Irrespective of its introduction, an abundant breeding population of nine-banded armadillos was established in the four adjoining counties of Brevard, Flagler, Putnam, and Volusia, and by 1949, the nine-banded armadillo expanded its range to 29 of Florida's 67 counties. In the 1960's, the nine-banded armadillo was introduced to Captiva and Sanibel islands (Layne 1984). Fitch et. al. (1952) reported the nine-banded armadillo occurs in Brevard, Flagler, Indian River, Orange, Osceola, Seminole, St. Johns, St. Lucie, and Volusia counties; in the adjacent parts of Lake, Martin, Okeechobee, Polk, and Putnam counties; and in small communities in Alachua, Broward, De Soto, Hamilton, Hardee, Hendry, Lee, Manatee, Marion, Nassau, Palm Beach, Pasco, and Sumter counties. The trend is a westward expansion into the panhandle by the Floridian population and an eastward expansion by the Texan population (Tiebout 1983). Humphrey (1974) concluded that the armadillo would have arrived in Florida on its own based on the characteristics of the animal and the existence of favorable habitat throughout the southeastern United States. He also believed that the armadillo would eventually spread to Florida from Texas as a result of its ability to survive and the disrupted habitats that humans created.
According to Neill (1952), the preferred habitats of the nine-banded armadillo are the drier areas of slash pine (Pinus caribaea) and wire-grass (Poa compressa) flatwoods, abandoned fields, rosemary (Andromeda spp.) scrub, and stands of turkey-oak (Quercus catesbaei)-longleaf pine (Pinus palustris), and gardens, cultivated fields, and orange (Citrus aurantium and Citrus sinensis) orchards. In general, the nine-banded armadillo is most successful in riparian habitats with rich leaf litter (Humphrey 1974). The nine-banded armadillo is an opportunistic species that flourishes in communities that are disrupted by the cutting of forests, grazing of cattle, and production of agricultural crops. The reduction of large carnivores, such as the red wolf (Canis rufus), coyote (Canis latrans), black bear (Ursus americanus), and others and concomitant reduction in predation also promote the spread of the nine-banded armadillo (Fitch et al. 1952).
The degree of competition by the nine-banded armadillo with native species and the extent of the nine-banded armadillo's altering of ecosystem in Florida are unknown. The animal's major food items are insects (78.5%) and miscellaneous invertebrates (19.1%) and includes amphibians and reptiles (1.0%); mammals, birds, and birds' eggs (0.5%); and vegetable matter (0.8%; Bushnell 1952; Nesbitt et al. 1977).
The most important economic benefits from the nine-banded armadillo is its predation on noxious arthropods such as the scarabid beetles that profoundly damage plants (Fitch et. al. 1952). Although it destroys scarabid beetles, the nine-banded armadillo also destroys insectivorous prey, spiders, scorpions, centipedes, small lizards, and amphibians (Fitch et al. 1952) and may therefore partly offset its consumption of beneficial insects. Armadillo burrows also serve as homes for fur bearers. Taber (1945) reported five opossums (Didelphis virginiana), five cottontails (Sylvilagus floridanus), four cotton rats (Sigmodon hispidus), one skunk (Mephitis mephitis), two burrowing owls (Athene cunicularia), and six nine-banded armadillos in a series of 50 burrows that were excavated in Chambers County, Texas. The harmful actions of nine-banded armadillos are the destruction of quail eggs, destruction of domestic poultry, damage by burrowing, damage to crops, competition with hogs, destruction of pine (Pinus spp.) seed, and interference with hunting and livestock handling (Fitch et al. 1952). Other positive impacts of the nine-banded armadillo include the destruction of many insects and other noxious pests, predation of venomous snakes, creation of shelter for other wildlife, cultivation and fertilization of soil, contribution of materials for the curio trade, and a source of human food (Fitch et al. 1952). As a result of their studies, Hall and Kelson (1959) concluded that the armadillo is a "natural and desireable part of the native fauna".
However, other biologists strongly contest that the nine-banded armadillo has harmful consequences for native communities because it is a major cause of leaf-litter and other ecological disturbances. The drying effect of turned-over leaf litter depletes the prey base for other insectivores and therefore reduces the food base for native amphibians and reptiles and for ground-dwelling birds (H.M. Tiebout, Professor, Department of Biology, West Chester University, Pennsylvania, personal communication).
Feral Hog or European Wild Boar (Sus scrofa). The domestic pig's current status is domestic, semidomestic, feral, introduced, and immigrant (Tiebout 1983). It has this status because the domestic pig and the European wild boar are classified as the same species and freely interbreed. Any attempt to differentiate wild and domestic stock is futile because of the continuous interbreeding. Hogs were originally introduced into Florida by Spanish explorers more than 400 years ago (Frankenberger and Belden 1976), and in 1912, a wild stock of hogs was introduced for hunters into the mountains of Tennessee and North Carolina (Jones 1959). This wild boar population probably expanded to Florida on its own while other hogs were simultaneously introduced repeatedly by Florida sportsmen (Tiebout 1983). The feral hog population continues to breed with escaped domestic stock, which widens their genetic diversity (Tiebout 1983). Most free-roaming hogs are classified as semi-domesticated because of what is known as "hog claims" or the entitlements of land owners to lay claim to all hogs on their lands (Tiebout 1983). When feral hogs exist in large numbers, they may harm agriculture, forestry, wildlife, and natural ecosystems (Tisdell 1982), primarily because of their habit of rooting while foraging. This behavior may disturb large patches of land (250 m2 or more). Rooting can destroy understory vegetation and habitat for ground-nesting birds, terrestrial salamander, and other animals and may cause soil erosion (Belden and Pelton 1975). More specifically, rooting disrupts vegetative communities and successional patterns and alters nutrient cycling. Therefore, feral hogs directly and indirectly hurt other wildlife with predation or with alteration of the forest-floor habitat (Tate 1984). Thompson (1977) hypothesized that the wild hog is a notable competitor for food with many wildlife species such as deer (Odocoileus virginianus), turkeys (Meleagris gallopavo), squirrels (Family sciuridae), and waterfowl (Anatidae). An inverse relation between higher predation by snakes where hog populations are low suggests that wild hogs may use snakes as a prey base and therefore reduce predation by snakes (Thompson 1977). Thompson also concluded that the European wild hog is a minor predator of bird eggs and nestlings. Indirect evidence exists that hogs may take injured wildlife such as deer (Odocoileus virginianus) and newly dropped fawns (Belden 1990). Wild hogs may also pose a serious threat to the traditional, coastal nesting areas for marine turtles, especially the loggerhead turtle (Caretta caretta; Thompson 1977). Feral hogs frequently are in the same areas as domestic sheep and cattle and thus elevate the possibility of transmission of any disease to livestock. Because humans altered the populations of predators on the feral hog, wild hog populations may increase to damaging levels without human intervention (Tisdell 1982). Feral hogs can serve as vectors of diseases and parasites to domestic pigs (Becker et al. 1978; McVicar et al. 1981; Forrester et al. 1982; and Greiner et al. 1982). The hogs are able to smell dead animals, which may carry diseases and parasites and become infected while feeding on the carcasses and subsequently spread diseases and parasites to other species, including domesticated hogs.
Wild hogs are officially regarded as pests, and their eradication is a desirable, if as yet unattainable, goal (Tisdell 1982). However, if feral hogs were eradicated, the landowners but not the hunters would be accommodated (Tisdell 1982). The only minimal benefit from feral hogs is their consumption of the larvae of leaf-eating beetles, and their rooting may promote the regeneration of cypress pines (Taxodium spp.; Tisdell 1982).
Although the feral hog does not benefit the environment, it has economic significance (Belden 1990). Because hogs are hunted widely, they are an important source of income and an important source of food. However, cost-benefit analyses are subjective because costs and benefits depend on the current market and on the opinions of the evaluators (Tisdell 1982). "In order to reduce the population of wild hogs, two types of policy measures have been adopted: (a) the declaration of the wild hog as a noxious animal, and (b) the payment of bonuses or royalties on hog snouts" (Tisdell 1982:381). These actions may, however, promote the peoples' preservation of this species for monetary gains.
The feral hog also harms agriculture (Tisdell 1982). It competes with cattle and sheep for grass; damages fences, dams, watering points, and roads; and promotes erosion by its wallowing and digging habits.
Although feral hogs also cause many economic problems, people continue to replenish stocks of hogs because they are a principal game species (Belden 1990). They are in areas such as the Everglades (Everglades Recreational Planning Board 1974) and the Big Cypress Swamp. During a 1980-81 survey, an estimated nearly 21,000 hogs were killed (Belden 1990). The Florida Game and Fresh Water Fish Commission considers wild hogs a valuable natural resource that can supply many days of recreational hunting, although the agency has problems with maintaining populations without restocking (Belden 1990). In the 1960's and 1970's, more than 4,500 hogs were relocated at approximately $39-$86/hog at 1990 prices (Belden and Frankenberger 1977). Another problem has been the miscalculation of restocking that created an overabundance of wild hogs (Belden 1990).
