to cause a painful deterrent (Shumake et al., 1982; Blackshaw et al., 1990). Because loud ultrasound causes real discomfort to the approaching animal, no habituation occurs (as opposed to sirens), and predators stay clear of the area.

An Israeli company, Max Tech, which specializes in military electronic applications, has devised an ultrasonic device that is used to repel domestic dogs. In its civilian form, the device may be useful for repelling canid predators from livestock. Successful field tests of the military version of the device have been conducted. But further development is needed to adjust to technique to the hearing range of wolves while making sure cattle are unaffected. Also, an effort will be made increase its range. This device provides an inexpensive, low-maintenance, non-lethal method that will allow ranchers to keep wolves (and jackals) out of areas where their livestock are kept. It is relatively small, so it can be moved with the cattle from one pasture to another.

Validation structure

We will validate the effectiveness of the various techniques being used in two ways: (1) Monitoring depredation events. (2) Monitoring changes in the space-use patterns of wolves.

Depredation events

Each time a calf is found dead in the field it will be reported directly by the cattlemen to the regional veterinary doctor (from the Israel Veterinary Services) who will come out to the site and determine if the cause of death was predation and what the predator was. In this manner we will be able to determine objectively if the number of depredation events declines after the various protective methods are established. This working protocol has already been established.

Wolf space use patterns

In parallel to the deployment of the various protection techniques, we will track the local wolf population using radio-telemetry techniques. Base line data on the space used patterns of wolves in the region was established in a radio-telemetry tracking project that was begun in 1996 by the Nature and Natural Parks Protection Authority. This study will be continued and expanded. The data will be analyzed using the Kernel Method (Worton 1989) home-range analysis to detect shifts in the utilization distribution before and after the deployment of various protective measures. In addition, because sequential tracking will be used and carried out 5 nights a week, we will be able to determine movement-pattern responses to various protections of individual wolves in real time.

Scientific structure

We will test our findings based on COTE (Control Over Time Experiments). We will use existing data as base-line data on depredation and wolf home ranges ( 'before' data), and compare it with data collected after the various protection methods are implemented ('after' data). In addition, we will implement different techniques in different pastures, in several pastures we will use more than one technique and in several pasture to protection will be used (control). In this manner we will be able to compare between pastures to determine the most effective technique or combination of techniques.

Infrastructure

The project is a based on an already established collaboration between the Nature and National Parks Protection Authority, the Galilee Technological Center and the Cattle-growers Association in the region. Also, the program has the full support of the Israel Cattle Breeders Association and the Israel Ministry of Agriculture. At present all data on depredation events in the region are recorded in a single data bank of the Nature and National Parks Protection Authority. There are regular monthly meetings between the representatives of the cattle growers and the scientists and executives of the Authority. A single person has been appointed to coordinate between the three bodies involved and the various aspects of the program.

Technical description

To achieve the goals of this project the following equipment and materials will be needed.

A 4x4 off-road vehicle for fieldwork concerning all aspects of the program. Most travel expenses listed are to cover the cost of operating this vehicle.

Electric fencing material

Receives and transmitters for radio tracking the wolves

Development of several prototypes of the Acoustical Deterrent machine.

A Global Positioning System receiver to delineate the various pastures on a GIS system.

GIS layers of the region in which the project is being implemented.

A computer and computer software for recording and analyzing the data.

 

 

Risks

The main risk of this project is the possibility that none of the techniques employed will prove useful. If this occurs, there will be increased pressure by the cattle growers to use lethal techniques to reduce depredation. However, preliminary studies have shown that each of the four methods suggested in the proposal has a high potential to produce positive results. Thus, the probability of all approaches failing is exteremely low.

Dissemination of information, potential for reproducing elsewhere, financial sustainability and follow-up.

The knowledge produced by this project will be disseminated in several ways. Locally, progress reports and outcomes of the project will be past on to the cattle-growers through their representatives in the monthly meeting of the personnel involved in the project. A bi-annual report will also be distributed to the cattle growers detailing the techniques, how they were implemented and how effective they were. Nationally, the information will be distributed through the ministries of Agriculture and Environment.

We will set up a home page where the infrastructure of the project, and the techniques and their outcomes will be detailed. In addition, scientific papers will be presented and published in the appropriate congresses and journals (such as Journal of Range Management).

We generally assume that the success of the project will encourage cattle-growers in the country and out-of-the-country to implement these techniques (depending on conditions) on their own and in this manner achieve a reduction in depredation (reduced losses) while increasing community support. In so doing, a status quo may eventually be reached between wolf conservation and the needs of cattle.

The basic framework of this project could be used as a general approach to solving other nature-man conflicts.

Work schedule

There are three basic phases to the program:

A preparation phase in which thground for deploying all the protections is established (such as a dog training facility, producing the first prototype of the acoustic deterrent and building the electric fences). This will take up to 18 months until all methods are operable in the field.

A period of one year (between month 18 and 30) will concentrate on monitoring the impact of all methodologies.

The last six months will be devoted to summarizing and publishing the results and trying to get more cattle growers to deploy these systems. Monitoring will continue at this time, while the project is already being summarized.

 

 
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