Author Analytic: Powell, Allyn B., Donal E. Hoss, William F. Hettler Jr., David S. Peters, Lawrence F. Simoneaux and Stephanie Wagner.
Center: CCFHR
Team: Beaufort
Title Monographic: Abundance and distribution of ichthyoplankton in Florida Bay and adjacent waters.
Place of Publication: Homestead, Florida
Publisher Name: Everglades National Park, South Florida Research Center
Date of Publication: 1987
Report ID: Report SFRC-87/01
Extent of Work: 45 pp.
Location URL: http://www.ccfhr.noaa.gov/documents/reprint939.pdf
Notes: CCFHR reprint #939, Public Domain
Keywords: Resource and land use, CCFHR, Estuaries, Fisheries, Habitat, NOAA Fisheries
Type: Report
Abstract: An ichthyoplankton survey was carried on in Florida Bay and adjacent waters that focused on the abundance and distribution of larvae of four target species--red drum (Sciaenops ocellata), snook (Centropomus undecimalis), gray snapper (Lutjanus griseus) and spotted seatrout (Cynoscion nebulosus). Twenty sampling stations were established--eight to document larval entry into Florida Bay and adjacent estuarine waters, and 12 within Florida Bay and adjacent estuarine waters--to provide insight into larval fish distribution and movement.
Spotted seatrout was the only target species whose larvae were regularly collected. No snook, one red drum and 16 potential gray snapper were collected. Based on the distribution of early stage larvae, spotted seatrout spawned in intermediate to high salinity waters within western Florida Bay and adjacent estuarine waters, but did not appear to spawn in brackish waters. We never collected spotted seatrout in the Keys area. Temporally, spotted seatrout have a protracted spawning season with spawning minimal during late fall and winter and most intense from May to September.
Based on the absence of early larval stages, gray snapper, snook and red drum apparently spawn outside of the Park. All larvae identified as snapper larvae were found in the ocean but young juveniles were found both in Florida Bay and the ocean. It appears that gray snapper spawn near offshore reefs in the Atlantic Ocean and at least some enter the Park as juveniles. The lack of larval snook and red drum in our samples does not indicate they are absent from the area. Adults spawn outside the Park, thus the larval supply may be susceptible to considerable mortality prior to migrating into the Park. They are less vulnerable to the gear because they are relatively well developed, and they may not be available to standard ichthyoplankton gear due to preference for the poorly sampled microhabitats (e.g., crevices, the bottom and channel edges).
Step-oblique tows with standard ichthyoplankton gear was appropriate for sampling early stage trout larvae to determine the spatial and temporal distribution of spawning. The development of different gear may be required to study the late larval and early juvenile stage.
Although our research focused on the four target species we were able to gain an insight into the distribution and abundance of non-gamefish within Florida Bay and adjacent waters. One of the most striking patterns was the dominance by and ubiquitous distribution of gobiid larvae.
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