SGER-Assessing the Impact of a Macro-algal Outbreak in Tampa Bay, Florida

University Of South Florida, Tampa FL

Investigators

Abstract

Sites within Tampa Bay Florida have recently been found to have an outbreak of a rhizophytic green alga, Caulerpa prolifera. Historically this alga has been present in the Bay, but has never been known to be persistent and extensive in its cover. While C. prolifera is not invasive per se in Tampa Bay, its rapid increase in cover and overgrowth of seagrass triggers concern that we may be witnessing a major habitat shift in shallow water communities in this region as has occurred in other regions of the world. The spread of C. prolifera in Tampa Bay has implications for both the biological and physical attributes of the seagrass ecosystem. Fortuitously Drs. Thomas and Bell have a long-term data base on the area that can be used as a baseline to investigate the algal outbreak. They will take advantage of the opportunity to document the beginning stages of what appears to be an algal displacement of the dominant vegetation in the area. They will 1) document the extent of C. prolifera spread in 4 sites where historical data are available, and 2) assess possible community implications of a habitat shift by comparing invertebrate and epiphyte abundance, hydrodynamic regime, and nutrient exchange between the benthos and the water column in seagrass versus C. prolifera ?dominated landscapes. With support from the SGER award and building upon their combined backgrounds in seagrass landscape ecology and hydrodynamics, Drs. Bell and Thomas will be able to document the beginning stages of the algal outbreak and gather unprecedented information on the temporal dynamics of habitat shifts in shallow waters or perhaps measure the resilience of seagrass ecosystems to a major perturbation. A graduate student will be supported on the project to help develop/conduct experimental protocols and assist in field studies. Likewise qualified undergraduates will be recruited to participate in the project. These investigators will incorporate findings into public web pages, highlighting the research on C. prolifera. I