Current Projects
IFRE 4. Site mapping, site selection, and efficacy of marine reserves in the Gulf of Mexico and the South Atlantic as well as
studies of the coral restoration in the Experimental Oculina Research Reserve. NMFS NURP Wilmington. C. Koenig, G. Fitzhugh, C. Grimes, F.
Coleman. This project is intended to develop scientific siting criteria for establishing no-take marine reserves in the Gulf of Mexico. Potential sites are being mapped by side-scan sonar and laser-line scanning combined with in-situ observations (using ROV) and physical circulation modeling to identify sources and sinks of spawning products. Criteria are being established for the Gulf of Mexico Fishery Management Council that will ensure protection of essential fish habitat and important spawning aggregations of economically important reef fish species. The objective of the specific work on Oculina varicosa is to define habitat characteristics within the Experimental Oculina Research Reserve (EORR) off Ft. Pierce, Florida, and in the reference control areas outside of the reserve. Surveys are being conducted with laser line, ROV, drop video, and torpedo video to determine Oculina habitat condition. Extensive areas of Oculina habitat are known to be damaged or destroyed completely. Because recovery of fish populations depends on habitat condition, mapping is essential to characterizing health of spawning stocks. The results of this survey will be incorporated into our GIS database and will provide a basis with which to evaluate recovery of reef fish populations. This study also compares growth, survival, and
recruitment of transplanted Oculina colonies in destroyed and intact Oculina habitat. Our preliminary study verified the effectiveness of transplantation. Finally, the study monitores fish abundance and community structure over time at artificial transplant
modules, which are also designed as coral-head-simulating structures. They provide habitat complexity where none exists in the destroyed areas.
IFRE 5. Application of remote sensing/GIS to conservation of marine resources. NMFS Base funding. PI: Lyman Barger. This project applies new mapping technologies to surveys and projects including sea-grass surveys, marine mammal strandings, and a reef-fish distribution survey. All mapping from marine reserve siting studies and Oculina
Experimental Reserves is entered into the GIS database. An accurate spatial and time record allows an understanding of historical changes of these resources and the survey scale required for measurement of abundance or standing crop.
IFRE 6. Age and growth of reef fish. NMFS Base funding. G. Fitzhugh. Age structure is essential information for monitoring a population's status and recruitment history. This project develops age-length keys and age-length relationships for several reef species such as gag grouper; red grouper; red, gray, and yellowtail snapper; and red porgy. For gag grouper, comparison of recent data to a survey more than a decade old has allowed an analysis of the changes in age structure in conjunction with changes in fishing mortality.
IFRE 7. Reef fish reproduction. NMFS Base funding. A. Collins. Status of reef-fish stocks have been determined on the basis of the spawning potential ratio (SPR)--a ratio of the estimated reproductive potential of a fished to a nonfished stock. This project provides several of the necessary ingredients for an SPR for several species including maturity schedules, weight-dependent reproductive
relationships and fecundity estimates.
IFRE 8. The structure, function, and timing of jewfish (Epinephelus itajara) spawning in the eastern Gulf of Mexico. NMFS Endangered Species. C. Koenig, F. Coleman, A. Eklund.
The ultimate goal of this research is to define the behavior, demography and movement patterns of jewfish associated in spawning aggregations in the eastern Gulf of Mexico. Such information will lead to fishery-independent estimates of stock recovery and elucidation of the mating system of this important grouper species. Jewfish have been
overexploited to the point of economic extinction. As a result, Florida populations have been protected from exploitation since 1990, but the level of recovery in the EEZ is uncertain. Evaluation of the dynamics of spawning aggregations by visual and acoustic methods would provide a basis for monitoring recovery. That is, if jewfish abundance in spawning aggregations is a correlate of stock size, then these fishery-independent methods can be used efficiently to monitor recovery. The expected benefits from this proposed research will be the advancement of our scientific understanding of the reproductive processes of economically important marine fishes. This scientific information will improve management decisions through reliable jewfish stock-size estimates and by providing details of the jewfish mating system for comparison with that of other exploited groupers. In addition to fishing interests, commercial opportunities relative to diving ecotourism may arise. The impacts of this work will extend as far as jewfish are distributed, that is, the U.S. Gulf of Mexico, but especially south Florida, because population sizes are historically greatest there.
IFRE 9. Past and present trophic structure of Florida Bay
sea-grass communities and the relationship to associated coastal fisheries: diet and stable isotope analyses. NMFS, Coastal Oceans Program. J. P. Chanton (FSU Department of Oceanography), C. C. Koenig (FSU Department of Biological Science). The overall objective of this study is to investigate the changes in the dependence of the trophic web (including juvenile fishes and invertebrates) on various sources of primary production and to estimate the consequences of change, if it exists, on associated fisheries. The working hypothesis is that the Florida Bay trophic structure has shifted from a benthic system dependent on primary production by sea-grass epiphytic algae (or sea grass itself) to a pelagic system dependent upon planktonic algae production. The null
version of this hypothesis (i.e., no shift in trophic structure) will be tested. The specific questions addressed in this proposal are: (1) have the trophic relationships in Florida Bay changed as seagrasses have declined and plankton blooms have become more common? (2) has the character of the Florida Bay nursery appreciably changed? and (3) to
what degree are the surrounding coastal fisheries dependent on the Florida Bay nursery? Our work is designed to complement the studies of Thayer et al. (1996), who have reported changes in faunal communities based upon the results of quantitative sampling of fish and invertebrate species.
Shifts in the trophic structure can be detected with stable isotope analysis (13C, 15N, and 34S) of producer and consumer organisms. The sampling design incorporates a series of six sites within Florida Bay along an "impact gradient." Sea-grass beds along the northern side of the lower Keys (e.g. near the Content Keys) are used as a pristine comparison site. Sites will be selected in collaboration with FMRI and NOAA/NMFS collaborators and in consultation with other researchers (e.g. J. Fourqurean, J. Zieman, M. Durako). The sampling design was replicated in time (collections within two seasons, winter and summer). Historical samples are being analyzed according to a similar
temporal and spatial design as availability of specimens allows.
This work provides data necessary to validate the extensive modeling efforts integrating the biological and physical processes occurring in the Bay. This work is relevant to program goals in that it helps define the relationship between environmental change, habitat change, and the recruitment, growth, and survival of animals in Florida Bay. We address the direction of change in the Florida Bay ecosystem from a sea-grass-epiphyte-based system to a phytoplankton-based system, directing studies at the consequences to its function as a nursery for commercially and recreationally significant species. Our work addresses the effect of changing species composition on ecosystem processes and trophic pathways. The fundamental ecosystem shift that is apparently
occurring is a critical issue because it is directly relevant to the most significant regional management concerns of NOAA, the living resources of the bay.
IFRE 11. Distribution and abundance indexing of juvenile and
adult sharks in northeastern Gulf of Mexico coastal habitats. NMFS Highly Migratory Species. E. Cortés, J. K. Carlson, L. Trent. Delineation of nursery habitats and monitoring of stock abundance in coastal areas are important elements for shark stock assessment and management, but the distribution and seasonal abundance of juvenile and adult sharks in the shallow coastal areas of the Gulf of Mexico are poorly documented. The goal of this study is to increase our knowledge of the abundance and distribution of juvenile and adult sharks, location of pupping areas, growth rates of some key species, and recruitment of juveniles to estuarine or coastal areas. Specific objectives of this project are (1) to survey five coastal bay systems in northwest Florida to determine juvenile and adult shark abundance; (2) to determine habitat preference by sharks in these bay systems; (3) to continue monitoring of juvenile shark abundance indices at established stations in northwest Florida; and (4) to tag sharks for migration studies and obtain specimens for life-history investigations.
IFRE 12. Spawning-to-nursery connection for gag grouper: tests of mechanisms to explain sea-grass recruitment patterns. MARFIN/NMFS. 1997-1999. G. R. Fitzhugh, C. Koenig, F. Coleman, W. Sturges. The primary objective of this study is to identify the key mechanisms affecting year-class variability in gag grouper. Other objectives include testing three possible mechanisms explaining the 2- to 3-week variation in settlement time exhibited by juvenile gag in sea-grass beds along the west Florida coast, including (1) spatial and or seasonal differences in spawning, (2) habitat-related differences in survival upon settlement, and (3) seasonal differences in transport. Our goal of discriminating among mechanisms accounting for geographic differences in settlement patterns directly increases our understanding of the connection between spawning grounds and transport to nursery areas.
Our primary aim in this work is to differentiate among several factors that may influence spatial and temporal variation in recruitment of juvenile gag to sea-grass nursery grounds. This work relates directly to several other research areas our group has worked on for the last several years, including studies of reef-fish reproduction, reef-fish juvenile abundance, and eastern Gulf of Mexico oceanographic circulation patterns. Building on these previous projects we will add a comparative geographic study of spawning and settlement times for gag grouper, and we will complete a time-series data set that can be used in developing a fisheries-oriented oceanographic model of larval transport. It includes coupling annual variation in adult spawning distributions, juvenile abundance, and an otolith-based analysis of spawning and settlement times with physical data including wind, current-meter, and satellite-altimetry data. Our ultimate goal is to compare model transport predictions to otolith back-calculated times of spawning and settlement and cield-measured patterns of juvenile settlement and abundance across the west Florida shelf.
Past Projects
IFRE 1. Florida inshore bait shrimping: experimental analysis of bycatch exclusion efficiencies of roller-frame trawls and capture-related mortality of selected sea-grass-associated finfish species. Funded by MARFIN. F. Coleman, C. Koenig. Bycatch inarguably represents a significant waste of resources, but it is not clear to what extent this loss of biomass affects the health of specific populations or communities. Determining the actual ecological impact of trawl fishing on nontarget species requires knowledge of the underlying population densities of those species and their fate after capture. The overall goal of this project is to determine the individual and population level impacts of roller-frame trawlers on selected sea-grass-associated species of finfish that occur in the bycatch. The objectives are (1) to determine the population sizes of selected species caught during roller-frame trawl
operations; (2) to determine catch efficiencies of standard bait-shrimping roller-frame trawls under a variety of sea-grass composition and density conditions; (3) to field-test the exclusion estimates on commercial roller-frame boats during actual fishing
operations, again on the basis of absolute population densities; and (4) to determine capture-related mortality rates of selected species during field tests.
IFRE 2. Recruitment indices and sea-grass habitat relationships of the early juvenile stages of gag grouper, gray snapper, and other economically important reef fishes in the eastern Gulf of Mexico. FSU. Funded by MARFIN. F. Coleman, C. Koenig. This study involved a comprehensive investigation of the sea-grass habitat of the eastern Gulf of Mexico between St. Andrews Bay and Fort Myers, Florida, to determine its
potential as a nursery area for the production of economically important reef-fish species that have estuary-dependent juvenile stages in their life histories, particularly gag grouper and gray snapper. The objectives of this work were (1) to develop recruitment indices for gag grouper, gray snapper, and other sea-grass-recruiting juvenile reef fish in the eastern Gulf of Mexico; (2) to describe spatial and temporal utilization
patterns and ecological relationships of selected sea-grass-recruiting juvenile reef fish; and (3) to determine habitat suitability of various sea-grass habitats of the eastern Gulf of Mexico to selected juvenile reef-fish species. We accomplished these objectives by delineating and characterizing the habitat and community structure of major
shallow-water sea-grass community types in the study area; (2) by describing spatial and temporal changes in habitat characteristics and community structure, including utilization patterns of selected reef-fish species; (3) by determining the absolute abundance of selected economically important reef fishes relative to sea-grass community types; and (4) by describing movement patterns of selected reef-fish species within the estuarine environment and during egress from it.