Abstract Detail

Molecular Ecology and Evolution

Kennedy, John Paul [1], Garavelli, Lysel [2], Truelove, Nathan K. [1], Devlin, Donna J. [3], Box, Stephen J. [1], Chérubin, Laurent M. [2], Feller, Ilka C. [4].

Ocean currents consistent with contrasting genetic patterns of West and East Florida red mangrove (Rhizophora mangle) range expansion.

Marine species expansion is influenced greatly by the strength and direction of prevailing ocean currents. In Florida, milder winters and a reduced frequency of freeze events have been linked to contemporary expansion of water-dispersed mangrove into areas previously dominated by temperate salt marsh. In this study, we evaluated the genetic effects and underlying mechanisms of red mangrove (Rhizophora mangle L.) expansion along both West (WFL) and East (EFL) Florida, using a combination of genetic analyses with multi-locus microsatellite data from eight populations and oceanographic model-based estimates of propagule transport. We found WFL conformed to theoretical expectations of range expansion, with pronounced genetic divergence at the range edge, whereas EFL deviated from expectations. These contrasting patterns are consistent with near-surface ocean currents that drive asymmetric propagule transport from WFL to EFL and translate into significant differences in diversity and differentiation between Florida range edges. Considering predictions of continued climate warming in the future, these findings suggest that the direction of ocean currents along the Florida peninsula may lead to a greater rate of further mangrove expansion in EFL compared to dispersal-limited WFL.

1 - Smithsonian Marine Station, 701 Seaway Drive, Fort Pierce, FL, 34949, USA
2 - Harbor Branch Oceanographic Institute, Florida Atlantic University, 5600 N US Highway 1, Fort Pierce, FL, 34946, USA
3 - Florida Atlantic University, Biological Sciences, 5600 N US Highway 1, Fort Pierce, FL, 34946
4 - Smithsonian Environmental Research Center, P.O. Box 28, 647 Contees Wharf Road, Edgewater, MD, 21037, USA

Keywords:
biophysical model
climate change
Genetic diversity
genetic discontinuity
mangrove
Microsatellite
ocean current transport
range edge.

Presentation Type: Oral Paper
Session: 40, Molecular Ecology and Evolution
Location: 102/Savannah International Trade and Convention Center
Date: Wednesday, August 3rd, 2016
Time: 9:15 AM
Number: 40006
Abstract ID:385
Candidate for Awards:Margaret Menzel Award