By Regina Bailey
What Are Endangered Species?
Rare, endangered, or threatened plants and animals are elements of our natural heritage that are declining rapidly or are on the verge of vanishing. They are plants and animals that exist in small numbers that may be lost forever if we do not take quick action to stop their decline. If we cherish these species, like we do other rare and beautiful objects, these living organisms become treasures of the highest magnitude.
Why Preserve Endangered Plants and Animals?
Preservation of plants and animals is important, not only because many of these species are beautiful, or can provide economic benefits for us in the future, but because they already provide us many valuable services. These organisms clean air, regulate our weather and water conditions, provide control for crop pests and diseases, and offer a vast genetic "library" from which we can withdraw many useful items.
Extinction of a species could potentially mean the loss of a cure for cancer, a new antibiotic drug, or a disease-resistant strain of wheat. Each living plant or animal may have values yet undiscovered. Scientists estimate there are thirty to forty million species on earth. Many of these species are represented by dozens of genetically distinct populations. We know very little about most species; less than two million are even described. Oftentimes, we do not even know when a plant or animal becomes extinct. Game animals and a few insects are watched and studied. Other species need attention too. Perhaps in them may be found a cure for the common cold or a new organism that will prevent millions of dollars of loss to farmers in their constant fight against crop diseases.
There are many examples of a species' value to society. An antibiotic was discovered in the soils of the threatened New Jersey Pine Barrens Natural Area. A species of perennial corn was found in Mexico; it is resistant to several diseases of corn. An insect was discovered that when frightened produces an excellent insect-repelling chemical.
Why Have Species Become Endangered?
Loss of habitat or the "native home" of a plant or animal is usually the most important cause of endangerment. Nearly all plants and animals require food, water, and shelter to survive, just as humans do. Humans are highly adaptable, however, and can produce or gather a wide variety of foods, store water, and create their own shelter from raw material or carry it on their backs in the form of clothing or tents. Other organisms cannot.
Some plants and animals are highly specialized in their habitat requirements. A specialized animal in North Dakota is the piping plover, a small shorebird which nests only on bare sand or gravel on islands of rivers or shorelines of alkali lakes. Such animals are much more likely to become endangered through habitat loss than a generalist like the mourning dove, which nests successfully on the ground or in trees in the country or city.
Some animals are dependent on more than one habitat type and need a variety of habitats near each other to survive. For example, many waterfowl depend on upland habitats for nest sites, and nearby wetlands for food supplies for themselves and their broods.
It must be emphasized that habitat does not have to be completely eliminated to lose its usefulness to an organism. For example, the removal of dead trees from a forest may leave the forest relatively intact, but eliminate certain woodpeckers that depend on dead trees for nest cavities.
The most serious habitat loss totally changes the habitat and renders it unfit for most of its original resident organisms. In some areas, the greatest changes come from plowing native grasslands, draining wetlands, and constructing flood-control reservoirs.
Direct exploitation of many animals and some plants took place before conservation laws were enacted. In some places, exploitation was usually for human food or furs. Some animals, such as Audubon's sheep, were hunted to extinction. Others such as the grizzly bear, maintain remnant populations elsewhere.
The frequent presence of man and his machines may cause some animals to abandon an area, even if the habitat is not harmed. Some large raptors, like the golden eagle, fall into this category. Disturbance during the critical nesting period is especially harmful. Disturbance combined with exploitation is even worse.
What Are The Solutions?
Habitat protection is the key to protecting our rare, threatened, and endangered species. A species cannot survive without a home. Our first priority in protecting a species is to ensure its habitat remains intact.
Habitat protection can be done in a variety of ways. Before we can protect a plant's or animal's habitat, we need to know where this habitat is found. The first step, then is to identify where these vanishing species are found. This is being accomplished today by state and federal agencies and conservation organizations.
Second to identification is planning for protection and management. How can the species and its habitat be best protected, and once protected, how can we make sure the species continues healthy in its protected home? Each species and habitat is different and must be planned on a case-by-case basis. A few protection and management efforts have proven effective for several species, however.
Endangered Species List
Legislation was passed to protect the most endangered species in the United States. These special species cannot be destroyed nor can their habitat be eliminated. They are marked in the endangered species list by an *. Several federal and state agencies are beginning to manage threatened and endangered species on public lands. Recognition of private landowners who have voluntarily agreed to protect rare plants and animals is underway. All these efforts need to continue and be expanded to keep our natural heritage alive.