Orphaned Cooper's hawks growing up
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On the list of predatory species, we might tend to look for things that might eat us, given the chance. Being on the top of the food chain here in modern North America, we don't have many animals that qualify as predators of humans. Some species of bears and mountain lions are certainly capable of preying on us if we invade their territory, but on the whole, we have little to fear from native animals if we are
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knowledgeable of their behavior and respect their habitats. Predators will only attack another animal under two circumstances: if they feel threatened, or if they are hungry. In the second case, they will also have to consider the animal to be something that is appropriate for them to eat. Predators have a certain hardwiring in their brains called a specific target image (STI) which tells them what size and shape things are on the grocery list. Unless compelled by extreme hunger or other artifact, this defines what's on the menu. If you go shopping after you've had breakfast, chances are you will purchase what you need. If, however, you skip your morning meal and go to the store with your stomach growling before lunch, you might buy all sorts of items that were not on the list. (Not a good plan if you're on a diet!) A great horned owl will normally be hunting things like squirrels and skunks, some of their favorite foods. But if they miss a few meals due to weather and/or injury, the STI begins to expand and they will hunt and kill things like raccoons and badgers, which are generally outside of their normal prey inventory. Nature teaches animals what they are supposed to eat. It remains a true fact that in the history of this country, there is no record of a wolf ever attacking a healthy adult human being.
One might suppose that the populations of predators and their prey would cycle up and down reactively, with the prey species declining as the predators increase, and vice-versa. Surprisingly, this is usually not the case in nature. As long as the two groups have co-evolved in the same ecosystem, their populations will remain more or less in equilibrium as long as no outside force intervenes. If a new disease depletes the prey base, the number of predators will also fall off until a new balance is reached. Should the population of the predators drop for some reason, the prey population will spike until the carrying capacity of the territory is exceeded or the number of predators rebounds and again equilibrium is attained. Adaptation and the constant pressure of evolution affect both sides of the struggle. As soon as a predator develops a new successful hunting technique, their target will soon adapt by learning a new way to avoid the new weapon used by the hunter. By the same token, if the prey develops a new strategy or tool, the predator will also adapt some new skill to offset the defense and thereby regain the balance. It's been this way for ages.
And it's not all one-sided, with the predator merely living off the prey. Predation will normally augment the health of the prey species by culling the sick and genetically inferior and thereby add to their success in rebounding. This is why when you put out a bird feeder, you should not be alarmed when the predatory birds arrive to stalk your songbirds. You rang the dinner bell and you are in fact feeding all of the birds, not just the ones that eat your seeds, but also the ones that eat the ones that eat your seeds. For every day a Cooper's hawk or sharp-shinned hawk lives, a towhee, goldfinch, or some other little bird will die. But that's the way it works and that's the way it's supposed to work. And the benefits of this arrangement are healthy flocks, continued diversity, and a deep gene pool for future generations. A predatory species will never kill off all of their prey, thus causing their own numbers to starve and die out. Nature will not allow this to occur, at least without a push from an external force.
We, as a species, sometimes provide that external force. In our wisdom (read: arrogance or hubris), we have tilted the balance of nature in many ways. The number of large mammalian predators has been decimated by human activity, both direct and indirect. We actively exterminated wolves, bears, mountain lions, and anything else we deemed a threat to ourselves and to our activities, to the point that very few of these large animals are left in the wild. The result is that the balance of nature has been upset. In certain areas, their prey are now overpopulating former territories, and in others, due to the lack of beneficial effects of predation, some species are disappearing. We are exercising our position as top predator in out-competing other predatory species for commercial profit in the oceans and the prairies to the point that entire ecosystems are being driven to the brink of extinction. Locally, people generate trash, allow household pets unsupervised access to open areas, and in some cases actively feed predators such as coyotes. This encourages overpopulation beyond the natural carrying capacity of the land and promotes less fear on their part. We should not be overly surprised when these normally shy creatures become bold and aggressive in our presence. The lines between predator and prey have been blurred by our own ignorance and inappropriate actions.
So here is where acting locally can be one of the answers. By the rescue, rehabilitation, and release of animals injured, orphaned, or endangered through contact with people, Liberty Wildlife is continuing in its efforts to nurture the nature of Arizona. And by educating the public through school presentations and public awareness displays, we are hopefully mitigating adverse human impact on the environment and thereby helping to Keep the Balance.
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