Virginians are fortunate to share their home with a wide diversity of wildlife. Over 10,000 species of birds, mammals, fish, reptiles, amphibians, and different classes of invertebrates may be found from the depths of the Atlantic Ocean to Virginia's highest mountaintop, Mt. Rogers. Regardless of whether a species flies, swims, or crawls, it must have a healthy habitat, or home, to thrive.
Habitat is more than just the space an animal occupies. Within that space are food, water, and shelter, arranged so that the animal can travel with minimal exposure to predators, foul weather, and other dangers. Like a well-built home, a suitable habitat must serve all of these purposes throughout the year.
The number of individuals of a given species that a habitat can support is called its "carrying capacity." This number fluctuates with the seasons, and a habitat generally supports more animals during the growing seasons than during the harsh days of winter. Carrying capacity will also change according to the age of the habitat's population. Finally, interrelationships between species influence carrying capacity for an area. The availability of prey species, for instance, affects the number of predators that can thrive.
Over the past 400 years, Virginia's wildlife habitats have changed in many ways. Where once grew large expanses of old growth forests covering hundreds of square miles, there grow today young forests interrupted by fields, roads, and houses. In lower reaches, large wetlands and flood plains along the rivers which serve as natural sponges have been filled to extend fields for the growing of corn and other crops. Large and small reservoirs cover areas where rivers and streams once flowed.
With the loss of habitat diversity and acreage comes a change in species mix and numbers. Gone are the woods buffalo, timber wolf, elk, and other large mammals. In their place is a white-tailed deer herd numbering almost a million individuals, more robins than in colonial times, fewer warblers, and more bass but less trout.
Throughout the Commonwealth wildlife is managed by balancing three considerations: the health of the species, the health of the ecosystem, and the needs of the people who share the space. The Virginia Department of Game and Inland Fisheries has the primary responsibility for managing all wildlife species. Wildlife is a public resource and, as such, the state must ensure that populations remain healthy to be enjoyed by future generations. This means that citizens must obtain a proper permit or license to possess any wildlife species. Because the majority of our wildlife live on private lands, public education and partnerships with individual land owners are extremely important to the overall health of all wild animals.
The relationship between man and animal is unique and as diverse as the number of species. Several factors influence which tools are used by individuals and the Department of Game & Inland Fisheries to manage wildlife. Although habitat management is a widely used tool for conserving wild animals, it is not always available. Most of the land in the Commonwealth is privately owned, and human uses sometimes come into direct conflict with habitat best management practices.
Since wild animals often cross state and international boundaries, Virginia wildlife and fisheries biologists work with their counterparts throughout North America to maintain healthy populations and habitats. Many migratory species-ducks, songbirds, anadromous fish, and bats, for example-depend upon good communication among biologists from other states or other countries to guarantee that habitat needs are met.
For management purposes, wildlife is legally divided into several categories. The largest of these is nongame. Included are most of the species found in Virginia. These species are important to the overall ecological health of natural systems but are usually taken for granted. Amphibians, insects, crayfish, birds, and reptiles are represented in this group. Most nongame species are not intensively managed. They thrive in the yards, forests, rivers, and meadows of the state.
Animals that are managed for recreation are collectively called game species. These are the species that can be hunted or fished with a proper license, allowing you to take a specific limit or number of individuals. Game species include trout, largemouth bass, deer, squirrel, turkey and a variety of other fish, birds, and mammals. The populations of game species are managed in such a way that our "use" is not detrimental to the species' survival.
Game species are managed by wildlife biologists and a network of game wardens, who enforce state regulations limiting the number of animals that can be taken. Some species, such as the fish bluegill, reproduce in large numbers and become stunted when living space is limited. Fishing removes a portion of these fish and provides recreation for thousands of citizens. For other species, such as deer, the only effective management tool is an annual hunting season. Since much of Virginia is covered by fields and forests, deer populations are increasing. Deer also do well in suburban settings where they feed on ornamental bushes (much to the gardener's dismay). Although there have been other attempts to control the increasing deer herd here and across the United States, hunting remains the most practical method.
The third category of wildlife covers those species that are listed as endangered, threatened, or of special concern by the federal or state government. These species are closely watched and intensively managed in order to stabilize their populations. The goal is to keep species off the list by effectively monitoring and managing all wildlife populations.
As of 1999, Virginia claims over 110 species on its list of Endangered and Threatened Wildlife. All of the species currently listed in Virginia have been placed on the list because of habitat loss. When a species' habitat is compromised and a suitable arrangement of food, water, shelter, and space is disturbed, the animal must adapt, move on, or die.
Unfortunately, in most situations the species cannot adapt or move on and many individuals die. When continued destruction of a habitat occurs over time, species become endangered or even extinct. Mussels are a case in point. Virginia has over 50 species of endangered or threatened mussels. The majority of these freshwater mussels are remnant populations native to the Tennessee and Ohio rivers. The lower stretches of those river systems have been dammed, changing habitat conditions and creating river bottoms unsuitable for mussel habitation. As a result, the mussels were confined to headwater reaches (which extend into Virginia). Many of these species are now extinct in Tennessee, Ohio, and West Virginia.
Other species can adapt if given protection over time. Bald eagles initially became endangered due to overuse of the pesticide, DDT. The pesticide caused a thinning in their egg shells and reproduction was disrupted.
The eagle also did not tolerate human activity near its nest, resulting in a limited number of successful nest sites. With the banning of DDT and its subsequent decline in the eagles' food chain, along with protection of their nest sites, bald eagles made a comeback. Their status was down-listed from endangered to threatened in 1995.
Today, human population growth and settlement patterns threaten their continued recovery. But promising signs are at hand. Younger eagles are building nests nearer to humans and seem to be less skittish about sharing their space. It appears they are adapting to man's presence.
|Year||Total Active Nests||Total Prod. Nests||Total Unprod. Nests||% Nests Prod.||Total Young Fledged||Fledglings per Prod. Nest||Fledglings per Active Nest|
How much time a population needs to adapt varies and is not readily understood. If a species fails to adapt and is not capable of moving on, it will become extinct. Unfortunately, we don't have answers to the adaptation question and, in some situations, adaptation is not an option. As you may know, in any ecosystem there is an interdependent relationship between plant and animal species. Although we may not currently understand all the links provided by and between ecosystems, we know that healthy plants and animals are critical and are mutually dependent, and they need clean air and clean water.
Humans also depend upon healthy, diverse ecosystems. Think for a moment about the tremendous jobs performed by some of the "lesser" species:
Each species has a "niche," or job, within an ecosystem and must work with others to keep the entire system healthy. Through research and continued observation, wildlife managers are learning how to balance basic animal needs with the needs of a growing human population in Virginia. While many decisions about wildlife remain, expanding our knowledge will help ensure that the decisions made are good ones.
Partners In Wildlife Conservation
Virginia families can help conserve wildlife by constructing and installing shelters for birds and mammals that require cavities for nesting or roosting. Department staff are available to consult with land owners on proper placement, to prevent over-predation of the nestlings. Improving public land by creating wildlife habitats on school grounds and state and federal properties, or privately in our own backyards, can greatly benefit species by providing much needed food, water, shelter, and travel corridors.