By Ryan Trapani
Excerpt from Leonard Lee Rue III from “The Deer of North America” that really shows the importance of HABITAT. I firmly believe that despite all the good intentions of game laws, hunting regulations, etc., it is the change in habitat that has had the most positive outcome on the reemergence of many of our “game species” we take for granted today – turkey, deer, bear, coyote, etc. Despite regulations, many of these species would have made a comeback on their own, as farm abandonment progressed, and energy shifted from domestic animals to “wild animals.” Read on.
Take the hypothetical case of a large piece of virgin forest in the North Country. Deer have expanded their range up to the edge of the forest as farmers opened the land. A few wolves inhabit the forests but do not invade the farmlands because of the concentrated presence of humans on the farms. Suddenly, the huge forest is opened up because of pulp cutting, timbering, or perhaps a forest fire. This forest land is not suitable for farming for any of a number of reasons, such as soil infertility or too short a growing season. If it had been suitable for farming, it would have been cleared sooner. After being opened up by cutting or fire, it is allowed to remain forest land.
Once the climax tree canopy is pierced, allowing sunlight to strike what had been a shaded forest floor, a profusion of berry plants, ferns, mushrooms, and grasses start to grow. These plants will be followed in a couple of years by natural reforestation, by aspen, birch, alder, maples, pines, hemlocks, or cedars, for example. In a short time, this area is superb wildlife habitat, because it produces almost limitless foods of many types, and cover as well.
The deer are quick to respond to this situation and expand their range to fill the niche. There is very little predation at first because the wolves were driven from the area by the presence of the woodcutters and the lack of cover, or by being deprived of both food and cover if the clearing was fire-caused.
The deer herd, unfettered by predators and lunched by an unlimited food and cover support system, explodes. On a high quality, unlimited diet, the does produce more young, more of which are female. The young are larger and healthier from the start and in turn breed earlier, producing even more large, healthy offspring. Within four years, say, the deer will be reaching maximum weight, the bucks will be producing exceptionally large antlers, and the herd population will have maximized so that all available habitat is filled.
Except during the hunting season, humans seldom venture into the area, so there is really little disturbance. The wolves drift back into the areas, drawn by a burgeoning prey species. The deer population is so high that the wolves do not have to go far, nor hunt very hard. In response to the easy living, the wolves, too, have larger litters, with more pups surviving. This increased predation has little effect on the deer population, because the wolves are the apex of the food pyramid and the food and habitat base is broad and solid. And the weather has been benevolent. Mature does carry twins and triplet fawns every spring.
But nothing in nature is static, certainly not habitat. Everything else in the rejuvenated forest land is also growing. Between the sixth and eighth year, the deer population has peaked, although the wolf population has not, because the predator’s cycle always follows the prey’s cycle by a year or two.
By the ninth year, the deer are declining in numbers because they are beginning to encounter food shortages. There is no starvation yet, because the wolf population has now peaked and the predators are depressing the deer population. With food becoming harder to find, the does are not going into the winter in as good condition as before. They are coming into estrus later; there are no triplet fawns; some of the does are bearing a single fawn; fawn mortality is high; and almost none of the female fawns breed at seven months of age.
Food shortages become critical for the deer in the tenth year because the foliage of most of the saplings has grown beyond the deer’s reach. The umbrella effect of the high foliage eliminates most of the understory vegetation. The wolf population is still high because, although the wolves have to travel farther because the deer are fewer, the deer are not as strong and are more easily captured. This is a hard winter for the wolves, but harder for the deer. The winter is extremely cold and windy, and a number of the deer die. By scavenging and taking the starving deer, the wolves have more than enough to eat and produce the same large litters.
The eleventh year repeats the pattern of the tenth. But the wolves travel farther, they expand their territories, and they encounter different wolf packs more often. Strife among the packs results in the death of and number of the wolves.
The deer population reaches an all-time low in the twelfth year, due to lack of food and fairly high predation. The few does that are able to carry a fawn full-term produce mainly bucks, so that the sexual composition of the population is radically altered. The herd is now primarily older deer because most of the young died during the first two hard winters. During a third cold winter; with little food, most of the deer die because the older deer don’t have good enough teeth to cut off the woody old browse, which is all that is available. Their bodies are scavenged and, although the female wolves give birth to smaller litters, scavenging allows them to give birth. But that summer, most of the wolf pups starve because the adult wolves have few deer to hunt. There are few buffer species, because a deer-destroyed forest is almost barren of underbrush, and without underbrush there is little or no wildlife of any type.
Some good came out of all this. With the deer herd only a remnant, some of the vegetation begins to come back along the edges of the ponds, lakes, and old wood roads. It does not recover in the wooded areas because of the shade. The few deer that survived now have access to more food and quickly regain their strength and vigor. The does go into the rutting season in better condition, and the fawns they bear are predominantly female. Even so, the land cannot reach its former high productivity unless the climax habitats again drastically altered by man or fire. The drastically reduced deer herd cannot support a wolf population at all, and those wolves that did not starve migrate to areas with more prey species. The lives of prey and predator are balanced on a seesaw, the fulcrum of which is the habitat.
-Leonard Lee Rue III
The Deer of North America
The purpose of including this excerpt is to demonstrate the relationship between flora, fauna and human influence/impact upon habitat. Humans can benefit flora & fauna by creating diversity, food, and cover in the forest which ultimately influences and creates diversity in flora & fauna. Note the logging disturbance mentioned was not a forest conversion to a non-forest one, but instead a re-shaping of the forest into a new and different one.
