508 



Abstract.— Fish assemblages of near- 

 shore hardbottom habitats of southeast 

 Florida were quantified at three sites 

 from April 1994 to June 1996. Random 

 2 X 15 m transects were visually censused 

 within two replicate areas at each site. 

 The hardbottom at one site was buried 

 by a dredge project to widen a beach 

 one year into the study. A total of 394 

 transects were sampled. Eighty-six 

 taxa (77 identified to species I from 36 

 families were censused. Grunts (Hae- 

 mulidae) were the most diverse family 

 (11 species), followed by the wrasses 

 (Labridae) and parrotfishes (Scaridae) 

 with seven and six species, respectively. 

 The most abundant species were sail- 

 ors choice i Haemulon parra I, silver porgy 

 iDiplodusargenteus). and cocoa damself- 

 ish iStegastes rariabilisi with mean 

 abundances (individuals/transect) of 

 4.5, 3.8, and 3.7, respectively. Early life 

 stages (newly settled, early juvenile, 

 and juvenile) represented over 80'7f of 

 the individuals at all sites. Newly 

 settled stages of over 20 species were 

 observed in association with hard- 

 bottom reef structure. Outside of la- 

 goons, nearshore hardbottom areas are 

 the primary natural structures in shal- 

 low waters of mainland Florida's east 

 coast and were estimated to have nurs- 

 ery value for 34 species of fishes. After 

 one year, burial of approximately five 

 ha of hardbottom habitat at one site 

 lowered the numbers of individuals and 

 species by over 30x and lOx, respec- 

 tively. Due to their early ontogenetic 

 stage, many of these species may not 

 be adapted for high mobility in re- 

 sponse to habitat burial. Dredging ef- 

 fects may be amplified by burial prior 

 to and during spring and summer peri- 

 ods of peak lan.'al recruitment. 



Nearshore hardbottom fishes of 

 southeast Florida and effects of 

 habitat burial caused by dredging 



Kenyon C. Lindeman 



Division of Marine Biology and Fisheries, 



Rosenstiel School of Marine and Atmospheric Science, 



University of Miami 



4600 Rickenbacker Cswy, Miami, Florida 33149 



E-mail address (for K C Lindeman) klindeman:g'rsmas miami edu 



David B. Snyder 



Continental Shelf Associates, Inc. 

 759 Parkway St 

 Jupiter, Flonda 33477 



Manuscript accepted 28 August 1998. 

 Fish. Bull. 97:508-525 (1999). 



The southeast coast of mainland 

 Florida is within a biogeographic 

 transition zone of high marine 

 biodiversity (Briggs, 1974; Gilmore, 

 1995). This region is also undergo- 

 ing some of the most rapid human 

 population growth of any area of the 

 United States (Culliton et al, 1990). 

 Due to the economic and recre- 

 ational value of beaches, substan- 

 tial marine dredging projects (up to 

 1.5 X 10^ m'' of fill/project) are 

 commony used to widen beaches 

 that are subject to erosion in the 

 area (ACOE, 1996). Nearshore 

 hardbottom habitats are the pri- 

 mary natural reef structures of this 

 region at depths of 0-4 m and are 

 often buried or indirectly affected by 

 these projects. To date, no quanti- 

 tative studies of the fish fauna of 

 these habitats or the effects of beach 

 dredge-and-fill projects on near- 

 shore fishes are available (NRC, 

 1995). 



Nearshore hardbottom habitats 

 of this area are derived from accre- 

 tionary ridges of coquina mollusks, 

 sand, and shell marl which lithified 

 parallel to ancient shorelines dur- 

 ing Pleistocene interglacial periods 

 (Duane and Meisburger, 1969; 

 Hoffmeister, 1974). The habitat 

 complexity of these limestone struc- 

 tures has been expanded by colonies 



of tube-building polychaete worms 

 (Kirtley and Tanner, 1968) and 

 other invertebrate and macroalgal 

 species (Goldberg, 1973; Nelson, 

 1989; Nelson and Demetriades, 

 1992). In southeast Florida, most 

 nearshore hardbottom structures 

 are within 200 m of the shore. These 

 habitats are often centrally located 

 between mid shelf reefs to the east 

 and estuarine habitats within inlets 

 to the west. Therefore, they may 

 serve as settlement habitats for 

 immigrating larvae or as interme- 

 diate nursery habitats for juveniles 

 emigrating out of inlets (Vare, 1991; 

 Lindeman, 1997a). Nonetheless, 

 most administrative reviews have 

 concluded that the fish habitat 

 value of nearshore hardbottom and 

 the effects of dredge-based beach 

 restoration projects are minimal 

 (e.g. ACOE, 1996). 



This study quantifies nearshore 

 hardbottom fish assemblages on the 

 southeast coast of mainland Florida 

 over a 27-month period. The effects 

 of dredge-fill placement were also 

 examined because the hardbottom 

 habitat at one site was buried on 

 account of a beach restoration 

 project 12 months into the study. 

 Three primary objectives were ex- 

 amined. First, spatial and temporal 

 attributes of fish assemblages at 



