Josh Ennen, Ph.D
Aquatic Conservation Biologist
Josh Ennen, Ph.D
Aquatic Conservation Biologist
Tennessee Aquarium
Photo Credit: Todd Stailey
Photo Credit: Josh Ennen
Photo Credit: Josh Ennen
Photo Credit: Josh Ennen
Current Research
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Alligator Snapping Turtles
The Alligator Snapping Turtles (Macrochelys temminckii) is the largest freshwater turtle in North America, and the only turtle species in the world with a oral lure on its tongue used to attract fish prey. This species has experienced dramatic declines over the past 50 years due largely to overharvesting and habitat modification. In collaboration with Jon Davenport, I am currently investigating the distribution and abundance of this species in west Tennessee.
Morphology Variation and Reproductive Output
I have always been interested in the shell shape and size of turtles and have applied these traits to systematic studies but mostly in ecological ones. I am currently investigating the spatial patterns in sexual size dimorphism variation in turtles and trying to understand what abiotic factors drive the variation. Also, I am using shell shape and size measurements in a systematic study of Pseudemys species in collaboration with Jim Godwin. The most interesting of my projects related to morphology is the understanding the tradeoff between morphology and reproductive output in turtles.
Photo Credit: Todd Stailey
Headwater Stream Ecology
In collaboration with Jon Davenport and Kristen Cecala, I am investigating mechanisms driving vertebrate community composition in headwater stream of the Southern Appalachians. We use mesocosms and large artificial stream systems to conduct manipulative studies to investigate how salamander and fish communities will respond to temperature and flow variation. In particular, we are interested in how species-interactions might change (i.e., strength and direction) as a response to temperature warming and altered flow regimes.
Photo Credit: Josh Ennen
Renewable Energy and Wildlife
All energy production for human consumption has downside for wildlife, but as a conservation biologist, we need to figure out how to minimize these impacts; while maximizing energy production. I have been studying the renewable energy-wildlife conflict for almost a decade with my collaborator, Jeff Lovich.
Biogeography
Species are not randomly distributed across the landscape, and distribution are often related to some constraint that could be related to abiotic or biotic factors. In collaboration with several folks (i.e., Mickey Agha, Wilfredo Matamoros, and Chris Hoagstrom), I am interested in the "where" and "why" of turtle species and turtle communities (e.g., biogeographical provinces and ecoregions) at the continental and global scales.
Photo Credit: Josh Ennen
Photo Credit: Josh Ennen