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Steve Johnson - University of Florida. Gainesville, FL, US

Steve Johnson

Professor | University of Florida

Gainesville, FL, UNITED STATES

Steve Johnson is an expert in natural history and amphibian and reptile conservation. Steve has worked extensively with imperiled species.


Steve Johnson is a professor in the Department of Wildlife Ecology and Conservation in the College of Agriculture and Life Sciences. Prior to his position at UF, Steve worked as the State Sea Turtle Program Coordinator in North Carolina and as a research wildlife biologist with the US Geological Survey. At the USGS, he coordinated efforts for the national Amphibian Research and Monitoring Initiative (ARMI) in the southeastern United States.

Areas of Expertise (12)


Cane Toads

Cuban Treefrogs



Invasive Species





Tegu Lizards


Media Appearances (1)

'Frogmaggedon' in Florida town after Hurricane Ian

Fox Weather  online


Hundreds of thousands of frogs have descended upon a Florida neighborhood in Edgewater. Some are calling it a "frog-mageddon," and it's leaving residents wondering where in the world these amphibians have come from.

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Articles (4)

Effects of semi-constant temperature on embryonic and hatchling phenotypes of six-tubercled Amazon River turtles, Podocnemis sextuberculata

Journal of Thermal Biology

Cassia S.Camillo, et. al


We evaluated how constant incubation temperatures affect life-history traits pre-hatching and post-hatching of the six-tubercled Amazon River turtle, Podocnemis sextuberculata. Six-tubercled Amazon River turtles showed the highest pivotal temperature reported for any turtle. The relatively narrow TRT may limit the evolutionary potential of this vulnerable turtle in the face of global warming. Future incubation experiments at a finer scale (33°C–36 °C) are warranted to refine the sex-ratio reaction norm.

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Rat Lungworm (Angiostrongylus cantonensis) in the Invasive Cuban Treefrog (Osteopilus septentrionalis) in Central Florida, USA

Journal of Wildlife Diseases

Ellis C. Chase, et. al


Cuban treefrogs, Osteopilus septentrionalis, were grossly examined for parasites and parasite species confirmed by PCR. Angiostrongylus cantonensis larvae were recovered from the hind leg muscle of O. septentrionalis. This is the first report of the zoonotic rat lungworm in the Cuban treefrog and new geographic location in Florida. Angiostrongylus cantonensis, the rat lungworm, is a zoonotic nematode parasite that relies on various rat species, mainly Rattus spp., and gastropods to complete its life cycle.

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Population Size and Structure of the Ornate Diamondback Terrapin (Malaclemys terrapin macrospilota) on Small Gulf Coast Islands in Florida

Chelonian Conservation and Biology: Celebrating 25 Years as the World's Turtle and Tortoise Journal

Eric Suarez, et. al


Management decisions for species are often based on estimates of abundance, which can be difficult to obtain for species that are a challenge to survey, as are some reptiles. Information on abundance and population status are lacking for the diamondback terrapin (Malaclemys terrapin), a coastal species that inhabits brackish waters and plays an important trophic role in the saltmarsh ecosystem. Population declines are suspected throughout the species' range, and its population status is unknown in Florida.

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Diet of the invasive Argentine Black and White Tegu in central Florida

Southeastern Naturalist

Todd S. Campbell & Steve A. Johnson


Salvator merianae (Argentine Black and White Tegu, hereafter also ABWT) is a large bodied, omnivorous lizard native to South America. In Florida, where the species was introduced via the pet trade and is invasive, there are at least three established populations as well as numerous one-off observations. We collected ABWTs from public and private property to determine their diet in central Florida (Hillsborough County) from 2012 to 2016.

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