Research Projects

Phylogeography of Florida mice (Podomys floridanus)

The Florida mouse truly epitomizes Florida terrestrial fauna. It is found only in peninsular Florida, is the only member of its genus, and has strong ecological associations with increasingly rare and ecologically important habitats. A xeric (dry) habitat obligate, the Florida mouse is commonly associated with gopher tortoise burrows, within which it commonly resides resides where populations persist.

Our research on Florida mice is focused around a comprehensive, range-wide assessment of genetic diversity and lineage structuring. We are addressing questions about range limits, centers of diversity and the evolutionary distinctiveness (and thus conservation "value") of peripheral populations. 

 

Demographics and behavior of Perdido Key beach mice (Peromyscus polionotus trissyllepsis)

The Perdido Key beach mouse is an endangered Peromyscus located on a small (~16 km long) barrier island in the Gulf of Mexico. This population has undergone extensive management interventions over the past 15 years, including multiple translocations, and ex situ breeding for conservation. and Our research has involved understanding the genetic impacts of these practices on the fragmented island population, and we are currently studying in depth, the annual demographic cycle of this rodent, its movement behavior, and mating system.

Evolutionary distinctiveness of isolated populations of Florida wildlife

Peripheral or marginal populations can display unique characteristics (genetic, morphological or otherwise) making them valuable for studying selection and the process of speciation. They are also valuable for understanding the process of range expansion and persistence in unique environments. We have been involved in the study of numerous fish and mammal species containing disjunct, peripheral or insular populations in Florida. Our common objectives here have been to evaluate the pattern and mechanisms of evolutionary distinctiveness of these populations and make science-based recommendations to management agencies looking to assess the conservation status of these populations. Recent and ongoing examples include:

  1. bluenose shiners and tesselated darters, both having highly fragmented ranges within Florida
  2. insular cotton rat population on Sanibel Island, currently recognized as a separate entity (from the perspective of listing)

Conservation status, demographic history, and mating systems of highly endemic species

"Highly endemic" is used to describe species that have extremely restricted geographic ranges. These are species that are often less affected by increasing habitat fragmentation, but rather are threatened by their rarity and limited distribution. We have studied a number of species under this definition, examples of which follow:

  1. Phylogeography of the okaloosa darter - This freshwater fish is restricted to a 450 square km region on the Florida Panhandle. Our work has shown that despite its small range, the fish is highly genetically structured largely due to marine incursion at the Chochtawhatchee Bay that largely isolates the the fish into 3 lineages structure west to east. 
  2. Florida bonneted bat - Florida bonneted bat (or Florida mastiff bat) occur in only a few counties in south Florida, making it one of the most restricted range bats in North America. We are studying the diversity, historic and contemporary population size, as well as gathering data on relatedness to better understand the mating system.
  3. Beach mouse genetic diversity and evolutionary distinctiveness. In addition to the Perdido Key beach mouse, we are also examining the status of Choctawhatchee, Santa Rosa populations, each of which have restricted, non-overlapping distributions along the Florida Gulf of Mexico coast.
  4. Florida bog frog - One of the rarest amphibians in North America, the bog frog is limited to a few seepage streams in Eglin AFB and surrounding environs. We have published on the conservation genetics of bog frogs and are continuing some unfunded research on their evolutionary history and significance.
  5. Panama City crayfish - We are beginning a genetic study in collaboration with the USFWS to examine the effect of habitat fragmentation on genetic patterns and demographic processes across the ~50 sq miles that include Panama City.