Mangrove Studies

Southern Biscayne Bay's shoreline fish community been monitored visually twice a year since 1998 to compare fish use of mangrove prop root habitats along the mainland with that along the leeward side of the northernmost Florida Keys. This has been pursued by examining seasonal and spatial variation in fish taxonomic composition and diversity as well as variation in the frequency of occurrence, density and size structure of dominant fish taxa that occupy these mangrove?lined shorelines. The purpose of this MAP activity is to ensure the continuation and spatial expansion of this ~14-year baseline time-series with an emphasis on evaluating relationships between the shoreline fish community and variation in salinity/freshwater flow

To compare fish use of mangrove prop root habitats along the mainland with that along the leeward side of the northernmost Florida Keys.

Specific objectives of the mangrove-fish survey are: (1) to continue this ongoing, seasonally-resolved, multi-year monitoring effort that, to date, has focused on southern Biscayne Bay shorelines; (2) to expand this effort spatially to include shoreline sites in northern Biscayne Bay, Card Sound, Barnes Sound and northeastern Florida Bay; (3) to perform data analyses that evaluate inter-annual variability in these fish communities (and their component taxa) before, during and after CERP-related changes in freshwater flow are implemented; and (4) to correlate changes in freshwater flow with changes (if any) in the shoreline ichthyofauna, at both the species-specific and community level.

References

Bell, J.D., G.J.S. Craik, D.A. Pollard and B.C. Russell. 1985. Estimating length frequency distributions of large reef fish underwater. Coral Reefs 4:41-44.

Diaz, G.A (2001) Population dynamics and assessment of pink shrimp (Farfantepenaeus duorarum) in subtropical nursery grounds. Ph.D. Dissertation, University of Miami, Coral Gables Florida. 175 p.

Faunce, C.H, J.E. Serafy and L.J. Lorenz. Density-habitat relationships of mangrove creek fishes within the southeastern saline everglades (USA), with reference to managed freshwater releases. Wetlands Ecology and Management 12:377–394, 2004.

Humann, P. 1994. Reef fish identification: Florida, Caribbean, Bahamas. New World Press, Jacksonville, FL. 396 p.

Rooker, J.R. and G.D. Dennis. 1991. Diel, lunar and seasonal changes in a mangrove fish assemblage of southwestern Puerto Rico. Bulletin of Marine Science 49: 684 689.

Serafy, J.E., K.C. Lindeman, T.E. Hopkins and J.S. Ault 1997. Effects of freshwater canal discharge on fish assemblages in a subtropical bay: field and laboratory observations. Marine Ecology Progress Series 160: 161 172.

Serafy, J.E., C.H. Faunce and J.J. Lorenz. 2003. Mangrove shoreline fishes of Biscayne Bay, Florida. Bulletin of Marine Science.

Mangrove shoreline fish assemblages are characterized and quantified using a visual "belt transect" survey method (Rooker and Dennis 1991; Serafy et al. 2003). This entails snorkeling 30 m long transects parallel to the shore and recording the identity, number, and the size structure (minimum, mean and maximum total length) of fishes observed. Measured landward from the prop root edge, belt transect width is 2 m, thus area censused per transect is 60 m-2. Although a variety of sources are available to identify fish to species, identification of all individuals to the species level is not possible. Therefore, following Rooker and Dennis (1991), identification of problematic taxa is done to the genus or family level (e.g, Eucinostomus, Scaridae) and following Humann (1994), small, silvery, fork tailed fishes that tend inhabit the water column in large, mixed-species schools (e.g., Engraulidae, Atherinidae, and Clupeidae) is grouped. All visual surveys is conducted between 0900 and 1700 hours to minimize problems of low light and only by individuals with at least two years of experience identifying reef, estuarine and freshwater fishes underwater. Problems of potential observer bias in fish length estimation are addressed using a modified version of the training procedure described by Bell et al. 1985. The procedure involves the underwater presentation of a distribution of pre-measured lengths of PVC to all observers. Each observer is tested, informed of their bias and re-tested until their estimated length distribution does not differ significantly from the actual distribution (see Bell et al. 1985 for further details). A similar protocol is developed and implemented to maximize fish counting accuracy and precision. Measurements of water quality and depth are obtained for each fish census. With each visual survey, water temperature, salinity and dissolved oxygen is measured using a Hydrolab multi probe instrument or similar device. Depth is measured along (i.e., at 0, 15 and 30 m) each transect. Censuses have been conducted during consecutive wet and dry seasons (i.e., July to September and January to March, respectively) and will continue as such. Exact transect locations are chosen based on previous fish density and diversity information as well as measured and modeled salinity variation. Mainland census locations will depend on visibility at time of sampling will include the mangrove shorelines near the Oleta River (north Biscayne Bay), south of Matheson Hammock (south Biscayne Bay) and then extend southwest from Card and Barnes Sounds towards the central basin of Florida Bay. Visual assessments will not be conducted under conditions of poor visibility, danger due to large sharks or reptiles nor where access is limited by extremely shallow water depths. It is important to note that such conditions tend to increase west of Florida Bay's northeast basin -- census coverage is expected to decline in this direction. The anticipated number of censuses (i.e., stations) per shoreline per season is about 50 (i.e., 2 shorelines x 2 seasons x 50 stations = 200 censuses per year).

Open to everyone

Download data from provided links

Other data may be provided by request from the data steward

NOAA Data Quality Act Documentation and Pre-Dissemination guidelines

Data set is not for use in litigation. While efforts have been made to ensure that these data are accurate and reliable, NOAA cannot assume liability for any damages or misrepresentations caused by inaccuracies in these data, or as a result of these data being used on a particular system. NOAA makes no warranty, expressed or implied, nor does distribution constitute any such warranty

None

PC Files

Data were entered into spreadsheets and checked against the raw data sheet to avoid entry errors