By Ross Hall
In 1976 sheep farms in Pictou County were losing sheep to an unknown predator. Kill sites were often far apart and not typical of bear. The trapping and shooting of two coyotes in 1977 confirmed that the coyote had arrived in Nova Scotia. By 1990, the coyote population had expanded to all parts of the province and most sheep producers have felt the anguish of finding wounded and dead sheep in their pastures.
It is a fact that the coyote, Canis latrans , is here to stay, and there is no quick fix for the protection of sheep or for the removal of the coyote. This fact sheet examines the difficult task of protecting sheep from coyotes. Recommendations are made based on experiences learned in other jurisdictions of North America and on the experiences of Nova Scotia sheep producers. Many sheep owners in central Nova Scotia were interviewed and their advice and experiences were incorporated into this fact sheet.
Contrary to popular rumor, coyotes were not introduced to Nova Scotia. With habitat changes in North America, such as land clearing, railroad right-of-ways, etc., the prairie coyote in the late 1800s began a range expansion that reached Nova Scotia in 1976. We probably had a few coyotes prior to 1976, but people assumed sightings to be of dogs. Prince Edward Island and Newfoundland now have coyotes
The eastern coyote is 20 per cent larger than his western counterpart, and has some color differences. Geneticists suggest that this is at least partly a result of cross-breeding with a southern race of a timber wolf, or possibly it is simply natural selection for larger animals in the east.
Coyote reproduction is not too different from that of domestic dogs. Coyotes, however, breed only once per year in February or March and five to seven pups are born in April or May. Pups are whelped in dens, often dug into south-facing slopes.
An adult coyote pair selects and defends a territory. Here they find food and raise their young. Territory size varies, but 15-20 square miles (40-50 km² ) is an average size. Pups stay with the adults into the fall or winter. There are also unmated adults, known as transients or nomads. Their relationship to, or tolerance by, resident coyotes is not well understood.
Most studies of the eastern coyote reveal that snowshoe hare and white-tailed deer make up the bulk of their diet along with small birds and mammals at much lower proportions. Berries, such as blueberries, are eaten heavily when in season. Carrion, both wildlife and domestic, is eaten readily. Sheep can become the favorite prey of coyotes when the opportunity presents itself.
Coyotes usually bite the throat of a sheep, and coyote predation is recognized by the hemorrhage and tooth punctures. Internal organs such as the heart and liver are accessed through the abdomen and eaten first.
Further information on coyote biology and occurrence in Nova Scotia is available in a NS Conservation article "The Eastern Coyote in Nova Scotia."
Without prevention, sheep losses can become so severe that a sheep farm cannot continue financially. Understandably the sheep grower does not want to invest money in protective methods that do not work. Nor are profit margins sufficient to afford much investment.
The following material contains advice on methods that help to prevent coyote predation. Some are more expensive and some more effective than others. Ultimately sheep farmers must examine their own situation and choose a course of action. A combination of protective methods may prove the most effective.
Electric fences are the most expensive, but have shown the most consistency in protecting sheep from coyotes. There is considerable evidence that properly constructed electric fences can reduce or eliminate coyote predation on sheep.
Eric Hutchings, regional supervisor of problem wildlife, Alberta Agriculture, states "Almost all of our producers who have constructed proper electric fences are satisfied with the results. The handful of unsatisfied have usually neglected quality or design standards or encountered an extraordinary coyote which must be removed." Other evidence can be found in a study by the Fish and Wildlife Service in Denver, Colorado. They summarized sheep losses on 14 farms before and after electric fences were built. Before electric fencing, over 271 months and 27 lambing seasons, 1,064 sheep were lost. After fencing, over 228 months and 22 lambing seasons 52 sheep were lost. This is more than a 90% reduction in predation.
In 1990, 31 sheep farms in Cumberland and Colchester counties were visited by Natural Resources staff and a questionnaire completed regarding the history of coyote predation and their methods used to protect sheep. Additionally, 21 farms were visited in Pictou County and six farms in Cape Breton County. From the questionnaire an analysis was made comparing sheep losses among farms that had (1) no electric fencing (2) poor electric fencing, and (3) fair-to-good electric fencing. Electric fences that were rated as poor had combinations of problems such as low voltage, lengths of the boundary with no electric fence, and other design and maintenance problems. Many of these fences were built to keep cattle or sheep in, but not designed as predator fences. Fair-to-good fences were thought capable of deterring coyotes. Predation data is examined for years 1986 to 1990. One farm year is one calendar year in which lambs are born and raised for market.
|Fence Type||Total Number Farm Years||Total Number Sheep Loss||Sheep Loss Per Year|
Factors such as nighttime confinement, use of guard animals, and other husbandry methods influenced these results, but it is apparent that good electric fences protect sheep from coyotes.
Figure 1 illustrates an electric fence design used in Nova Scotia to deter coyotes. Coyotes prefer to go under or through fences rather than over them. On farms with page wire fencing, it is amazing to observe the effort coyotes make to dig under the fence rather than jump over. The coyote perceives page wire as a physical barrier that it cannot easily penetrate. When it encounters an electric fence with horizontal wires, a naive coyote assumes it can easily step through.
Knowing the tendency for coyotes to not jump a fence, a five-wire design is probably sufficient for most coyotes in Nova Scotia. An electric fence with a bottom, grounded wire strung very close to the ground surface is probably the wisest design. The close fit to the ground will encourage the coyote to step up between the ground wire and the next live wire.
Construction of electric fences to protect sheep necessitates modern-day, high-impedance fencers and high-tensile wire. The fence must produce enough voltage to overcome the insulation resistance of a coyote's long hair and hide. A minimum charge of 2000 volts is required, but 4000-5000 volts are much better. The pain should be sufficient that the coyote will not investigate other ways to get through the fence.
The details of high-tensile wire fence construction are not described here, but interested sheep producers are encouraged to seek the advice of knowledgeable persons. Build the fence properly the first time. Prepare a level and straight fenceline. Do not neglect proper grounding or annual maintenance.
Figure 1 - Electric fence design to protect sheep from coyotes
Electrified Conventional Sheep Fence
The construction of new fences with page wire, with the exception of lambing or catching corrals, is not recommended. Electric fencing is less expensive and provides better protection from coyotes.
Electric wire can be added to existing page wire fences. The foremost location for this wire is offset from the outside bottom to prevent coyotes from digging under the fence. Heavy brush growth often around the outside of older fences and uneven ground can make this idea difficult. Secondly, electric wire can be added to the top of the page wire fence to discourage coyotes jumping over.
If it is impossible to electrify a gate, then at least install a board or rock sill under the gate to prevent entrance by the coyote under the gate.
Guard dogs are an ancient form of sheep protection developed over centuries in Europe and Asia. The Komondor (Hungary), Great Pyrenees (France and Spain), Akbash (Turkey), Maremma (Italy), Shar Planinetz (Yugoslavia), and Anatolian shephard (Turkey) are the more common breeds.
The guarding dog concept involves a dog that stays with sheep without harming them and aggressively repels predators. The dog chooses to remain with sheep because it has been reared with them since it was a puppy. Its protective behavior is largely instinctive, and there is relatively little formal training required other than timely correction of undesirable behaviors (e.g., chewing on ears, over playfulness, and excessive wandering). The guarding dog is not a herding dog but rather a full-time member of the flock. Success of the dog is a result of a quality genetic background with an emphasis on proper rearing. Because of their independent nature, training for these dogs is limited mostly to "no" and "come" commands.
An ideal guard dog is intelligent, alert, and confident. It will investigate and aggressively confront intruders; but, above all, the dog must be attentive to sheep and not harm them.
To form a bond between dog and sheep, a pup is placed in a pen with three to six lambs when it is seven to eight weeks of age. The emphasis is on the dog-to-sheep association. The dog-to-human socialization should be minimized. After the initial socialization period, when the pup is at least 16 weeks old, it and its companion sheep can be put into a larger area. The dog should be encouraged to stay with the sheep and not allowed to hang around the house, children, or areas where sheep are not present. The dog should be treated as a working animal, not a pet.
Research on guard dogs has occurred primarily at two locations, Hampshire College's New England Farm Center in Amherst, Massachusetts, and the U.S. Sheep Experiment Station, U.S. Department of Agriculture, Dubois, Idaho. People interested in guard dogs should read the booklet Livestock Guarding Dogs: Protection Sheep from Predators, Agriculture Information Bulletin Number 588, published in 1990 by the United States Department of Agriculture. Hands -on experience is also a great teacher and it would be wise to seek the advice of sheep growers in Nova Scotia who use guard dogs. Sheep producers should consider that the initial cost of a dog might exceed $400.00 plus annual maintenance costs in the vicinity of $300.00. Dogs have a working life of about 10 years, although there is a reasonable chance that the dog will die prematurely. Nevertheless, the experience in the United States is that over 80 per cent of producers considered guard dogs an economic asset. To some producers, the peace of mind of knowing a dog is on duty 24 hours per day is a significant benefit.
Two producers in Cumberland County with working guard dogs said their dogs patrolled extensively at night and were strong supporters of the guard dog concept. Other Cumberland producers had acquired pups.
The guard dog by itself is not the complete answer to coyote predation problems. The two Cumberland County producers also used electric fences. One farm has a common boundary with a neighbor that has no electric fence. The other farmer admitted neglecting maintenance. Perhaps these farms get away with some fence faults because of the combination of methods.
Donkeys are gaining popularity as protectors of sheep. This popularity may be based in part on the notion that little more than purchasing an animal and dumping it in a pasture is involved. Donkeys have an inherent dislike for dogs and presumably coyotes. Donkeys will bray, bare teeth, and make running attacks, kicking and biting. Reported success of donkeys for predator control appears highly variable. A Texas survey reports some owners have success but at least as many do not. Sheep growers in Central Nova Scotia who have donkeys have divided opinions on their effectiveness. Donkeys can cost more to buy than guard dogs.
On the plus side, donkeys have a longer life span and are cheaper to feed than guard dogs. Donkeys are less apt to be injured by foot-hold traps and snares set for coyote control.
Advice from United States studies are:
For sheep producers unable to afford protection methods such as proper electric fencing or guard animals, nighttime confinement is the only choice left.
At many of the farms visited, various degrees of nighttime confinement were practiced. Sheep often move by themselves toward barnyards at night. If old barns or sheds are present, sheep will bed beside or inside them particularly in wet, windy weather. On many farms here sheep spend nights in or near such structures, there is reduced predation. Surprisingly, some farms have had no predation.
Farmers also confine sheep when a series of coyote attacks is occurring. This usually involves enclosing the sheep within a corral or building, while an effort is made to trap offending coyotes. When there is no nighttime access, a coyote will sometimes kill during daylight. Stragglers that are not confined often become victims. Nighttime confinement has drawbacks. Complaints about nighttime confinement include the extra time involved, parasites, manure concentration, and loss of grazing time. Many farmers regularly give medication to control parasites.
If predation losses are heavy, with no alternative protection methods, there is little choice but to use nighttime confinement. Nighttime confinement is a regular practice used in many prairie states such as Kansas. Predation is further lessened by using floodlights.
Where it is impractical and too expensive to put up electric fencing around the whole farm, a compromise and recommendation is to protect at least one small pasture. Rather than putting sheep into a building, sheep can be placed into the security pasture at night, especially when a coyote has recently killed sheep.
Common sense suggests that, if coyotes find dead livestock near farms, they will visit these farms more frequently and the potential for predation is increased. Whether carrion feeding by coyotes leads to predation or whether some individual coyotes are more inclined to kill sheep than others, is not well understood. Most sheep growers agree it is wise not to encourage coyotes by leaving dead livestock in or near pastures.
It is important to remove those coyotes that are actually killing sheep. Removal requires skill and time and is only a short-term solution. Killing coyotes is not a long-term solution to protecting sheep.
Obviously early detection of coyote predation on the farm is important. Look for dead, injured, or nervous sheep. Check the efficiency of electric fences and the activities of guard animals with sheep. Look for coyote signs. Vigilance is important.
Please contact your local Department of Natural Resources and Renewables office for additional information.