For many pet owners, the discovery of a lifeless bird or mouse left on the doorstep by their pet tabby cat is an all too familiar sight. This in an unpleasant find for most, but other than how to dispose of it, many people give little thought to the dead creature. After all, the family pet occasionally killing wildlife doesn't cause much harm, right?
"Pets have a major impact on wildlife populations," said Jim Hall, Deputy Refuge Manager for the Kenai National Wildlife Refuge.
According to U.S. Fish and Wildlife Service statistics, domestic cats are estimated to have killed more than a billion small mammals and hundreds of millions of birds each year in the U.S.
Although many of these animals killed by pets are pest species like rats and mice, many are not. In addition to squirrels, voles and other small mammals, cats also can prey on song birds visiting neighborhood feeders, ground nesting birds like grouse and even migratory birds which are protected by law.
"Anyone found liable under the Migratory Bird Treaty Act, could be fined up to $15,000," said Hall.
The harm caused by pets killing native wildlife doesn't stop with the species themselves, but also affects the predators and other animals that have come to rely on these species as a stable food source.
"It's a food base that's removed from the food chain," Hall said.
Native predators like falcons, hawks, owls, mink, ermine, marten, fox and even lynx can be affected by this disruption in prey, according to Hall. He pointed out how pets can affect large mammal populations, too.
"Here on the Kenai, predation on caribou calves by loose dogs is a major limiting factor of the lowland herd," he said. Dogs may not always kill the animals directly, but can indirectly cause the death of caribou, as well as moose, in a variety of ways.
Dogs can chase them to exhaustion, leaving them vulnerable to escape from natural predators. Bites from dogs can cause injuries or infections that wild animals may succumb to weeks after the incident.
In winter, dogs can cause animals to be hurt or killed when running across ice or hazardous roadways.
Also, dogs can force animals to flee, burning calories that often are needed to survive the cold weather season.
A variety of diseases and parasites can be transmitted between pets and their wild relatives. Lice showed up in Kenai Peninsula wolves in the early 1980s and spread like wildfire through the wolf population. Lice are not indigenous to Alaska, and many biologists suspect the lice spread to the wolves through contact with dogs.
Hall pointed out that pets interacting with wildlife is a two-way street and sometimes it's the dog or cat that is on the receiving end of harm.
"Interactions with coyotes, wolves and bears can definitely be fatal to pets," he said.
Small mammals like porcupines also can hurt pets severely. Loose pets that return home looking like pin cushions should be taken to a veterinarian since porcupine quills can frequently break during removal and fragments left under the skin will over time work themselves deep into the pet's body tissues where they cause serious infections.
Veterinarians frequently use anesthesia on pets, making removal much less painful, and they often prescribe antibiotics to prevent infections following quill removal.
Pet owners should be aware that the Alaska Department of Fish and Game has a zero-tolerance policy on any dog that chases, attacks or harasses a wild animal in any way. Fish and Game officials are authorized to put down wildlife-harassing dogs.
As the human population on the peninsula continues to grow and encroach into the habitat of wild animals, it no doubt increases the potential for interactions with pets and wildlife. But there is a simple solution keep pets under control.
The best prevention for protecting wildlife from pets, and vice versa, is to keep pets from roaming free.
Dogs should be kept in fenced yards or on leads, and should always be walked on a leash or under direct owner supervision. Cats also should be kept indoors or in fenced or enclosed outdoor runs. Also, keep all pets up-to-date on their vaccines to ensure what they leave behind won't harm wildlife, either.
Joseph Robertia is a reporter for the Peninsula Clarion. He has worked with wildlife and domestic animals for more than 10 years as a veterinary technician, a zoo keeper, and most recently as a zoologist for the Wildlife Conservation Society. He welcomes any pet-related questions or story ideas, but please none of a veterinary nature. Ideas and questions can be sent to his attention by e-mail at clarion@ alaska.net.
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