and Rare Habitats and Species
Healthy forests provide habitats for a wide array of plants and animals. In turn, forests consist of a wide variety of plants and animals. When forests are under extreme stress, individual species and their habitats become threatened, thereby endangering the health of the forest itself. These plants, animals, and forests are essential to maintain biological diversity in this region of the Mid-Atlantic Coast.
Examples of threatened species are those that require large blocks of forests to survive. They are not adapted to compete with species that evolved along forest edges and openings. These species are called forest interior dwelling species, or FIDS. Scarlet tanagers are FID birds that have higher success rates when raising young if they nest deep in the forest. Closer to forest edges, their eggs are often pushed out of nests by brown-headed cowbirds. Then the cowbirds lay their eggs in the nest, leaving the tanagers to raise the young cowbirds. Cowbirds are rarely found in the center of large forests.
The distance between blocks of forests influence the abundance of many FIDS. Some can survive in smaller forests if they are connected to other areas. Corridors, or narrow strips of forests connecting blocks, are often more beneficial if they are along waterways.
In the 350 years since European colonization, forests have been isolated, reduced in size, degraded, and destroyed. Subsequently, some species dependent upon these habitats are now rare, endangered, or no longer existing in Maryland.
In 1995, Maryland's Rare and Endangered Species List contained about 500 plant and 125 animal species. These species are protected by law under the Non-Game and Endangered Species Conservation Act of 1975. At least 185 of these species no longer exist in Maryland. Few people realize that elk once lived in every county of Maryland, as well as gray wolves, bison, and mountain lions. Six plants and 29 animals on Maryland's list were also on the Federal Endangered Species List.
Nearly one half of the species on the List are categorized as endangered. This is the highest category at risk of becoming extinct. Their continued existence as viable components of the State's flora or fauna is severely jeopardized.