I sat back and thought a few minutes the other day when I read a story about South Carolina's 2012 deer harvest dropping about 4 percent compared to the 2011 harvest and being more than 30 percent lower than the record 2002 season.

What was most interesting was to think that what's going on with our wildlife today was, perhaps, most influenced by something that happened 25 or 30 years ago.

You won't get a big argument from anyone when you point out that habitat is the single largest driving force in the ups and downs of, say, a deer herd or a turkey flock, and there's little question that the decline in quail populations across the Southeast is directly linked to changes in land-use patterns.

Several years ago, I was interviewing Charles Ruth, the biologist who heads up deer and turkey programs for the S.C. Department of Natural Resources. Ruth said that "South Carolina got into the deer business" in the 1970s and 1980s when much of the state's timberland was forested and replanted in pines.

After an area is clear-cut and replanted, it takes a handful of years before it reaches the stage that biologists call "early successional." That means a lot of little green bushes grow up and provide a tremendous amount of forage and cover for wildlife like deer and turkeys. The forest has no canopy, sunlight can reach the ground, and everything grows. That land essentially becomes what Ruth called "a deer nursery."

That's a great situation, on a large scale, for about 15 years. Then, the trees get big enough to provide a canopy that keeps the sunlight from reaching the forest floor and providing the basis for photosynthesis to take place and plants to grow. At that point and until the land is timbered again, habitat starts to deteriorate and can't support the same number of deer and game birds. Good timber management includes prescribed burns, and thinning opens up the canopy somewhat to provide the kind of ground cover and browse that sustains good populations of all kinds of game.

At some point, however, usually around 25 to 30 years after planting, the pine plantation matures, the habitat is degraded and, until the timber is cut and the whole process starts again, the amount of wildlife the habitat supports is at its lowest ebb. That's when things like food plots and aggressive wildlife management make their greatest difference.

Since about 2005, South Carolina has been on that curve in the cycle where much of the timber planted in the late 1970s and early 1980s is at its most-mature level and can't support nearly the wildlife it could in the 1990s. We can expect deer and turkey harvests to drop somewhat. The cool thing, however, is that when the cycle starts over in the next five or 10 years, things will get better - as long as we keep fields and woods from being replaced by concrete and asphalt. Happy days may be here again. Until then, we wait.