A Natural History of the Central Appalachians

Chapter 12: Birds and Mammals

CHAPTER 12 UNLIKE THE THREE GROUPS of vertebrates discussed in chapter 11 (reptiles, amphibians, and fish), birds and mammals are warm-blooded. Features that serve to distinguish birds from mammals are a skin covered by feathers (for both insulation and flight), forelimbs modified as wings (usually for flight, but not in the same manner as the wings of bats), and hollow bones (thus providing a lighter weight for flying). Moreover, vision and muscle coordination are highly developed in birds. Birds are the most motile of the vertebrates, and many species are characterized by a colorful plumage, which makes them easy to spot. As a result, birds are the best-known group of vertebrates. In contrast, except for a few of the larger or more active examples, mammals are much less conspicuous. Few birds are nocturnal, but there are many examples among the mammals. As a result, it is possible to live in the same place for years and not be aware of some the mammals that are present. This is particularly true for certain small mammals such as shrews and voles. BIRDS Because most birds are so highly motile, it is often difficult to assign a species to a particular habitat or even a particular region. Where a bird makes its nest is a major consideration, but this may not be the only habitat in which it occurs or even the one in which it is most likely to be observed. Nevertheless, birds are usually assigned to one of four categories on the basis of what has been called residency status. Permanent residents are those species found in a particular region throughout the year. Summer residents are species that are absent during the winter but present during the season when breeding occurs (spring or summer). Winter residents are species characteristic of more northern regions which come south to the Central Appalachians to spend the winter. Transients are species that simply pass through the Central Appalachians as they migrate north in the spring to reach the places where they breed and then south again in the BIRDS AND MAMMALS fall to reach the places where they spend the winter. It should be pointed out that not all birds fit neatly into one category or another. Nearly 300 species of birds have been recorded from West Virginia and more than 400 from Virginia, the two states that make up the greater portion of the Central Appalachians. The number of birds that breed within the region is much lower. Hall, in West Virginia Birds (1983), indicated that approximately 122 species had been reported to breed in the Appalachian Plateau of West Virginia, while the comparable figure for the portion of the Ridge and Valley that falls within the state was 113 species. He also indicated that only 86 species were common to the assemblages of species for the two areas. If the total area under consideration were extended to encompass the remainder of the Ridge and Valley (in Virginia and a small area of Maryland) along with the Blue Ridge, this number would certainly increase, so it would be safe to assume that at least 150 species of birds are truly characteristic of the Central Appalachians. The wild turkey is the largest bird found in the region: adult males can weigh more than twenty pounds (fig. 106). Females are somewhat smaller. The wild turkey exhibits an example of what is known as sexual dimorphism, the term used to describe the condition in which males and females of the same species differ in color, form, or both. The male wild turkey (called a tom or gobbler) has a dark, iridescent brown body, a featherless blue and pink head, and wattles on the throat and neck. Females (called hens), in addition to being smaller, have feathers that are shades of brown and gray. Benjamin Franklin wanted the turkey to be our national bird, but when a vote was taken, the bald eagle won by a single vote. The wild turkey is a permanent resident in the Central Appalachians. It scratches on the ground for seeds and nuts but will also eat insects. Today the turkey is common, but this was not always the case. During the early twentieth FIGURE 106 Wild turkey, the largest bird found in the Central Appalachians 199 12 BIRDS AND MAMMALS predators from their nests and young...