Everyone seems to think of the coyotes as a nuisance. They attack pets, livestock, and on some occassions, even people. The opportunistic coyote has, across the centuries since the first European landings, spread itself from its origin in central U.S. and northern Mexico to span across all U.S. States (bar Hawaii) and from Panama to Canadian tundra. But why have they been so successful in their expansion? And why are they so troubling for humans? Are they damaging to the ecosystems they invade?
Unlike other predators, coyotes are opportunistic feeders. They will hunt and eat large animals like deer and elk, they will also eat birds, rodents, and other small animals, insects, and even fruits and berries. Studies have shown that up to 40% of their diet might consist of plant matter like flowers, grasses, fruits and seeds. Coyotes won’t mind scavenging from trash cans and leftover carcasses either. Their lack of pickiness and ability to adapt to situations is what allows them to spread so far and wide, including in urban situations. Coyotes will fit in anywhere they can find a food source. A testament to their adaptiveness is their ability to be diurnal or nocturnal. But there are other reasons for their success, too.
Their main predator, the wolf, has greatly declined in populations across the United States due to habitat destruction and over-hunting. Wolves would kill coyotes on sight, but with no wolves around, coyotes have much less contest. Coyotes will kill foxes as well, to further deplete of competition.
Coyote hunting is very legal, as most places want to keep the coyote population under check. In 2012, North Carolina even allowed night hunting of coyote because day hunting had only encouraged them to come out at night. Some of the reason coyotes are becoming more problematic for people is their decreasing fear of humans. A lack of coyote harassment and coyote feeding will reduce a fear of humans and make coyotes more likely to attack. Although attacks on humans are still rare (about 150 cases in California found in the last 30 years), pets left out are often in danger of territory conflict with a coyote. At one Orange County California hospital, around 3-5 pets (mostly dogs, because cats aren’t likely to survive an attack) are brought in every week due to coyote attack. Around 60% of livestock attacks are attributed to coyotes. Although coyotes are less likely to attack livestock than an individual wolf, coyotes are far more widespread.
As mentioned before, coyotes will often kill foxes and sometimes may take the place of the apex predator in some ecosystems by forcing foxes to move out, which may have an affect on the ecosystem. In one instance, it was found that in one Southern California study that there is a positive correlation between coyote and scrub bird populations. It is possible that the elimination of smaller predators, such as foxes, allowed more scrub birds to survive. This phenomena has also been found with ducks, songbirds, and partridges in Maine. An absence of coyotes will allow more raccoons and foxes to prey more upon birds.
Another effect coyotes may have on ecosystems is an increase in scavengers, as coyotes will often only partially consume their prey.
Although coyotes can pose a risk to the human lifestyle, they are also an important part of the ecosystem, especially when they are the apex predator. They keep deer and rat population in check, which can prevent the over-prevalence of Lyme disease as well as help avoid rat infestations.