Edwin "Win" Everham, Ph.D.

Home range size and habitat use by the Eastern Indigo Snake (Drymarchon couperi) in South Florida: C- 44 Reservoir Site, Allapattah Flats, and Babcock Ranch

Third Annual Corkscrew Watershed Science Forum. January 27, 2017  Coral Springs, Florida

Content analysis of newspaper coverage of the Florida Panther (Puma concolor coryi) through time

Third Annual Corkscrew Watershed Science Forum. January 27, 2017  

Factors affecting the restoration of (Vallisneria americana) in the Caloosahatchee River

Charlotte Harbor Watershed Summit: Showcasing Our Accomplishments. March 28-30, 2017  Punta Gorda, Florida

Measuring the fate and non-target impacts of Dibrom using aerial ultra low volume (ULV) spray technology in mangrove wetlands

Florida Department of Agriculture and Consumer Services (FDACS)

2013
Co PIs: D.W. Ceilley, T. El-Hefnawy, and Jonathan Hornby.

Picayune Strand Restoration Project (PSRP)

Area Aquatic Fauna Monitoring Services

2018
Co-PIs: David W. Ceilley and Shawn Clem, in collaboration with Audubon Corkscrew Swamp Sanctuary and Johnson Engineering, Inc.

Ten Years of the Southwest Florida Frog Monitoring Network: Natural Variation and Human-driven Changes

Everham III, E.M., D.W. Ceilley, D.A. Croshaw, J. Firth, C.W. Gunnels IV, D.D. Hanson, S. Mariolan, R.J. Spear, B. Thomas, D.E. Van Norman, B.M. Whitmore, and J.R. Cassani

2013

The Southwest Florida Frog Monitoring Network was established in 2000 to collect long-term data on frog communities of the region. Routes of 10-12 stops were monitored monthly during the rainy season (June–September). Data on all frog calls during a three minute period were recorded using a three-level intensity code. We report results from the first ten years of monitoring to examine broad trends in the frog populations of southwest Florida. We explored the abundance of all frog species, as reflected by calling intensity, to elucidate potential factors that may influence long-term changes in frog populations and communities. These factors may include: natural variations of frog populations, disappearing and altered habitats through local and global human actions, landscape context, and the impacts of invasive species. At a regional scale, it appears that most frog species are maintaining natural variations in calling levels among years, suggesting that frogs are responding to annual variation and not regional or global changes. Use of behavioral indicators, such as calling intensity of frogs, may provide understanding of the environmental implications of altered hydroperiods and other landscape perturbations in our watershed and possibly some positive responses to restoration efforts.

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Terrestrial snake environmental DNA accumulation and degradation dynamics and its environmental application

Kucherenko, A., J. Herman, E. M. Everham III, and H. Urakawa

2018

There is an increasing need for effective biomonitoring tools that quantify patterns of habitat occupancy by reptile species. Environmental DNA (eDNA) has been regarded as an emerging tool to detect specific target species; however, the dynamics of accumulation and degradation of eDNA in terrestrial environments are poorly understood. This study determines the time required for terrestrial snakes to leave enough eDNA behind to become detectable (accumulation time) as well as its persistence (degradation time). By targeting mitochondrial cytochrome oxidase subunit I and 12S rRNA genes of Red Cornsnakes (Pantherophis guttatus) in a controlled laboratory setting, we found that eDNA can be detected 3.5 h after the snakes had contact with soil and for up to 6 d after their removal. Estimated accumulation rate of Pantherophis guttatus eDNA per gram of snake biomass per hour was 12.6 μg. We also evaluated the applicability of eDNA detection under field conditions by targeting the mitochondrial cytochrome b gene of a cryptic invasive species in South Florida, Burmese Pythons (Python bivittatus). Soil samples were derived from two groups of field sites: telemetry-monitored refugia (i.e., radiotelemetry evidence of python presence) and telemetry-absent refugia (i.e., no telemetry evidence, but monitored with a burrow camera at time of sample collection). We were able to detect the presence of python eDNA in 66.7% of the telemetry-monitored sites that fit within our laboratory-defined residence and degradation time window. Additionally, at the telemetry-absent sites, no eDNA from Burmese Pythons was detected and burrow cameras did not detect their presence. We concluded that eDNA technology using soil can be an effective detection tool for terrestrial snakes, particularly when used with other traditional tracking and sampling methods.

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