Assessing Biogeography, Conditions, and Marine Protected Area Efficacy in the Dry Tortugas
Project Status: This project began in January 2005 and was completed in December 2012
In 2001, state and federal agencies established the Tortugas Ecological Reserve to protect extensive unspoiled shallow-water coral reefs that support a wide variety of marine life off the Florida Keys. The objectives of our project were to assess: the seafloor habitat and reef fishes of the reserve, the effectiveness of the reserve in protecting resources and providing economic benefits, and the stressors and conditions of the adjacent Dry Tortugas National Park.
Why We Care
The islands that compose the Dry Tortugas are one of America’s last wild ocean areas and are crown jewels of the Florida Keys National Marine Sanctuary. The Dry Tortugas contain seagrasses, coral reefs, and hard bottom, providing a haven for more than 400 species of reef fish, including tuna, grouper, and sharks.
What We Did
Our assessment provided a unique progress report of the reserve’s first five years under protected status. We measured the demographic changes in living-resource populations as well as the societal and socioeconomic benefits that had occurred since July 2001. The two main goals of our assessment were to determine:
if expected demographic changes, such as increases in the abundance, average size, and spawning potential of exploited marine populations, occurred in the Tortugas after the reserve was implemented and
whether short-term economic losses occurred to area fishers displaced by the reserve.
We also examined the condition of water resources in Dry Tortugas National Park in a separate effort (see link below to Assessment of Natural Resource Condition in and Adjacent to the Dry Tortugas National Park). The goals of that effort were to identify the state of knowledge of natural resources in Dry Tortugas National Park along with stressors and threats that affect them. Additionally, we describe current and future strategies to help park managers meet their objectives. A related report from the National Park Service is available that summarizes the science plan for the park and research natural area (see link below to Implementing the Dry Tortugas National Park Research Natural Area Science Plan).
We worked with more than two dozen scientists, researchers, and managers to complete this body of work. Partners included: National Marines Sanctuaries Program, Florida Keys National Marine Sanctuary, NOAA SPO Coastal and Ocean Resource Economics, NOAA/NMFS Southeast Fisheries Science Center, University of Miami - Rosenstiel School of Marine and Atmospheric Science, University of Massachusetts - Amherst Human Dimensions Research Unit and National Park Service South Florida-Caribbean Network, National Park Service Water Resources Division.
What We Found
Our significant outcomes and findings:
People employed in commercial fishing activities experienced no financial loss from the implementation of the reserve in the short-term. Additionally, reef fish catch from the Tortugas area increased pre- to post-implementation and continued on an upward trend. Finally, pre- and post-analysis of three important fisheries—shrimp, lobster, and king mackerel—again showed no losses to commercial fishermen as a result of the reserve.
Tortugas recreational fisheries likewise experienced no financial losses from the implementation of the reserve.
The Tortugas region likely experienced an early increase in the biomass of exploited species within a few years of the reserve’s implementation.
The Tortugas Ecological Reserve showed consistently higher coral cover when compared to the Dry Tortugas National Park and other unprotected sites. At the same time, a review of other studies showed an overall reduction in percent live coral cover in the reserve and other areas in the Tortugas region over a 15-year study period.
Fish metrics (i.e. abundance, biomass, and size) suggested that the reserve effectively protects some commercially valuable and exploited species, specifically mutton snapper and yellowtail snapper.
There was little evidence suggesting the reserve had a negative or positive economic impact on charter fishing and diving operations in the study area or that the reserve created an economic barrier to businesses.
Benefits of Our Work
Findings from An Integrated Biogeographic Assessment of Reef Fish Populations and Fisheries in Dry Tortugas: Effects of No-take Reserves (link available below) provided area managers and decision makers with additional information to support and guide ecosystem-based management decisions that will have a lasting impact on the living marine resources of the Dry Tortugas. This work helped inform a biogeographic assessment that took place in the Florida Keys Reef Tract, extending from Martin County south to the Dry Tortugas.
Regions of Study: Gulf of Mexico, Florida
Primary Contacts: Chris Jeffrey, John Christensen
Science for Coastal Ecosystem Management (Biogeographic Assessment, Marine Spatial Planning, Coral, Human Dimensions)
Related NCCOS Center: CCMA
- Jeffrey, C.F.G., V.R. Leeworthy, M.E. Monaco, G. Piniak, M. Fonseca (eds.). 2012. An Integrated Biogeographic Assessment of Reef Fish Populations and Fisheries in Dry Tortugas: Effects of No-take Reserves. NOAA Technical Memorandum NOS NCCOS 111. Prepared by the NCCOS Center for Coastal Monitoring and Assessment Biogeography Branch. Silver Spring, MD. 147 pp.
- Jeffrey, C.F.G., S.D. Hile, C. Addison, J.S. Ault, C. Currin, D. Field, N. Fogarty, J. Luo, V. McDonough, D. Morrison, G. Piniak, V. Ransibrahmanakul, S. G. Smith, S. Viehman. 2012. Assessment of Natural Resource Condition in and Adjacent to Dry Tortugas National Park. Natural Resource Report NPS/DRTO/NRR—2012/558. National Park Service, Fort Collins, Colorado.
- Implementing the Dry Tortugas National Park Research Natural Area Science Plan: The 5-Year Report. 2012. National Park Service and the Florida Fish and Wildlife Conservation Commission.
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