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Fishery Bulletin 102(1) 



South Florida Ecosystem Restoration Prediction and 

 Modeling Program, Program Management Committee, 

 were based on modifications of the benthic mollusc com- 

 munity (Turney and Perkins, 1972). In 1994 and 1995, we 

 used 60-cm bongo nets fitted with 0.333-mm mesh fished 

 from the port side of a 5.4-m boat. Beginning in 1996, we 

 used a paired 60-cm bow-mounted push net with 0.333- 

 mm mesh nets similar to that described by Hettler and 

 Chester (1990). 



Juvenile spotted seatrout were obtained from monitor- 

 ing programs established by the NOAA Center for Coastal 

 Fisheries and Habitat Research (NOAA) and Florida Ma- 

 rine Research Institute (FMRI). NOAA collections were 

 made from May 1995 through September 1997. Juveniles 

 were collected with an otter trawl towed between two 5-m 

 boats. The otter trawl measured 3.4 m (headrope) and was 

 fitted with a 3.2-mm mesh tailbag with 6-mm mesh. FMRI 

 collections were made in 1995 with a seine and a trawl. The 

 21.4-m center-bag drag seine was fitted with a 1.8 m x 1.8 m 

 x 1.8 m bag of 3.2-mm mesh. The 6.1-m (headrope) otter 

 trawl was fitted with a body of 38.1 -mm stretch mesh and a 

 3.2-mm mesh tailbag. The majority of juveniles (86 r i ) from 

 NOAA and FMRI collections were collected in 1995. 



Otolith microstructure analysis 



Otolith processing Otolith removal and preparation gen- 

 erally followed the methods of Secor et al. (1991). All oto- 



liths, except for the right sagitta, were mounted on a slide 

 with mounting media and archived. The right sagittal oto- 

 lith was embedded for transverse sectioning or polishing 

 (or both). The left sagitta was embedded for transverse sec- 

 tioning if the right was damaged. Sagittae were read with 

 a light microscope at lOOOx magnification under oil immer- 

 sion. The first increment was determined as that following 

 the core increment; which was defined as a well-defined 

 dark increment surrounding the core (Powell et al., 2000). 

 Two blind counts of increments were made by one reader 

 and if the counts differed by more than 5, then the otolith 

 was read again. If the counts were within the acceptable 

 range, the two counts were averaged. Based on a previous 

 validation study (Powell et al., 2000), 2.5 days were added 

 to the increment counts to obtain the daily age. A total 

 of 582 sagittal otoliths were aged. This total included 96 

 from larval collections from September 1994 through July 

 1997, 139 juveniles from NOAA collections from June 1995 

 through September 1997, and 347 from FMRI collections 

 from June 1995 through December 1995. 



Increment widths were measured on 347 otoliths from 

 FMRI collections (1995) by using image analysis. The 

 measuring path consisted of two segments: a ventral path 

 from the core to the 21 st increment and a ventral-medial 

 path along the sulcus, from the 21 st increment to the edge 

 (Fig. 2). The 21 st increment was selected as the transition 

 point in these measuring paths by test reading 30 otolith 

 sections representing the entire range of sample fish 



