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Geology topics

Kevin M. Enge

Publications and source records attributed to Kevin M. Enge.

6 recordsLinked to original sources

Persistence of a declining anuran species across its distribution

Information on a species’ population dynamics, such as changes in abundance and distribution, can be used to identify declining populations and initiate conservation efforts and protections. For the Ornate Chorus Frog ( Pseudacris ornata ), anecdotal observations of local extirpation and population declines have been noted, but trends in its range-wide population status are generally unknown. We used 2227 verified records of Ornate Chorus Frog presence from across the species’ distribution, grouped into 407 populations, and a modified Cormack-Jolly-Seber survival analysis to estimate the probability that historical Ornate Chorus Frog populations persist in the year 2024. Our results suggested that > 36% of historical Ornate Chorus Frog populations are possibly extirpated (probability of persistence < 0.5) and that 33% of populations had a probability of persistence > 0.9. Many of these extant populations occurred in northwestern Florida, southeastern Alabama, and southern Georgia, USA. The probability of persistence was positively influenced by habitat suitability and mean winter precipitation and negatively influenced by urban imperviousness. Ornate Chorus Frogs in protected areas had a higher average probability of persistence compared to populations that were not in protected areas. Our study fills a knowledge gap by identifying regions where Ornate Chorus Frog populations are likely thriving and regions where they may be extinct.

Alabama, Florida, Georgia, Louisiana, Mississippi,

Coastal observations of alligator snapping turtles in the Florida Panhandle

The genus Macrochelys (alligator snapping turtles) inhabits river systems that empty into the Gulf of Mexico from Florida to Texas and contains the largest freshwater turtles in North America (Pritchard 2006). This paper details observations of Macrochelys on the coast and barrier islands in Franklin and Gulf counties, Florida, that contribute to our knowledge of their movements in brackish or saltwater ecosystems and occurrence on islands. Thomas et al. (2014) described turtles from this geographical area as a new species, Apalachicola alligator snapping turtle ( M. apalachicolae ), but Folt and Guyer (2015) disputed this designation, and many authorities still consider them to be alligator snapping turtles ( M. temminckii ; e.g., Crother 2017, Turtle Taxonomy Working Group 2017).

Florida Field Naturalist

Habitat Suitability Index Models: Southern and gulf flounders

Both the southern and gulf flounders (paralichthrS lethostigma, f. albi~utta) are important commercial and recreationa species. Catch statlstics for flounder do not differentiate between species; however, southern flounders are more common than gulf flounders except on the gulf coast of Florida (Topp and Hoff 1972). The commercial fishery consists of incidental catches by shrimp trawlers. A total of 853,162 kg (1,880,900 lb) of unclassified flounder worth $572,142 was caught from the Gulf of Mexico in 1976 (U.S. Dep. Commerce 1980). The sport fishery consists of both hook-and-line fishing and gigging.

FWS/OBS