Heather L. Cress^1*, Kimber L. Kingsland²,
Henry T. Smith^2,3, and Walter E. Meshaka, Jr.⁴

Abstract Forty-six species of exotic amphibians and reptiles are presently known to be established in Florida. Many of these species are successful inhabitants of buildings, including those located on public lands. Some of those exotic species are known to negatively affect native species as well as other exotic species. Ecological research on these species can provide useful information that answers the questions: why an exotic species succeeds or fails, how it affects or is affected by other species, and lastly how if at all the species can be controlled or eradicated? We highlight recent ecological studies conducted primarily on public lands by members of the “Parknership” research program concerning exotic amphibians and reptiles that inhabit buildings in Florida. We share those findings within the context of colonization dynamics and potential

and practical management techniques, which, in turn, could serve the management interests of public and private stewards alike that are interested in the control of exotic herpetofaunal building syntopes.

Introduction News that a thirteen-foot Burmese python (Python molarus bivittatus) ate a six-foot American alligator (Alligator mississippiensis) in Everglades National Park (ENP) garnered international attention—an extreme example of the consequences of invasion by exotic species in Florida. Displacement of indigenous species by exotic species alters the natural heritage of public lands, particularly within classes such as amphibians and reptiles, serving as both predator and prey in a biological community. Meshaka (2000:163) encapsulates the situation: “Because of continuing urbanization and influx of exotic species of amphibians and reptiles, extreme southern Florida is undergoing a profound human-mediated alteration of a major segment of the biological community that has yet to stabilize. The restructuring process of this community has resulted not only in the rapid accumulation of new exotic species, but also in species succession.”

Unlike the sensational invasion by the Burmese python, the ubiquitous presence of many exotic amphibians and reptiles throughout South Florida creates the public misperception that the mostly small-bodied animals are part of the natural Florida landscape. Such examples include primarily diurnally-active species, such as the anoles, and the generally nocturnally-active species, such as the Cuban treefrog (Osteopilus septentrionalis) and geckos. Among the nocturnal species, the Cuban treefrog negatively affects populations of two native treefrogs, the green treefrog (Hyla cinerea) and squirrel treefrog (Hyla squirella) (Meshaka 2001), and the exotic Indo-Pacific gecko (Hemidactylus garnotii) (Meshaka et al. 2004). Exotic geckos of the Genus Hemidactylus—  

having been placed in competition with one another for niche space due to human-mediated introductions—do not stably co-exist (Meshaka, 2000, 2001; Meshaka et al. 2004). Because these geckos are small in body size, mostly active at night and generally indiscernible in color and pattern, the progression of introduction, dispersal, and species replacement can and does very easily go unnoticed by most people. On public lands, the life history of the Cuban treefrog and its affects on other species was studied in Everglades National Park (ENP) (Meshaka 2001), and species replacement of the Indo-Pacific gecko by the wood slave (H. mabouia) was documented for both the Dry Tortugas National Park (Meshaka and Moody 1996) and ENP (Meshaka 2000, 2001).

The “Parknership” Research Program—a collaboration between Florida State Park biologists, other institutional and university research professionals, and college students conducting and publishing research on state protected areas—documents exotic amphibian and reptile colonization on public lands in South Florida. Program research strives to explain these colonization successes and failures providing useful information for managers making species management decisions concerning public lands, which are all too often susceptible to varying degrees of colonization by some segment of the 46 exotic amphibian and reptile species now known to be established in Florida (Meshaka et al. 2004; Meshaka 2006, 2007). Here, we discuss a series of projects performed by “Parknership” interns and affiliates involving buildingdwelling exotic amphibians and reptiles on two protected natural areas and a university campus in South Florida. Herein, we pay special attention to the exotic geckos and relate the findings to the larger issue of exotic species management applicable to private land holders and park-wide on public lands.  

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