Habitat

Nature Notes by Dr. Frank Lang

We hear much about habitat these days. Loss of habitat endangers natural salmon runs in the Columbia River. Many acres of ancient forest are set aside as habitat for the remaining populations of spotted owls and for 100 other vertebrates and 1,500 invertebrates found in the same habitat.

Besides commercially important forest trees, there are other plants and fungi that depend on old growth forest habitat. Nitrogen-fixing epiphytes and mycorrhizal fungi depend on old growth, and old growth depend on them.

After 50 years and more of competing with humans in the Pacific northwest, nature is the big loser. The loss of habitat is clearly evident and makes daily news. This precious habitat is the immediate environment in which an organism lives and includes shelter, food, water and breeding sites. Water is the critical substance and most strongly influences the survival and distribution of organisms. Nourishment also must be available in the habitat on a sustainable basis. If water or nourishment change, so does the habitat and so go the organisms. They leave if they can, die if they can’t. Loss of enough critical habitat may lead to loss of the entire species. The loss is forever, and forever is a long time.

Besides water and nourishment, a suitable breeding environment that allows courting and mating activities is essential. The habitat must support the young to adulthood. Loss of this habitat feature is troubling salmon and the spotted owl.

Humans reduce natural habitats directly by logging, water diversion, plowing for agriculture, and building and maintaining our artificial habitats. We also reduce natural habitats indirectly by polluting land, air and water. Even if there is space available, it may be uninhabitable.

We worry mostly about wildlife habitat. For most that means game animals. Game managers want to maintain enough proper habitat to keep high numbers of game fish, birds and mammals for sportsmen, often at the expense of other natural values. A case in point is the destruction of native vegetation and vernal pool habitat on the Agate Desert by the Oregon State Department of Fish and Wildlife. They plow and plant annual cereals to feed their flightless pheasants.

Wildlife means all the wild things, including dickey birds and plants. A primary reason for the establishment of the Lower Table Rock and Agate Desert Preserves by The Nature Conservancy is to protect sensitive plant habitats. Animals that use the habitat are protected as well.

We now realize that more than space is necessary to maintain a stable population. Mere survival is inadequate. Organisms must survive and reproduce. Offspring are the future. They are the parents of the next generation, they may serve as food for other organisms, they may die of natural causes. Heat and cold, rain and drought, flood and fire, disease and famine all take their toll. To survive, the habitat must provide more than space. Long-term survival depends on intact functioning ecosystems, not an acre here or there. It must provide all these elements to avoid catastrophe.

The hard question is, who has the rights or prior rights to the so-called spaces of nature that serve as habitat? Humans, or the creatures present at our creation?

— Dr. Frank Lang

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