Biodiversity of sessile and motile macrofauna on intertidal oyster reefs in Mosquito Lagoon, Florida.

ABSTRACT Our research focused on determining the diversity and abundance of sessile and motile macrofauna that use intertidal reefs of the eastern oyster Crassostrea virginica for feeding, settlement space or refuge in Mosquito Lagoon, Florida. Five replicate lift nets were deployed at six sites (three impacted reefs with seaward margins of disarticulated shells, three reference reefs without dead margins) to determine the species composition and numbers present on these reef types. All nets were deployed intertidally on backreef areas on living oyster reefs, just above mean low water. One and a half liters of live oysters and oyster shells were placed in each net (1[m.sup.2]) on deployment. Nets were surveyed for all fauna monthly for one year. Metrics used to evaluate habitat use were species richness (total number of different species found) and density (total number of organisms per net). Comparisons were also made between community assemblages found on the two different types of reefs in the area (with and without dead margins) and for sessile species, recruitment on living oysters versus disarticulated shells. Forty sessile and 64 motile species of macroorganisms were found utilizing the oyster reefs in Mosquito Lagoon. However, recruitment on live oysters was twice that on disarticulated shells. Significant temporal variations were documented. When the two reef types were compared, however, no differences were found.

KEY WORDS: oysters, Crassostrea virginica, habitat use, fishes, decapods, barnacles, invertebrates, lift nets

INTRODUCTION

Human activities threaten the productivity, diversity, and survival of coastal resources, leading to a growing need to understand and manage all coastal zones (e.g., Jackson et al. 2001). The Indian River Lagoon system (IRL) on the east central Florida coast is one such place. This estuary extends 251 km, from Ponce de Leon Inlet to Jupiter Inlet. The Lagoon system is a series of three distinct, but connected, estuaries: the Indian River, the Banana River and Mosquito Lagoon. This lagoon system may contain the richest biota of any estuary in North America (Provancha et al. 1992). It supports over 3,000 animal and plant species, 50 of which are listed as threatened or endangered. Commercially important intertidal reefs of the eastern oyster Crassostrea virginica are common in this estuarine system.

Diversity is extremely high in the IRL because of its location within a zoogeographic transition zone (e.g., Waiters et al. 2001, Smithsonian Institution 2006). Researchers have documented the substantial species diversity of many habitats and taxa in IRL waters: seagrass and its associated organisms (e.g., Virnstein et al. 1983, Dawes et al. 1995); finfish (Gilmore 1977, Gilmore 1995, Tremain & Adams 1995); elasmobranchs (Snelson & Williams 1981) and decapods (Smithsonian Institution 2006). To date, there have been no studies of the biodiversity on intertidal oyster reefs in the IRL.

Three-dimensional reef structures of Crassostrea virginica are created by years of successive settlement of larvae on adult shells (Dame 1996). Through its structural complexity, these ecosystem engineers create heterogeneity that is rare in marine systems dominated by soft-bottom habitats (e.g., Bartol et al. 1999, Micheli & Peterson 1999). Organisms use oyster reefs for many different reasons; mobile species may: (1) feed directly on live oysters, (2) use shell surfaces for spawning and (3) seek refuge from predation within oyster clusters (e.g., Tolley & Volety 2005), whereas sessile species use oyster reefs for attachment space.

Previous studies on intertidal oyster reef biodiversity include: Wells 1961 (North Carolina), Dame 1979 (South Carolina), Bahr and Lanier 1981 (south Atlantic coast), Crabtree and Dean 1982 (South Carolina), Wenner et al. 1996 (South Carolina), Coen et al. 1999a (South Carolina), Posey et al. 1999 (North Carolina), O'Beirn et al. 2004 (Virginia) and Tolley et al. 2005 (Florida, Gulf of Mexico). In most of these studies, the primary focus was on motile species (fish and crustaceans). Our study adds to this database by investigating the recruitment of motile macrofauna on backreef regions of intertidal oyster reefs of Crassostrea virginica in the IRL system along the Atlantic Coast of Florida. In addition, this is the first study in Florida to quantify diversity and abundance of all sessile macrofauna on oyster reefs.

METHODS

Study Site

All research was conducted in Mosquito Lagoon, within the boundaries of Canaveral National Seashore (28[degrees]90.68W; 80[degrees]82.06N) (Fig. 1). Except where dredged, the average depth of the Lagoon is less than 1 m and the current is primarily wind-driven (Waiters et al. 2001). Annual salinity ranges between 18 and 45 ppt, depending on rainfall (Grizzle 1990, Waiters et al. 2001).

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Within a 5-y period (1998-2003), the number of recreational boat registrations within the counties that border Mosquito Lagoon increased by 43% (Wall et al. 2005). This increasing intensity of year-round boating has helped create piles of disarticulated shells (dead margins) on the seaward edges of oyster reefs along major navigational channels in these shallow waters (Grizzle et al. 2002, Wall et al. 2005). We compared back-reef areas on reefs with and without dead margins to determine if recreational boating pressures influenced biodiversity.

Lift Net Field Sampling

Six oyster reefs were selected for this study, three impacted reefs (with dead margins) and three reference reefs (without dead margins). All were within a 5-km radius (Fig. 1). Five replicate lift nets were placed on the back-reef area of each reef. The protected back-reef areas were chosen to minimize the loss of nets caused by water motion.

Lift net methods were adapted from Crabtree and Dean (1982), Coen et al. (1996a), and later modified by Tolley et al. (2005) for use in Florida systems. We further modified the protocol to include the enumeration of sessile species recruiting to oyster reefs. Lift net frames were 1 [m.sup.2] and created from 3.8 cm diameter PVC. The nets were 0.5 m deep. The sides of the nets were made from 3.2 cm diameter opening mesh and the bottom was made from a 1-m square of 0.2-cm diameter opening mesh. The two mesh sizes were machine-sewed together using extra strength cloth thread. The sewn mesh was attached to the PVC frame with cable ties (tensile strength: 11 kg).

Lift nets were deployed intertidally, just above mean low water, on living oyster reefs. Volume normalized oysters and oyster shells in good condition (1.5 L) were placed in the lift nets. Half (0.75 L) were single, disarticulated shells from adults (Mean [+ or -] SE length: 77.5 [+ or -] 1.4 mm; weight: 21.5 [+ or -] 1.1 g) and half were similar-sized live clusters collected from the oyster reef. All were mechanically scraped clean of epiflora and epifauna. New shells and clusters were placed into the nets each month. Additionally, at the time of net retrieval, all nets were cleaned to remove organisms that had settled on the mesh or PVC frames.

Lift nets were retrieved by swiftly picking up the nets on two sides and collecting all recruited motile and sessile organisms. In the laboratory, we identified all organisms within 24 h and returned them alive to Mosquito Lagoon. Only sessile organisms attached to oyster shells within the lift nets were counted. Nets were collected monthly for 12 mo (June 2004 to July 2005). No data was collected for September 2004 because Hurricanes Charley, Jeanne and Frances required removal of nets and prevented data collection. Specimens of each species were preserved in 70% isopropanol to create a species archive for the University of Central Florida.

Environmental Variables

Permanent temperature monitors (Onset Stowaway Tidbit Temperature Loggers) were attached to cinder blocks and deployed at each site in water at the same depth as the lift nets. Temperature data were collected once each hour. Salinity was measured on net retrieval using a portable refractometer. Three sediment traps were deployed at each site at the same depth as the lift nets to determine sediment load accumulations during the 4-wk intervals between sampling. Each replicate, cylindrical PVC pipe sediment trap (10-cm diameter x 25 cm deep) was submerged flush with the substrate (Lenihan 1999). We capped traps underwater at the time of retrieval. The sediment traps were retrieved concurrently with the lift nets and new traps were immediately deployed to replace them. Total sediment mass was determined by drying samples at 60[degrees]C for 48 h in a drying oven (Econotherm Model Number 51,221,126) and weighing contents on a top-loading balance (O'Haus Scout 2-Model Number SC6010). Relative grain size was determined by grinding the dried sediment and sorting samples with a sieve (0.062 mm) to separate the silt/clay from the sand/gravel fractions.

Analyses

For all cases where analysis of variance (ANOVA) tests were run, prior to running the ANOVAs, homogeneity of variance and normality were tested using Levene and Kolmagorov-Smirnov tests. If significant differences were found with ANOVA, post-hoc Tukey-Kramer tests were run. Data assumptions of variance and normality were met for all ANOVAs at the P = 0.05 level, thus the data were not transformed.

Sessile Macrofauna

Response variables of species richness (total number of different species) and density (total number of individuals) were analyzed using a 4-way, nested. ANOVA. The factors in the nested ANOVAs were: (1) reef type (reefs with dead margins or reference reefs), (2) month, (3) site and (4) shell type (disarticulated shells or live oysters in clusters). Reef type, month and shell type were fixed factors, whereas site was random. Shell type was nested within site, and site was nested within reef type.

Motile Macrofauna

Community metrics of motile species were similarly examined with a 3-way ANOVA. Response variables of species richness and density were examined as in sessile species. For each ANOVA, the factors were reef type (fixed), site nested within reef type (random), and month (fixed).

Sediment Loads

A 3-way ANOVA was conducted to test whether sediment loads on oyster reefs varied as a function of the following fixed factors: reef type (reference or dead margins) and month. The third factor, site, was random and nested within reef type.

RESULTS

Biodiversity and Composition

Sessile Macrofauna

Twenty-five species of sessile invertebrates recruited to oysters and oyster shells in the lift nets during our study (Table 1). Barnacles in the genus Balanus (Arthropoda) dominated all samples numerically. Tube worms in the genus Hydroides, the jingle shell Anomia simplex, the eastern slipper shell Crepidula astrasolea, and the eastern oyster Crassostrea virginica were also very abundant (Table 1). Mollusca represented the most abundant phyla, with nine species found. Other phyla represented included Annelida, Cnidara, Porifera, Ectoprocta and Chordata (Table 1). Outside of the lift nets, 15 additional species of sessile organisms were found in small numbers on the intertidal oyster reefs and nearby subtidal areas throughout the course of our study in Mosquito Lagoon, although they do not represent any additional phyla (Table 2).

Measures of oyster community metrics with sessile invertebrates exhibited clear trends in Mosquito Lagoon. Species richness and the density differed temporally, because of the month of sampling (ANOVA: P < 0.001; Fig. 2, 3; Table 3, Table 4). Richness was significantly higher during June, July, August and October (P < 0.001; Fig. 2). Additionally, February had the lowest richness (Fig. 2). Density, the number of organisms per net, was significantly higher in June, July and August of 2004 than all other sampling periods (ANOVA; P < 0.001; Fig. 3). Furthermore, species richness and density were higher on living oysters in clusters than on single disarticulated oyster shells (ANOVA for both: P < 0.001; Tables 3, 4; Fig 4). Species found only on live oysters included mussel Lithophaga bisulcata, acsidian Perophera virdis and bryozoan Hippoprina verrilli. Reef type (reefs with dead margins or reference reefs) did not have a significant influence on the community metrics, species richness (P = 0.098) or density (P = 0.207) (Tables 3, 4). Site did not have a significant effect on species richness (ANOVA: P = 0.964) or density (P = 0.644) (Tables 3, 4).

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Motile Macrofauna

During this study, 64 motile species were found on oyster reefs in Mosquito Lagoon. Fifty-one species were collected using lift nets (Table 5) and an additional 13 species were observed by researchers elsewhere on reefs and in nearby subtidal waters (Table 2). Chordata was the most abundant phyla found to be utilizing the oyster reefs, with 23 fish species found. Mollusca were the second most prevalent phyla, with 20 different species found (Tables 2, 5). Other phyla that were represented in the collections included: Arthropoda (18 species), Echinodermata (2 species) and Annelida (1 species) (Tables 2, 5). The bigclaw snapping shrimp Alpheus heterochaelis and the flat mud crab Eurypanopeus depressus, dominated the collections numerically year-round (Table 5).

Species richness and density differed because of the month of sampling (ANOVA: both P < 0.001; Table 6, Table 7). Richness was higher in November December, January and May (Fig. 2). Density was significantly higher in June, November and December 2004 than any of the other sampling dates (Fig. 3). Reef type (reefs with dead margins or reference reefs) did not have a significant influence on species richness (ANOVA: P = 0.985) or density (P = 0.624) (Tables 6, 7). Site did not significantly affect species richness (ANOVA: P = 0.181), however it did significantly affect density (P = 0.002) (Tables 6, 7).

Environmental Variables

During the 13-mo study, the monthly mean temperatures in Mosquito Lagoon ranged from 16[degrees]C to 31[degrees]C (Fig. 5a). Salinity ranged from 25-35 ppt (Fig. 5b), falling within the typical average range of 25-45 ppt for the monthly mean in Mosquito Lagoon (Walters et al. 2001). The lowest salinity (25 ppt) occurred immediately after the 2004 hurricane season (Fig. 5b). Total sediment loads differed significantly between sites (ANOVA: P = 0.011), but not reef type (P = 0.234) (Table 8; Fig. 5c). After sediment loads were separated into fractions, percent silt/clay still did not differ significantly between reef type (ANOVA: P = 0.454) or sites (P = 0.482) (Table 9; Fig. 5d). During the months of June 2004 and June 2005, both sediment load and percent silt/clay differed temporally (ANOVA: P = 0.004 and <0.001, respectively). Tukey results showed sediment loads to peak in June 2004, whereas percent silt/clay fractions were highest in June and July 2004, and January 2005 (Fig. 5c, 5d).

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DISCUSSION

The assemblage of marcofauna associated with the intertidal oyster reefs during our lift net study was similar to those previously reported on oyster reefs in the southeastern United States (sessile species: Wells 1961; motile species: Meyer 1994, Breitburg 1999, Coen et al. 1999, Posey et al. 1999, Glancy et al. 2003, Tolley et al. 2005, Tolley & Volety 2005). Our data also support earlier research conducted in the Indian River Lagoon system that looked at the sessile species diversity on hard substrata, although not specifically associated with Crassostrea virginica (Mook 1976, 1980, 1981 and 1983). As is typical for shellfish assemblages (O'Beirn et al. 2004), the oyster reef community within Mosquito Lagoon was dominated (in terms of abundance) by only a few taxa (i.e., Annelida, Arthropoda and Chordata) (Table 1 and 5).

Sessile Macrofauna

The most abundant sessile species in the nets were in the genus Balanus. These organisms were present year-round on oyster reefs and numerically dominant in all nets. Balanus eberneus, the native ivory barnacle recruited to shells placed in lift nets during each month of our survey (Table 1). Monthly recruitment ranged from 87 recruits in February 2005 to 2,447 in July 2004. In fact, every net always had at least one B. eberneus. Balanus amphitrite, the purple striped barnacle, invaded the IRL approximately 100 y ago (J. Carlton pers. comm.). It was common but not as abundant as its conger (Table 1). Numbers of B. amphitrite decreased dramatically during the colder months of the year (Table 1). The abundance of these barnacles in this system outcompeting C. virginica for space may be associated with declines in oyster populations in Mosquito Lagoon (Boudreaux 2005). Dense sets of Balanus spp. monopolizing all free space on oyster reefs suggest intense spatial competition between oysters and barnacles in the IRL during summer and fall months (Boudreaux 2005).

The nonnative bivalve mussel, Mytella charruana, was found during this study (Boudreaux & Walters 2006). This South American bivalve was first found in lift nets in August 2004 and has since rapidly spread within northern Mosquito Lagoon (Boudreaux & Walters 2006). Although low numbers of this species may have predated our study, no individuals were recorded in a 3-y study in these waters between 1998 to 2001 (L. Waiters unpublished data). One individual of the invasive Asian green mussel Perna viridis, which has devastated some oyster reefs in Tampa Bay, Florida (Baker et al. 2003), was also recently found on a piling in Mosquito Lagoon (MB pers. obs.). It has not been found on Mosquito Lagoon oyster reefs to date. Both nonnative bivalves continue to be monitored within the IRL.

Motile Macrofauna

The two most abundant motile species sampled within the lift nets were the bigclaw snapping shrimp Alpheus heterochaelis (2,489 individuals) and the flat mud crab Eurypanopeus depressus (1,217 individuals) (Table 5). Previous studies found these two species to be present in temperate waters on both the Atlantic coast of North Carolina (132 individuals of E. depressus; Glancy et al. 2003) and the gulf coast of Florida (3,184 individuals of E. depressus, 364 individuals of A. heterochaelis; Meyer 1994). Similar to Tolley et al. (2005), we found the replacement of temperate species by tropical cogeners, including the replacement of the striped blenny Chasmodes bosquianus in the Northern Atlantic (Breitburg 1999, Coen et al. 1999) by the Florida blenny Chasmodes saburrae.

The fifth most abundant mobile species was the green porcelain crab, Petrolisthes armatus (Table 5). It is considered an invasive exotic along the South Atlantic Bight (Knott et al. 1999, Glancy et al. 2003). Populations of this species can historically be found in the Pacific (i.e., California to Peru) and the Atlantic (i.e., Africa, Ascension Island, Bermuda, Bahamas, Gulf of Mexico, West Indies, Caribbean and South America down to Brazil; Knott et al. 1999). Although the pathway of introduction remains unknown, ballast transport and increasing winter temperatures, which favor its establishment are possibilities (Knott et al. 1999). It was first collected along Florida's east coast in the 1930s in Biscayne Bay and Miami Beach (Knott et al. 1999). Slowly, it spread northward, becoming well established in the Indian River Lagoon system (Knott et al. 1999). Studies have shown abundances to increase dramatically in only a few years after introduction (Knott et al. 1999). The current range of P. armatus along the South Atlantic Bight stretches from South Carolina down to the southern tip of Florida (Knott et al. 1999).

Size and biomass data for several crustacean and fish species revealed that both juvenile and adult individuals were present on the reefs (Table 5). For example, large ranges were seen for the big-claw snapping shrimp Alpheus heterochaelis (length 1.6-2.5 cm; biomass 0.3-0.5 g), blue crab Callinectes sapidus (length 2.3-4.3 cm; biomass 1.5-6.6 g), stone crab Menippe mercenaria (length 1.0-2.1 cm; biomass 1.7-3.3 g), grass shrimp Palaemonetes vulgaris (length 2.5-3.8 cm, biomass 0.3-0.6 g) and pink shrimp Penaeus duorarum (length 2.8-6.5 cm, biomass 0.3-2.4 g) (Table 5). Within the Chordata family, different life stages were seen for the sheepshead Archosargus probatocephalus (length 4.4-9.7 cm, biomass 8.5-19.8 g), pinfish Lagodon rhomboides (length 2.3-7.7 cm, biomass 0.1-8.3), gray snapper Lutjanus griseus (length 3.0-11.2 cm, biomass 0.6-21.3 g), oyster toadfish Opsanus tau (length 2.3-9.0 cm; biomass 0.2-13.3 g), and numerous killifish and goby species (Table 5).

The blue crab Callinectes sapidus, the pink shrimp Penaeus duorarum and juvenile forms of several important finfish species were collected in the lift nets within Mosquito Lagoon (Table 5). Hence, commercially and recreationally valuable species are utilizing oyster reefs within Mosquito Lagoon, confirming the importance of oyster reefs to the economy of this region. These species were also found to be utilizing oyster reefs on the west coast of Florida (Tolley et al. 2005).

Additional comparisons can be made with the motile species found on oyster reefs in Mosquito Lagoon to lift net studies of intertidal reefs on the west coast of Florida (26[degrees] 25'56"N, 81[degrees] 48'34"W) (Tolley et al. 2005, Tolley & Volety 2005). Salinities and temperatures found in Mosquito Lagoon (mean: 33 ppt, 23.8[degrees]C) are comparable to the system studied in southwest Florida (mean: 32.5 ppt, 27.1[degrees]C). Overall species richness (the total number of species found per net) was found to be similar between the two different Florida locations (Gulf: 4-11 species/month versus Mosquito Lagoon: 4-11 species/month), whereas density was slightly lower in Mosquito Lagoon (Gulf: 20-400 organisms/net versus Mosquito Lagoon: 12-40 organisms/net). In both systems, there were more fishes than decapod crustacean species (Gulf: 16 versus 9, Mosquito Lagoon: 23 versus 18). In both locations, decapod crustaceans dominated all motile samples numerically.

Dead Margins Affect on Oyster Reef Communities

Dead margins, attributed to wakes from recreational boating in Mosquito Lagoon (Grizzle et al. 2002, Wall et al. 2005), did not have a significant effect on the back-reef usage of oysters as substrate by either sessile or motile species (Tables 3, 4, 6 and 7). The back-reef areas of both were also visually very similar. This suggests the back-reef areas on oyster reefs with dead margins function similarly to a reference oyster reef with no dead margin.

Although dead margins did not have an impact on richness or density of organisms found, sessile organisms preferred to settle on living oyster clumps rather than on the disarticulated shells placed within the nets (Fig. 4). The 3-dimensional structure of the two settlement substrates was very different. Disarticulated shells were single and loose, laid flat on the benthos, and were often covered by sediment. These shells were frequently displaced by water motion. Live oysters attached together to form clusters and rarely moved. These 3-dimensional clusters probably provided more protection and refuge from predators for sessile inhabitants than the 2-dimensional, disarticulated shells. Subsequent research has shown that reference reefs contained twice more oyster clumps than reefs with dead margins within Mosquito Lagoon (Stiner 2006). Combined, these results reveal a new negative impact of dead margins on sustaining biodiversity in Mosquito Lagoon.

Wall et al. (2005) found an increase in sediment accumulation on the seaward edges (fore-reef areas) of reefs with dead margins in Mosquito Lagoon and suggested this was caused by sediment resuspension associated with large numbers of boat wakes. Increased sediment has been shown to decrease the settlement of Crassostrea virginica (Boudreaux 2005). Thus, any difference in sediment loads between locations would have been predicted to have an effect on species assemblages between the two types of reefs (reference and dead margins). However, this study focused exclusively on the back-reef regions of oyster reefs and did not show any differences in sediment loads between reef types. Dead margins are hypothesized to protect these back-reef areas by preventing sediment accumulation.

During this study we documented the usage of intertidal oyster reefs in Mosquito Lagoon by 105 different species. This included 76 invertebrates and 29 chordates. The richness in diversity found within the reefs of Crassostrea virginica is comparable with other systems in the Indian River Lagoon system. A study of decapods associated with seagrass communities in the Indian River Lagoon showed remarkable diversity. In all, 38 decapod species were found in seagrass beds (Gore et al. 1981; Smithsonian Institution 2006) as compared with the 19 decapod species we found using oyster reefs (Tables 2 and 5). These examples demonstrate the extremely high diversity in the IRL that can be attributed to its important habitats, including seagrass beds and oyster reefs. The data from this study are an important step to gaining a better understanding of these oyster reefs and their essential role in the estuary. Additionally, this data provides a baseline from which to evaluate efforts to practice sustainable ecosystem management of Crassostrea virginica within Mosquito Lagoon.

ACKNOWLEDGMENTS

The authors thank the University of Central Florida and Canaveral National Seashore for their support in this project. Funding was provided by the University of Central Florida Biology Department, including Research Enhancement Grants (MB, JS), as well as the Aylesworth Foundation (JS), Sigma Xi Grant in Aid of Research (MB), and Florida Sea Grant (LW). We greatly appreciate all those who helped with data collection: M. Black, M.

Donnelly, N. Gillis, C. Glardon, J. Ledgard, A. McLellan, J. Sacks, P. Sacks, A. Simpson, E. Stiner, J. C. Stiner, and J. K. Stiner. We thank A. Benson, R. Gilmore, L. Haynes, C. Holden, H. Lee, and E. Reyier for help with species identification and A. Volety, G. Tolley and L. Coen for help with the methodology. Finally, we thank I. J. Stout, M. Luckenbach, L. Morris, R. Noss, P. Quintana, J. Fauth and an anonymous reviewer for greatly improving the text and analyses.

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Mook, D. H. 1980. Seasonal variation in species composition of recently settled fouling communities along an environmental gradient in the Indian River Lagoon, Florida. Estuar. Coast. Shelf Sci. 2:573-581.

Mook, D. H. 1981. Effects of disturbance and initial settlement on fouling community structure. Ecology 62:522-526.

Mook, D. H. 1983. Indian River Lagoon fouling organisms, a review. Florida Scientist 46:162-167.

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MICHELLE L. BOUDREAUX, (1) * JENNIFER L. STINER (2) AND LINDA J. WALTERS

Department of Biology, University of Central Florida, 4000 Central Florida Boulevard, Orlando, Florida 32816; (1) Everglades Partners Joint Venture, 701 San Marco Blvd. Suite 1201, Jacksonville, Florida 32207; (2) BCI Engineers & Scientists, 2000 E. Edgewood Drive Suite # 215, Lakeland, Florida 33803

* Corresponding author. E-mail: [e-mail]

TABLE 1.
Total numbers of sessile species collected in lift nets on intertidal
oyster reefs in Mosquito Lagoon, Florida.

                                 Common
Phylum       Species             Name               Total   6/04

Porifera     Hymeniacidon        Sun sponge            28      2
               heliophila
             Halichondria        Black volcano         66      1
               melandocia          sponge
             Cliona spp.         Boring sponge         13      0
Cnidaria     Aiptasia pallida    Sea anemone            2      0
             Haliplanella        Striped anemone        2      0
               luciae
Annelida     Hydroides spp.      Tube worms          2842    658
             Sabella spp.        Feather duster        46      2
                                   worm
Arthropoda   Balanus             Ivory barnacle      8782   2070
               eburneus
             Balanus             Purple striped      1524    438
               amphitrite          barnacle
Mollusca     Crassostrea         Eastern oyster       722    173
               virginica
                 recruits
             Anomia simplex      Jingle shell        1120    186
             Crepidula           Eastern slipper     1178    287
               astrasolea          shell
             Crepidula           Atlantic slipper      40     12
               fornicata           shell
             Diodora cayensis    Keyhole limpet         3      1
             Atrina rigida       Pen shell              1      0
             Tagelus divisus     Jacknife clam          1      0
             Brachidonetes       Scorched mussel        4      0
               exuctus
             Geukensia demissa   Ribbed mussel        128     21
             Mytella charruana   Charru mussel          3      0
             Lithophaga          Mahogany               1      0
               bisulcata           date mussel
Ectoprocta   Bugula neritina     Common               195      1
                                   bryozoan
             Hippoporina         Lacy bryozoan         40      0
               verrilli
             Zoobotryon          Spaghetti              2      0
               verticillatum       bryozoan
             Perophera viridis   Encrusting            16      0
                                   ascidian
Chordata     Styela plicata      Rough sea squirt      87      0

Phylum       Species             7/04    8/04   10/04   11/04

Porifera     Hymeniacidon            2      1       0      11
               heliophila
             Halichondria            0      0       0       0
               melandocia
             Cliona spp.             1      0       0       0
Cnidaria     Aiptasia pallida        0      0       0       0
             Haliplanella            0      0       0       0
               luciae
Annelida     Hydroides spp.        491    760     250     134
             Sabella spp.            1      9       6       4

Arthropoda   Balanus              2447   1380     720     430
               eburneus
             Balanus               461    450      46      16
               amphitrite
Mollusca     Crassostrea            92     54      69     104
               virginica
                 recruits
             Anomia simplex        178    184     151      93
             Crepidula             154    207     149      69
               astrasolea
             Crepidula               0      3       4       4
               fornicata
             Diodora cayensis        1      1       0       0
             Atrina rigida           0      0       0       0
             Tagelus divisus         0      0       0       0
             Brachidonetes           0      2       0       0
               exuctus
             Geukensia demissa      20     19       7       6
             Mytella charruana       0      0       3       0
             Lithophaga              0      0       0       0
               bisulcata
Ectoprocta   Bugula neritina         1      0       0       2

             Hippoporina             0      1      28      11
               verrilli
             Zoobotryon              0      0       0       0
               verticillatum
             Perophera viridis       2      0       1       5

Chordata     Styela plicata          0      0      26      17

Phylum       Species             12/04   1/05   2/05    3/05

Porifera     Hymeniacidon            0      3       0       1
               heliophila
             Halichondria            5      0       0       0
               melandocia
             Cliona spp.             0      9       1       2
Cnidaria     Aiptasia pallida        0      2       0       0
             Haliplanella            0      0       0       1
               luciae
Annelida     Hydroides spp.        111     66      33      65
             Sabella spp.            6      7       0       0

Arthropoda   Balanus               210    145      87     132
               eburneus
             Balanus                13      9       1       5
               amphitrite
Mollusca     Crassostrea            91      7       3      18
               virginica
                 recruits
             Anomia simplex         83     41       4      43
             Crepidula              59     31       4      25
               astrasolea
             Crepidula               0      9       0       1
               fornicata
             Diodora cayensis        0      0       0       0
             Atrina rigida           1      0       0       0
             Tagelus divisus         0      0       1       0
             Brachidonetes           1      0       1       0
               exuctus
             Geukensia demissa       4      7       0       2
             Mytella charruana       0      0       0       0
             Lithophaga              0      0       0       0
               bisulcata
Ectoprocta   Bugula neritina         0     16       0      18

             Hippoporina             0      0       0       0
               verrilli
             Zoobotryon              0      0       0       0
               verticillatum
             Perophera viridis       3      3       0       2

Chordata     Styela plicata          2      1       0       1

Phylum       Species             4/05    5/05   6/05

Porifera     Hymeniacidon            2      4       2
               heliophila
             Halichondria            0      3      57
               melandocia
             Cliona spp.             0      0       0
Cnidaria     Aiptasia pallida        0      0       0
             Haliplanella            1      0       0
               luciae
Annelida     Hydroides spp.         55     42     177
             Sabella spp.            1      9       1

Arthropoda   Balanus                99    251     811
               eburneus
             Balanus                 6      8      71
               amphitrite
Mollusca     Crassostrea             4     12      95
               virginica
                 recruits
             Anomia simplex         45     80      32
             Crepidula              44     73      76
               astrasolea
             Crepidula               1      0       6
               fornicata
             Diodora cayensis        0      0       0
             Atrina rigida           0      0       0
             Tagelus divisus         0      0       0
             Brachidonetes           0      0       0
               exuctus
             Geukensia demissa       4     19      18
             Mytella charruana       0      0       0
             Lithophaga              0      0       1
               bisulcata
Ectoprocta   Bugula neritina        82     48      27

             Hippoporina             0      0       0
               verrilli
             Zoobotryon              0      0       2
               verticillatum
             Perophera viridis       0      0       0

Chordata     Styela plicata         15      6      19

TABLE 2.
Additional macrofauna observed on oyster reefs within Mosquito
Lagoon. These species were not collected in the lift nets.

Sessile Species
Phylum            Species Name                Common Name

Annelida          Pal vdora websteri          Oyster mud worm
Mollusca          Modiolus americans          Tulip mussel
                  Mercenaria mercenaria       Hard shelled clam
                  Anadara transversa          Tranverse ark
                  Anadara ovalis              Blood ark
                  Martesia cuneiformis        Striated wood paddock
                  Crepidula convexa           Convex slipper shell
Ectoprocta        Conopeum spp.               Lacy crust bryozoan
                  Zoobotrvon verticillatum    Moss bryozoan
                  Hippoporina verrilli
Chordata          Mogula manhattensis         Sea grape
                  Botrylloides nigrum         Black tunicate
                  Botryllus planus            Royal tunicate
                  Botrylloides schlosseri     Goldenstar tunicate
                  Didemnum sp.

Motile species
Phylum            Species Name                Common Name

Arthropoda        Hexapanopeus angustifrons   Narrow mud crab
                  Limulus polyphemus          Horseshoe crab
                  Neopanope sayi              Say's mud crab
                  Pinnotheres ostreum         Oyster pea crab
Mollusca          Aplysia brasiliana          Sooty sea hare
                  Busycon contrarium          Lightening whelk
                  Busycon spiratum            Pear whelk
                  Fasciolaria hunteria        Banded tulip
                  Fasciolaria mlipa           True tulip
                  Melongena corona            Crown conch
                  Pleuroploca gigantean       Florida horse conch
                  Polinices duplicates        Atlantic moon snail
Chordata          Svmphurus plagiusa          Blackcheek tonguefish

TABLE 3.
Four-factor nested ANOVA comparing species richness of sessile
organisms in lift nets. Factors were reef type (dead margin or
reference; fixed), shell type (live clusters or disarticulated
shells) nested within site nested within reef type (random), and
month (fixed).

                                      Mean
Source                          df   Square      F     Significance

Reef type                        1    64.201   4.625      0.098
Site (Reef type)                 4    13.881   0.133      0.964
Shell type (Site (Reef type))    6   104.321  42.236     <0.001
Month                           11    85.401  34.576     <0.001
Residual                       697

TABLE 4.
Four-factor nested ANOVA comparing density of sessile organisms
in lift nets. Factors were reef type (dead margin or reference;
fixed), shell type (live clusters or disarticulated shells)
nested within site nested within reef type (random), and month
(fixed).

                                      Mean
Source                          df    Square      F     Significance

Reef type                        1  68406.006   2.265      0.207
Site (Reef type)                 4  30195.728   0.657      0.644
Shell type (Site (Reef type))    6  45976.603  16.335     <0.001
Month                           11  35020.837  12.443     <0.001
Residual                       697

TABLE 5.
Total numbers of motile species collected in lift nets on intertidal
oyster reefs in Mosquito Lagoon, Florida.

                                       Common
Phylum         Species                 Name                   Total

Echinodermata  Axiognathus             Brooding brittle star    1
                 squamatus
               Ophionereis             Reticulated brittle      3
                 reticulata              star
Annelida       Phyllodoce fragilis     Green oyster worn        3

Mollusca       Boonea impressa         Oyster mosquito          1
               Cerithiopsis            Awl miniature cerith    26
                 emersoni
               Cerithiopsis greeni     Green's miniature
                                         cerith                 1
               Cerithium atratum       Florida cerith           5

               Doriopsilla pharpa      Lemon drop sea slug     18

               Eupleura caudata        Thick-lipped drill       2

               Littorina irrorata      Marsh periwinkle         2

               Nassarius vibex         Mottled dog whelk       78

               Pyrgocythara            Plicate mangelia        48
                 plicosa
               Terebra salleana        Salle's auger snail      1
               Thais haemastoma        Florida rock snail       2
                 floridana
               Urosalpinx cinerea      Atlantic oyster drill   19

Arthropoda     Alpheus                 Bigclaw snapping       2489
                 heterochaelis         shrimp
               Callinectes sapidus     Blue crab               75

               Clibanarius vittatus    Striped hermit crab      2

               Eurypanopeus            Flat mud crab          1217
                 depressus
               Eurytium limosum        Broad-backed mud crab    4

               Heterocrypta granulate  Pentagon crab            1
               Libnia dubia            Doubtful spider crab     2

               Menippe                 Stone crab               3
                 mercenaria
               Palaemonetes            Grass shrimp            610
                 vulgaris
               Panopeus herbstii       Atlantic mud crab       534

               Penaeus duorarum        Pink shrimp             145

               Petrolisthes armatus    Green porcelain         584
                                       crab
               Rhithropanopeus         Harris's mud crab       243
                 harrisii
               Squilla empusa          Common mantis shrimp     1
Chordata       Archosargus             Sheepshead              21
                 probate-cephalus
               Bairdiella chrysoura    Silver perch             7

               Bathygobius soporator   Frillfin goby            1
               Chasmodes saburrae      Florida blenny           6

               Cyprinidon              Sheepshead minnow        3
                 variegatus
               Diapterus auratus       Irish pompano            1
               Floridichthys carpio    Goldspotted killifish    1
               Fundulus grandis        Gulf killifish           2

               Gobionellus             Darter goby             54
                 boleosoma
               Gobiosoma bosc          Naked goby             736

               Gobiosoma robustum      Code goby              267

               Haemulon                French grunt            34
                 flavolineatum
               Lagodon rhomboides      Pinfish                148

               Lucania parva           Rainwater killifish     84

               Lutjanus griseus        Gray snapper            25

               Mugil cephalus          Striped mullet           2

               Mugil curema            White mullet             1
               Opsanus tau             Oyster toadfish         40

               Paralichthys albigutta  Gulf flounder            1
               Paralichthys
                 lethostigma           Souther flounder         1
               Poecilia latipinna      Sailfin molly          109

               Sygnathus scovelli      Gulf pipefish           16

                                       Mean Length
Phylum         Species                 (cm)(range)

Echinodermata  Axiognathus             0.3
                 squamatus
               Ophionereis             0.2 [+ or -] 0.1
                 reticulata            (0.1-0.3)
Annelida       Phyllodoce fragilis     0.5 [+ or -] 0.1
                                       (0.4-0.6)
Mollusca       Boonea impressa         0.30
               Cerithiopsis            1.2 [+ or -] 0.1
                 emersoni              (1.0-1.6)
               Cerithiopsis greeni     0.4
               Cerithium atratum       2.2 {+ or -] 0.1
                                       (2.1-2.4)
               Doriopsilla pharpa      1.2 [+ or -] 0.3
                                       (0.7-2.0)
               Eupleura caudata        2.1 [+ or -] 0.4
                                       (1.7-2.5)
               Littorina irrorata      0.8 [+ or -] 0.1
                                       (0.8-0.9)
               Nassarius vibex         1.1 [+ or -] 0.1
                                       (1.0-1.3)
               Pyrgocythara            0.5 [+ or -] 0.1
                 plicosa               (0.5-0.8)
               Terebra salleana        0.4
               Thais haemastoma        0.8 [+ or -] 0.1
                 floridana             (0.7-0.8)
               Urosalpinx cinerea      1.5 [+ or -] 0.1
                                       (1.2-1.9)
Arthropoda     Alpheus                 2.0 [+ or -] 0.2
                 heterochaelis         (1.6-2.5)
               Callinectes sapidus     3.0 [+ or -] 0.3
                                       (2.3-4.3)
               Clibanarius vittatus    5.0 [+ or -] 0.1
                                       (4.0-5.0)
               Eurypanopeus            1.1 [+ or -] 0.1
                 depressus             (0.8-1.3)
               Eurytium limosum        1.0 [+ or -] 0.1
                                       (1.0-1.1)
               Heterocrypta granulate  1.5
               Libnia dubia            3.8 [+ or -] 0.2
                                       (3.5-4.0)
               Menippe                 1.6 [+ or -] 0.5
                 mercenaria            (1.0-2.1)
               Palaemonetes            2.9 [+ or -] 0.2
                 vulgaris              (2.5-3.8)
               Panopeus herbstii       1.8 [+ or -] 0.1
                                       (1.4-2.1)
               Penaeus duorarum        4.6 [+ or -] 0.5
                                       (2.8-6.5)
               Petrolisthes armatus    0.7 [+ or -] 0.1
                                       (0.6-0.8)
               Rhithropanopeus         0.9 [+ or -] 0.1
                 harrisii              (0.5-1.4)
               Squilla empusa          10.0
Chordata       Archosargus             7.2 [+ or -] 0.1
                 probate-cephalus      (4.4-9.7)
               Bairdiella chrysoura    4.6 [+ or -] 0.2
                                       (4.0-5.0)
               Bathygobius soporator   4.0
               Chasmodes saburrae      4.3 [+ or -] 0.2
                                       (4.0-4.8)
               Cyprinidon              5.5 [+ or -] 0.7
                 variegatus            (4.1-6.5)
               Diapterus auratus       7.3
               Floridichthys carpio    6.8
               Fundulus grandis        8.8 [+ or -] 1.7
                                       (7.1-10.5)
               Gobionellus             3.5 [+ or -] 0.3
                 boleosoma             (2.2-5.0)
               Gobiosoma bosc          3.1 [+ or -] 0.2
                                       (2.6-3.8)
               Gobiosoma robustum      2.9 [+ or -] 0.2
                                       (2.3-4.5)
               Haemulon                3.7 [+ or -] 0.3
                 flavolineatum         (2.1-5.5)
               Lagodon rhomboides      3.8 [+ or -] 1.0
                                       (2.3-7.7)
               Lucania parva           2.5 [+ or -] 0.3
                                       (2.0-3.3)
               Lutjanus griseus        5.9 [+ or -] 1.1
                                       (3.0-11.2)
               Mugil cephalus          22.0 [+ or -] 1.0
                                       (21.0-23.0)
               Mugil curema            11.5
               Opsanus tau             6.9 [+ or -] 1.2
                                       (2.3-9.0)
               Paralichthys albigutta  4.9
               Paralichthys
                 lethostigma           3.6
               Poecilia latipinna      4.8 [+ or -] 0.4
                                       (4.3-5.6)
               Sygnathus scovelli      6.6 [+ or -] 0.4
                                       (5.6-8.6)

                                       Mean Weight
Phylum         Species                 (g)(range)         6/04

Echinodermata  Axiognathus             0.1                  0
                 squamatus
               Ophionereis             0.1                  0
                 reticulata
Annelida       Phyllodoce fragilis     0.1                  0
Mollusca       Boonea impressa         0.1                  0
               Cerithiopsis            0.2 [+ or -] 0.1     3
                 emersoni              (0.1-0.6)
               Cerithiopsis greeni     0.1                  0
               Cerithium atratum       0.8 [+ or -] 0.1     0
                                       (0.7-1.0)
               Doriopsilla pharpa      0.1                  0
               Eupleura caudata        0.8 [+ or -] 0.5     0
                                       (0.3-1.3)
               Littorina irrorata      0.3 [+ or -] 0.1     0
                                       (0.2-0.3)
               Nassarius vibex         0.4 [+ or -] 0.1     2
                                       (0.3-0.5)
               Pyrgocythara            0.1 [+ or -] 0.01    4
                 plicosa               (0.1-0.2)
               Terebra salleana        0.1                  0
               Thais haemastoma        0.2 [+ or -] 0.1     0
                 floridana             (0.1-0.3)
               Urosalpinx cinerea      0.4 [+ or -] 0.2     1
                                       (0.2-0.9)
Arthropoda     Alpheus                 0.4 [+ or -] 0.1    54
                 heterochaelis         (0.3-0.5)
               Callinectes sapidus     3.4 [+ or -] 0.8     2
                                       (1.5-6.6)
               Clibanarius vittatus    2.5 [ 0.1            0
                                       (2.0-3.0)
               Eurypanopeus            0.6 [+ or -] 0.1   461
                 depressus             (0.5-0.8)
               Eurytium limosum        0.3 [+ or -] 0.1     0
                                       (0.2-0.4)
               Heterocrypta granulate  0.1                  0
               Libnia dubia            24.3 [+ or -] 0.3    0
                                       (23.5-25)
               Menippe                 2.5 [+ or -] 0.8     0
                 mercenaria            (1.7-3.3)
               Palaemonetes            0.4 [+ or -] 0.1     1
                 vulgaris              (0.3-0.6)
               Panopeus herbstii       3.3 [+ or -] 0.3    70
                                       (1.5-4.3)
               Penaeus duorarum        1.3 [+ or -] 0.3     0
                                       (0.3-2.4)
               Petrolisthes armatus    0.5 [+ or -] 0.1   383
                                       (0.3-0.6)
               Rhithropanopeus         0.6 [+ or -] 0.1     0
                 harrisii              (0.2-1.0)
               Squilla empusa          18.0                 0
Chordata       Archosargus             12.7 [+ or -] 1.9    3
                 probate-cephalus      (8.5-19.8)
               Bairdiella chrysoura    1.5 [+ or -] 0.2     3
                                       (1.0-2.0)
               Bathygobius soporator   0.8                  0
               Chasmodes saburrae      1.2 [+ or -] 0.4     0
                                       (0.6-1.8)
               Cyprinidon              3.1 [+ or -] 1.1     1
                 variegatus            (1.1-4.8)
               Diapterus auratus       10.9                 0
               Floridichthys carpio    7.8                  0
               Fundulus grandis        11.1 [+ or -] 6.9    0
                                       (4.2-17.9)
               Gobionellus             0.5 [+ or -] 0.2     0
                 boleosoma             (0.2-1.2)
               Gobiosoma bosc          0.6 [+ or -] 0.1    13
                                       (0.3-1.0)
               Gobiosoma robustum      0.5 [+ or -] 0.2     1
                                       (0.1-1.5)
               Haemulon                1.1 [+ or -] 0.2     0
                 flavolineatum         (0.1-3.0)
               Lagodon rhomboides      1.8  [+ or -] 1.1    3
                                       (0.1-8.3)
               Lucania parva           0.3 [+ or -] 0.1     0
                                       (0.1-0.5)
               Lutjanus griseus        6.5 [+ or -] 3.0     1
                                       (0.6-21.3)
               Mugil cephalus          13.4 [+ or -] 0.6    0
                                       (12.8-14.0)
               Mugil curema            16.0                 0
               Opsanus tau             7.8 [+ or -] 2.3     4
                                       (0.2-13.3)
               Paralichthys albigutta  1.1                  0
               Paralichthys
                 lethostigma           0.4                  0
               Poecilia latipinna      2.1 [+ or -] 0.4     1
                                       (1.6-3.0)
               Sygnathus scovelli      0.2 [+ or -] 0.1     0
                                       (0.1-0.4)

Phylum         Species                 7/04  8/04  10/04  11/04

Echinodermata  Axiognathus              0     0      0      0
                 squamatus
               Ophionereis              0     0      1      1
                 reticulata
Annelida       Phyllodoce fragilis      0     0      1      2
Mollusca       Boonea impressa          0     0      1      0
               Cerithiopsis             3     0      7      1
                 emersoni
               Cerithiopsis greeni      0     0      0      0
               Cerithium atratum        0     0      0      0
               Doriopsilla pharpa       0     0      2      0
               Eupleura caudata         0     0      1      0

               Littorina irrorata       0     0      0      0

               Nassarius vibex          4     12    11      5

               Pyrgocythara             4     0      6      0
                 plicosa
               Terebra salleana         0     0      0      0
               Thais haemastoma         0     0      2      0
                 floridana
               Urosalpinx cinerea       3     2      3      2

Arthropoda     Alpheus                 79    98    180    299
                 heterochaelis
               Callinectes sapidus      0     0      9     30

               Clibanarius vittatus     0     0      0      0

               Eurypanopeus            257   100    71     78
                 depressus
               Eurytium limosum         0     0      1      1

               Heterocrypta granulate   0     0      0      0
               Libnia dubia             0     0      0      0

               Menippe                  1     0      0      1
                 mercenaria
               Palaemonetes             0     2     14     28
                 vulgaris
               Panopeus herbstii       72     51    24     28

               Penaeus duorarum         3     9      5      3

               Petrolisthes armatus    54    29      9     15

               Rhithropanopeus          6    17     26     17
                 harrisii
               Squilla empusa           0     0      0      0
Chordata       Archosargus              1     1      7      0
                 probate-cephalus
               Bairdiella chrysoura     0     0      3      0

               Bathygobius soporator    0     0      0      0
               Chasmodes saburrae       0     0      1      3

               Cyprinidon               0     0      0      1
                 variegatus
               Diapterus auratus        0     1      0      0
               Floridichthys carpio     1     0      0      0
               Fundulus grandis         0     0      0      1

               Gobionellus              0     1     18     19
                 boleosoma
               Gobiosoma bosc          23    24    31     165

               Gobiosoma robustum       3    12    49     139

               Haemulon                 0     0      0      0
                 flavolineatum
               Lagodon rhomboides       1     2      0      1

               Lucania parva            0     0      0      5

               Lutjanus griseus         0     1      1     10

               Mugil cephalus           0     1      0      0

               Mugil curema             0     0      0      0
               Opsanus tau              1     5      0      5

               Paralichthys albigutta   0     0      0      0
               Paralichthys
                 lethostigma            0     0      0      0
               Poecilia latipinna       0     2      0     75

               Sygnathus scovelli       0     0      0      0

Phylum         Species                 12/04 1/05  2/05   3/05

Echinodermata  Axiognathus              0     0      0      0
                 squamatus
               Ophionereis              0     0      0      1
                 reticulata
Annelida       Phyllodoce fragilis      0     0      0      0
Mollusca       Boonea impressa          0     0      0
               Cerithiopsis             5     0      2      0
                 emersoni                                   1
               Cerithiopsis greeni      0     0      0      1
               Cerithium atratum        0     0      0      0
               Doriopsilla pharpa       0     2      0      7
               Eupleura caudata         0     0      1      0

               Littorina irrorata       2     0      0      0

               Nassarius vibex         10     8      1      8

               Pyrgocythara             6     6      4     13
                 plicosa
               Terebra salleana         1     0      0      0
               Thais haemastoma         0     0      0      0
                 floridana
               Urosalpinx cinerea       2     0      1      3

Arthropoda     Alpheus                370   278    210    302
                 heterochaelis
               Callinectes sapidus      9     11     4      6

               Clibanarius vittatus     0     0      0      0

               Eurypanopeus           112     45    14     34
                 depressus
               Eurytium limosum         0     0      0      1

               Heterocrypta granulate   0     0      0      0
               Libnia dubia             0     0      0      0

               Menippe                  0     0      0      0
                 mercenaria
               Palaemonetes           261     52    92     66
                 vulgaris
               Panopeus herbstii       59     47    21     48

               Penaeus duorarum         6     5      0      0

               Petrolisthes armatus    36     16     6     14

               Rhithropanopeus         46     11    12     50
                 harrisii
               Squilla empusa           0     0      0      0
Chordata       Archosargus              0     4      0      0
                 probate-cephalus
               Bairdiella chrysoura     0     0      0      0

               Bathygobius soporator    1     0      0      0
               Chasmodes saburrae       1     0      0      0

               Cyprinidon               1     0      0      0
                 variegatus
               Diapterus auratus        0     0      0      0
               Floridichthys carpio     0     0      0      0
               Fundulus grandis         0     0      1      0

               Gobionellus              3     3      0      1
                 boleosoma
               Gobiosoma bosc         228     62    47     54

               Gobiosoma robustum      27     6      3      4

               Haemulon                 0     0      0      0
                 flavolineatum
               Lagodon rhomboides       0    34     19     20

               Lucania parva            1    11      0      5

               Lutjanus griseus         2     4      0      2

               Mugil cephalus           1     0      0      0

               Mugil curema             1     0      0      0
               Opsanus tau              0     1      0      3

               Paralichthys albigutta   0     0      0      0
               Paralichthys
                 lethostigma            0     0      0      1
               Poecilia latipinna      23     6      2      0

               Sygnathus scovelli       0     0      0      0

Phylum         Species                 4/05  5/05  6/05

Echinodermata  Axiognathus              0     1      0
                 squamatus
               Ophionereis              0     0      0
                 reticulata
Annelida       Phyllodoce fragilis      0     0      0
Mollusca       Boonea impressa
               Cerithiopsis             0     0      0
                 emersoni               2     2      0
               Cerithiopsis greeni      0     0      0
               Cerithium atratum        0     0      5
               Doriopsilla pharpa       3     2      2
               Eupleura caudata         0     0      1

               Littorina irrorata       0     0      0

               Nassarius vibex          5     8      4

               Pyrgocythara             4     0      1
                 plicosa
               Terebra salleana         0     0      0
               Thais haemastoma         0     0      0
                 floridana
               Urosalpinx cinerea       2     0      0

Arthropoda     Alpheus                247   214    158
                 heterochaelis
               Callinectes sapidus      3     1      0

               Clibanarius vittatus     1     1      0

               Eurypanopeus            19     11    15
                 depressus
               Eurytium limosum         0     1      0

               Heterocrypta granulate   0     1      0
               Libnia dubia             0     1      1

               Menippe                  2     0      0
                 mercenaria
               Palaemonetes            18    44     32
                 vulgaris
               Panopeus herbstii       38    33     43

               Penaeus duorarum        40    56     18

               Petrolisthes armatus     9     4      9

               Rhithropanopeus         15    13     30
                 harrisii
               Squilla empusa           0     0      1
Chordata       Archosargus              0     3      2
                 probate-cephalus
               Bairdiella chrysoura     0     0      1

               Bathygobius soporator    0     0      0
               Chasmodes saburrae       0     0      1

               Cyprinidon               0     0      0
                 variegatus
               Diapterus auratus        0     0      0
               Floridichthys carpio     0     0      0
               Fundulus grandis         0     0      0

               Gobionellus              2     0      7
                 boleosoma
               Gobiosoma bosc          28    32     29

               Gobiosoma robustum      12     3      8

               Haemulon                 6    25      3
                 flavolineatum
               Lagodon rhomboides      29    20     19

               Lucania parva            4    47     11

               Lutjanus griseus         1     3      0

               Mugil cephalus           0     0      0

               Mugil curema             0     0      0
               Opsanus tau              5     8      8

               Paralichthys albigutta   1     0      0
               Paralichthys
                 lethostigma            0     0      0
               Poecilia latipinna       0     0      0

               Sygnathus scovelli       0     3     13

TABLE 6.
Three-factor nested ANOVA comparing species richness of
motile species in lift nets. Factors were reef type (dead margin
or reference; fixed), site nested within reef type (random), and
month (fixed).

Source             df    Mean Square     F     Significance

Reef type            1      0.003      0.000      0.985
Site (Reef type)     4      8.019      1.574      0.181
Month               11     37.699      9.340     <0.001
Residual           343

TABLE 7.
Three-factor nested ANOVA comparing density of motile species in
lift nets. Factors were reef type (dead margin or reference; fixed),
site nested within reef type (random), and month (fixed).

Source             df    Mean Square     F      Significance

Reef type           1        356.001   0.281       0.624
Site (Reef type)    4       1267.778   4.430       0.002
Month              11       2379.484  10.278      <0.001
Residual           343

TABLE 8.
Three-factor nested ANOVA comparing total sediment loads
collected per month at lift net sites. Factors were reef type (dead
margin or reference; fixed), site nested within reef type (random),
and month (fixed).

Source             df    Mean Square     F     Significance

Reef type           1    317305.223    1.961      0.234
Site (Reef type)    4    161861.650    3.357      0.011
Month              11    124938.063    2.624      0.004
Residual           199

TABLE 9.
Three-factor nested ANOVA comparing silt/clay fractions collected
per month at lift net sites. Factors were reef type (dead margin or
reference; fixed), site nested within reef type (random), and
month (fixed).

Source             df    Mean Square     F     Significance

Reef type           1    39.068        0.687      0.454
Site (Reef type)    4    56.862        0.871      0.482
Month              11    409.454       9.004      <0.001
Residual           199