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Apex vs. Mesopredators

Most often, apex predators like mountain lions, bears, and wolves dominate the news. That is because they dominate the food chain - virtually the only thing that hunts these large predators are humans and their own kind. They are larger than life, equipped with sharp teeth, tough hides, strong muscles, and incredible athleticism. Their size, power, and threat to humans are captivating.


But what about the predators with the same set of tools, only in miniature? These animals are more commonly seen, like bobcats and coyotes, and are categorized as mesopredators. Mesopredators can be described as carnivores or omnivores that prey upon other animals, but they are also threatened by apex predators as a source of food or competition for resources. There is not an end-all-be-all definition for this ecosystem role, but they are often medium-sized in stature and occupy the middle or near the top of the food chain.


Bobcat on the move (Lynx rufus)
Bobcat on the move (Lynx rufus)

Southern Arizona is home to many mesopredators, thanks to the incredible diversity that the Sky Islands harbor. Not only do we see bobcats and coyotes, but four species of skunks, the gray fox, and three species of Procyonidae: the ringtail, raccoon, and coati, which all prey on small mammals, birds, amphibians, and reptiles. Mesopredators play a vital role in maintaining prey populations like rodents, and they help stabilize apex predator populations.


Pair of coyotes (Canis latrans)
Pair of coyotes (Canis latrans)

Historically, apex predators like wolves, grizzly bears, and mountain lions were heavily hunted due to fears of predation on livestock and competition with humans for game species. This led to significant declines in their populations across the United States, including Arizona. Government-led predator control programs were established in the 19th and early 20th centuries, and bounties were offered for shooting or poisoning these critical creatures. Bear, wolf, and other predatory pelts were sold for high prices. The insatiable need to kill off carnivores was thoroughly instilled in white colonists of the West. Wolves were labeled as vermin and pests, and many people, even those we view as iconic conservationists like Aldo Leopold, thought it was their duty to kill every last wolf. They pictured forests full of deer, a never-ending supply of food, and hunting trips.


Gray fox (Urocyon cinereoargenteus)
Gray fox (Urocyon cinereoargenteus)

As environmental legislation was first passed in the 1960s and conservationists began understanding population and ecosystem dynamics, large predator populations remained low as human development fragmented habitat and restricted the movement of these predators, who often require large tracts of connected, undisturbed land to survive. Fear and misunderstanding about apex predators continued to lead to targeted killing, even after their legal protection.


This culmination of fear, ignorance, and an unrelenting need to conquer the wilderness over a century isolated apex predator populations and made them highly vulnerable to extirpation. This gap in the food chain led to a spike in prey populations and allowed mesopredators to thrive.


Hog-nosed skunk (Conepatus leuconotus)
Hog-nosed skunk (Conepatus leuconotus)

With the decline of apex predators, mesopredators experienced a release from predation pressure and no longer had to compete with them for prey resources. This allowed their populations to increase, leading to imbalances within the food chain that had cascading effects throughout entire ecosystems. For example, increased predation pressure from mesopredators can impact the populations of smaller prey species, which in turn affects vegetation dynamics and other trophic levels. Additionally, as mesopredator populations increase and prey populations are depleted, individuals must find other sources of food. As curious animals like raccoons, skunks, and coyotes search for their next meal, conflicts with humans may arise, particularly in urban and suburban areas where these animals may come into closer contact with humans.

White-nosed Coati (Nasua narica)
White-nosed Coati (Nasua narica)

A lot has changed within the last five years, let alone the last century. Arizona lost its last grizzly bear in the 1930s, mountain lion populations plummeted, and the Mexican wolf was extirpated from the state altogether. While the grizzly bear will never see the White Mountains again, black bears have maintained a healthy population throughout the state. Mountain lions and even jaguars are expanding back into their historic habitat ranges. The Mexican wolf population is on the rise after a captive breeding program released 11 individuals from a small population in northern Mexico into Arizona and New Mexico in 1998. There are now at least 257 individuals, and the population has shown continuous growth over the past eight years.


Reinstating the role that these large predators play will help balance food webs, increase biodiversity, and keep mesopredators and prey populations in check. In turn, the entire ecosystem will thrive, and people will have the opportunity to view the landscape as it once was.

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