Territories

Not too long ago I was reading about migrating birds. For this particular species, half their year was spent in the desert while the other half was spent high in the mountains.

The author posed the question, "Whose birds are they, the desert folks' or the mountain folks'?"

My instincts tell me these birds don't belong to anyone other than themselves. For many species, the concept of belonging is determined by factors different from those used by modern humans.

I then pondered, what are the criteria of human belonging? I began researching the concept of territoriality, specifically physical territories.

Strictly speaking, territoriality is the behavior of defending a space. There are political territories set by national borders. Ideally everyone within those borders adheres to an agreedupon set of behaviors. These boundaries are protected, usually by individuals in the military.

Searching more locally, I looked at personal territories defined by property borders. Contemplating the concept of human homes, I realized that we are unique from other animals in our definition of space.

While other species defend their territories from conspecifics (same species), it is only humans that eradicate all other species from their home territory. In many American kitchens a can of Raid sits, ready to kill any uninvited living thing. Only houseplants, pets, friends and family members are welcome. Other than that, the house is devoid of other life forms, sometimes even unwanted humans. humans.

How does this behavior differ from territoriality of other species? Territoriality from the perspective of animal behavior is defined as a form of defense for food sources, nest and denning sites, or other resources against other members of the same species (occasionally against animals of different species).

Knowing when to defend

The most apparent difference is that territoriality is related mainly to competition among the same species. Because a wild animal's energy budget is so tight, the time and energy that would be consumed by defending a piece of land against all other species would inevitably lead to demise.

Secondly, territoriality is a behavior dependent on resource availability. It is only costefficient to defend a territory when food availability is predictable. If there is a consistent source of sustenance, animals will defend that source. But in locales where food availability is marginal or seasonal, there is no reason to defend a territory since the animal becomes more nomadic, traveling where the food is. So, like the migrating birds, the concept of permanence is just that— a concept.

Beyond the availability of a food source is the proliferation of that food source. At times when food supply is high, intruder pressure increases as a result of that abundance. In such times, the cost of defending a territory from so many intruders becomes greater than the calories obtained from the food.

On the other end of the spectrum, when food abundance is very low, again the cost of defending a territory even from a single intruder could be so high that death could result. Under the condition of either very high or very low food supply, territories are often abandoned.

Aggression, scent and song

But not all notions of animal territoriality are foreign to humans. As with humans, there are a number of ways in which animals defend their territories. One way is by outright aggression. This can be observed by the hummingbird's hostile behavior around a feeder.

Another form of territoriality can be seen in threat displays. These displays could take on the form of showing colorful feathers, as the ruby-crowned kinglet does, or of raising hackles and baring teeth, as a coyote does.

Scent marking also serves to define territories. Wild felines will rub facial glands on prominent land features to communicate with other felines. Foxes will urinate and defecate to mark boundaries.

Yet another territorial defense is song. Birds will sing their hearts out to declare a suitable territory for nesting females. They will also use these songs to warn away intruding males.

For each of these defenses— aggression, threat displays, scent marking and song—I can think of a corresponding human behavior. Often though, animals are only territorial during breeding season. We even see this phenomenon with a human father-to-be becoming especially protective of his pregnant partner.

Interestingly, it is only a small percentage of animals that are consistently territorial. More often, species avoid aggressive encounters and at times encourage symbiotic relationships with others to enhance their own habitat. The energy consumption of chasing every livingthingou tofi tsspace wouldbeco stlyandulti mately detrimental. I wonder how high a price humans pay for our strict, intolerant and continual territoriality?

Meghan Walla-Murphy can be reached at the following e-mail: mwallamurphy@yahoo.com.