9.1.6.2.4. Responses of fish and shellfish to habitat changes 
The purpose of this program is to quantify and compare densities of fishes and decapods in 
central Florida Bay basins (subject to hypersalinity) and western Florida Bay (not subject to 
hypersalinity) as freshwater flow to central basins is increased. This work is being done in 
cooperation with the National Biological Survey.^ 
9.1.6.2.5. Marine mammals 
Aerial surveys beginning in the late 1970s indicated that Florida bay and the Florida Keys are 
habitat for bottlenose dolphins. This species accumulates toxins and pollutants and can be used 
as an indicator of ecosystem health. To provide census information, movements, and habitat 
use, field observer surveys will be supplemented with satellite and/or radio/sonic tags. To 
obtain information on animal condition and health, individuals will be captured alive and tissue 
samples obtained for chemical analyses. Repeated captures of the same individuals over time 
will be necessary to establish an adequate time series.* * 
9.1.6. 2 . 6 . Seagrass habitat health 
The NMFS Beaufort and Galveston Laboratories are conducting fishery habitat sampling along 
salinity gradients in northwestern Florida Bay. To date, three sampling trips have been 
conducted to evaluate fisheries populations in low salinities (9-17 %o) and salinity transition 
(>20 °/oo) areas in the vicinity of Little Madeira and Madeira bays. At each station, salinity, 
temperature, and bottom samples are taken for vegetation type and abundance. Fish and 
shellfish are identified from each collection and data will be compared with similar samples 
taken during 1990 - 1993 in the high salinity portion of the Bay for community structure 
comparisons. Additionally, Beaufort has established Global Positioning System (GPS) 
coordinates for these sites as well as for published sites sampled during the 1984 - 1985 pre- 
seagrass dieoff studies.* 
9.1.6.2.7. Pink Shrimp 
Pink shrimp are an indicator of the ecological health of Florida Bay. Pink shrimp support a 
valuable commercial fishery for which a relatively long time series of catch and effort is 
available. Statistical analysis of commercial catches suggests that pink shrimp are sensitive 
for freshwater inflow. Pink shrimp are a principal prey item of many game fish in the Bay. This 
study involves statistical analysis, biological modeling, physiological trials, caging 
experiments, resource analysis and genetic analysis. The study will characterize the within- 
year cohorts in the fishery and link them to specific nursery grounds in Florida Bay and nearby 
estuaries.^ This study is being done in cooperation with UM RSMAS and NBS. 
9. 1 . 6 . 2 . 8 . Pesticide analysis of agricultural nonpoint source waters 
There are significant agricultural activities in the upland areas adjacent to Florida Bay and 
these are potential sources of pesticides to the ecosystem. A baseline study to address 
potential inputs of agricultural pesticides was conducted in 1993 - 1994. As more freshwater 
runoff is diverted into Florida Bay as the result of the recent agreement on Everglades 
reflooding, there is an increased possibility of these pesticides entering the Bay. Research 
0 D. Hoss, NOAA/NMFS, 101 Pivers Isl. Rd., Beaufort. NC 28516. 919 728 8746. 
* L. Hansen, NOAA/NMFS, 75 Virginia Bch. Dr., Miami, FL 33149. 305 361 4264. 
* G. Thayer, NOAA/NMFS, 101 Pivers Island Road, Beaufort, NC 28516-9722. 919 728 8784. 
0 j. Browder, NOAA/NMFS, 75 Virginia Bch. Dr., Miami, FL 33149. 305 361 4270. 
67 
