Dog Predation - Description
Domestic dogs can be a serious problem where they are permitted to run at large, particularly near urban areas. True feral dogs and coydogs (coyote-dog hybrids) are also a problem but are far less common.
Domestic dogs do not normally kill for food and their attacks usually lead to indiscriminate mutilation of prey. When they do feed, they tend to leave torn, ragged tissue and splintered bones much like coyotes do.
As a rule, domestic dogs feed very little on their prey. Some individual dogs, including pets, have the instinctive ability to kill effectively, whether or not they feed and some become adept through repeated killing. True feral dogs are more likely to kill for food. Feral dogs and coydogs are also more likely to kill in a manner similar to coyotes, possibly as a result of experience in killing for food.
Both domestic and feral dogs often range in packs and do extensive damage once they begin to attack livestock. Dog packs often harass livestock and persist in chasing injured animals, often for several hours. Careful searching where this occurs often reveals many attack sites with tracks, hair or wool and pieces of skin widely scattered. Fences damaged by livestock attempting to escape, exhaustion, injuries, weight loss, loss of young and abortion are some common consequences of such attacks. Sheep and goats are especially vulnerable. They may drown in streams or reservoirs while trying to escape, or they may "pile up" and suffocate in fence corners, gullies and sheds. Many more may be injured or killed in this manner than from dog bites.
Livestock proximity to urban areas, limited enforcement of leash laws and tagging regulations and estrous female dogs at large are major factors that encourage dog damage problems. Because dogs vary in size and cause diverse injuries, size and spacing between the canine teeth are less useful for confirming the species responsible. Tooth punctures often are not clear where skin and muscle are torn on prey animals.
Dog tracks are also highly variable because of size and weight differences. However, dog tracks are typically more round and show more prominent nail marks than coyote tracks and are larger than fox tracks. In contrast to coyote tracks, a dog's rear tracks normally are slightly to one side of the front tracks. Also, canine tracks made at the same time and location that vary widely in size suggest dog predation, especially near urban areas where stray dogs may range.
Hog Predation - Description
In some areas, domestic or wild hogs (Russian boar, domestic hogs gone wild, and their crosses) prey on poultry and livestock. This occurs more often during droughts or other periods when mast (acorns, etc.) and other foods are scarce. Hogs will also feed readily on carrion but some hogs become highly efficient predators. Hog predation on livestock usually occurs on lambing or calving grounds, perhaps partially because of the prevalence of afterbirth. Occasionally, adult animals giving birth are fed upon and killed by hogs.
Young and small animals are often entirely consumed by hogs and the only evidence may be tracks and blood where feeding occurred. Missing young and their mothers with full udders may indicate such predation, particularly where this is frequent and no other causes for loss can be found.
Hogs feed on carcasses much like bears do although they are not as proficient in skinning them out. They may consume some parts that bears do not, such as the rumen and its contents. Since hogs commonly root up soil and vegetation their presence is usually evident and their tracks are distinctive
Evaluating Predation by Coyotes
In attacks on adult sheep and goats, coyotes typically bite the throat just behind the jaw and below the ear, although repeated bites made while shifting their hold may obscure the initial tooth punctures. Death commonly results from suffocation and shock; blood loss is usually a secondary cause of death. On small prey such as young lambs and kids, coyotes may kill by biting the head, neck or back, causing massive tissue and bone damage.