Within oak-hickory forest lived white-tailed deer, various rodent, eastern cottontail, and wild turkeys, who lived on the outer edges of the forest and took advantage of the cover to hide from natural predators such as the red fox and gray wolf. Gray squirrels and flying squirrels preferred the dense cover of the woods. Typically, the terrestrial animals and plants of the northwestern counties were similar to one another. Aquatic animals, however, differed widely depending on the region it found itself in. The Tennessee Valley region was divided by a narrow river, separating the area into lowlands and uplands. The lowlands had to have a higher net productivity due to greater access to moisture, which supported a greater diversity of species. The uplands did not support the same quantity of aquatic species, but still offered mass resources. The acorns and nuts produced from the forest attracted the same terrestrial and bird species seen in the lowlands.
Animal communities within the Little Mountain region were similar to those in the Tennessee River Valley, but did not have as many of animals. The low quantity could be attributed to the oak-hickory-pine forests, because pine forest tend to have lower quality soils. Mussels, fish, and water fowl differed between the two regions due to proximity of the Tennessee River. The Tennessee Valley region animal communities and plants were much larger and more diverse due to the closer proximity to the river. In the Little Mountain region, the fauna and flora were supported only by springs and streams. For instance, the streams and springs could only support a smaller range of mussel species that lived there.