Management Practices Can Influence Predation
by Anita O’Brien, OMAF Livestock Technology, Kemptville
Livestock management practices can help to minimize the risk of predation. Many producers use one or more of the following: regular inspection of the sheep flock, prompt removal and disposal of dead stock, using lighted corrals, lambing in the barn, and perhaps confinement at night.
These practices may not be practical for all producers. For example, it would be extremely difficult to confine a flock of 500 pasture lambing ewes each night. Greater losses would be likely from mismothering, and increased exposure to diseases such as coccidiosis and internal parasites.
For managing predation, a variety of methods must be available; one method will not be effective for every producer. Most successful predator control programs use an integrated approach – combining good husbandry with effective control methods.
Prevention cannot be stressed enough, because after predators kill once they are more likely to return and kill again. If predators have started killing sheep, it is important to stop the killing as quickly as possible. Although many of the following relationships are not clearly defined, it is important to understand the relationship between predisposing factors and actual or perceived losses to predators.
Coyote Behaviour
It is becoming an accepted fact that coyotes will tend to kill, and eat (as adults) what they were taught to kill and eat (as pups). Parker, in his book, The Eastern Coyote, The Story of its Success refers to a number of Canadian studies that strongly support this observation. Coyotes tend to kill animals that are easily caught (least amount of energy expended for maximum gain). As well, coyotes are opportunistic, meaning they will kill prey if the opportunity presents itself, not necessarily just when they are actively hunting. The same holds true for the type of prey.
A typical pair of mated coyotes in agriculture land in Ontario will have a home range of approximately 10 km2 during the gestation period, to over 30 km2 during nursing in May and June. Obviously, their home range will take them through many farms, some with livestock, others not, all with differing livestock husbandry practices. Conditions that lead to coyotes killing livestock on one of those farms put all farms in their home range at risk to predation.
Lack of Normal Food Supply
When normal food sources are scarce, predators will investigate other potential food sources. Livestock fit that category. Once predation starts, producers must be prepared to implement removal options to prevent further kills.
Previous Predation History
Farms where predation has been a problem in previous years tend to have repeat occurrences of predation each year, particularly if no predator removal program has been implemented.
Season and Location of Lambing
Highest predation typically occurs from late spring through September-October due to high feed requirements of raising pups. Lambs born on pasture are more likely to be at high risk to predation than older lambs or mature sheep. On the other hand, winter born lambs, turned out to pasture, may be as much at risk since they are not as alert or suspicious of humans or strange animals as those born on pasture are.
Deadstock Disposal
An Alberta study indicated that predator losses were lower on farms where deadstock were promptly removed and disposed of, than on farms where deadstock were left about.
Human Presence
Frequent checking of flocks can discourage predation from starting. As well, periodically changing when the flock is checked can help to deter coyotes from attempting kills.
Fencing
Coyotes have no problem getting through most net wire fences in Ontario. Traditional net wire fences, with openings of 15 cm by 30 cm (6 inches by 12 inches) allow coyotes easy access to pastured livestock. Modifications with one or two electrified wires added to the outside of the fence, and offset 10 to 15 cm (4 to 6 inches) from the fence and 15 to 20 cm (6 to 8 inches) from the ground, can discourage coyotes from entering the pasture. If existing fences are in good repair, modifications to the fence, rather than total replacement should be considered. If perimeter fences need replacing, producers should consider using page wire with smaller openings, and vertical stays 15 cm (6 inches) apart. See OMAF Factsheet 02-053: Fencing Options in Predator Control.
Livestock Guarding Animals
Dogs, donkeys and llamas are all being used successfully to deter and reduce predation of livestock. Producers must assess which type is most suitable for their particular situation.
Record-keeping
Keeping track of losses can be very beneficial in eventual control or removal of the problem predator. They help to identify loss patterns and-high risk pastures, as well as predict when predation is likely to occur.
Corrals and Night Confinement
Although this may be a practical option for small flocks, or flocks of dry ewes that lambed during the winter, it is not a feasible option for large, commercial flocks that have young lambs with them on pasture.
Novelties
Things like bells on a number of sheep in the flock; aluminum pie plates hung around the perimeter of the pasture, playing the radio, etc. can discourage coyotes from preying on flocks. Anything that causes an irregular sound or reflection can be effective. Again, these sorts of things may be suitable to some producers and not others. Each individual situation must be assessed as to what is most suitable.
References
Parker, G. 1995. Eastern Coyote, The Story of Its Success. Nimbus Publishing
Coyote Predation of Livestock. 1998. Alberta Agriculture