ENHANCEMENT OF RECRUITMENT AND NURSERY FUNCTION

BY HABITAT CREATION IN PENSACOLA BAY, FLORIDA

by

Carrie Shannon Tomlinson Stevenson

B.S., Samford University, 1998

A thesis submitted to the Department of Biology College of Arts and Sciences The University of West Florida In partial fulfillment of the requirements for the degree of Master of Science

2007 © 2007 Carrie Shannon Tomlinson Stevenson

ii The thesis of Carrie Shannon Tomlinson Stevenson is approved:

Barbara F. Ruth, M.S., Committee Member Date

Philip C. Darby, Ph.D., Committee Member Date

Richard A. Snyder, Ph.D., Committee Chair Date

Accepted for the Department:

George L. Stewart, Ph.D., Chair Date

Accepted for the College:

Jane S. Halonen, Ph.D., Dean Date

Accepted for the University:

Richard S. Podemski, Ph.D., Dean of Graduate Studies Date

iii ACKNOWLEDGMENTS

Special thanks go to all of the volunteers who assisted me with hours of seining, identifying, collecting, and net cleaning including A. MacWhinnie, S. Bowen, A.

Bloaha, A. Schrift, J. DuPree, J. Liddle, C. Thompson, C. Power, B. Klein, L.

Pennington, C. Seltrecht, T. Chapman, C. Cox, T. Alvarez, R. Ehlers, S. Marshall, M.

Diller, N. Koch, J. McDonald, J. Cevarny, L. Cates, T. Trent, and W. Adams­Riley.

Greatest thanks to my advisor and committee members for their support, advice, and patience, as well as to Dr. Patterson and Dr. Pomory for assistance with statistical analysis. To my co­workers and supervisors at the University of Florida/Escambia

County Extension Service and Department of Environmental Protection, my deepest appreciation for equipment and encouragement, as well as allowing me the time to work on this project. Enormous thanks to my parents for accountability, confidence, and repeatedly asking me, “How’s your thesis going?” Most of all, this project is dedicated to my husband, son, and daughter for sharing me with UWF and for encouragement, help, and tolerance of all the odd hours and years it took to complete this undertaking.

iv TABLE OF CONTENTS

Page

ACKNOWLEDGMENTS ...... iv

LIST OF TABLES ...... vi

LIST OF FIGURES...... viii

ABSTRACT...... x

CHAPTER I. ESTUARINE HABITAT VALUE...... 1 A. Salt Marshes ...... 2 B. Seagrasses...... 4 C. Oyster Reefs...... 5 D. Open Bottom ...... 6 E. Habitat Diversity and Complexity...... 7 F. Restoration and Ecological Engineering...... 11

CHAPTER II. STUDY SITE DESCRIPTION ...... 17

CHAPTER III. METHODS ...... 22

CHAPTER IV. RESULTS ...... 27 A. Species Abundance ...... 29 B. Community Structure...... 55 C. Species Richness...... 58 D. Size...... 61 E. DEP Sampling Results ...... 71

CHAPTER V. DISCUSSION ...... 79

REFERENCES...... 88

APPENDIXES ...... 102 A. Map of FDEP Water Quality Sampling Locations ...... 103 B. Copyright Permission Letter...... 105 v LIST OF TABLES

Table Page

1. Timeline of Construction Activity and Sampling at Study Sites ...... 23

2. Water Quality Data Collected by FDEP ...... 28

3. Water Visibility Data Collected by FDEP...... 29

4. Species Collected in This Study ...... 30

5. Rank Order Chart for Four Most Common Species of Fish and Most Common Crustacean ...... 38

6. Comparison of Overall Abundance Data for the Frequently Occurring Species Between Sites by Paired Two Sample t Test for Means...... 40

7. Rank Order for Infrequently Occurring Species at Site 1...... 48

8. Rank Order for Infrequently Occurring Species at Site 2...... 50

9. Comparison of Four Infrequently Occurring Species Between the Sampling Sites by Paired Two­Sample t Test For Means ...... 54

10. Average Dissimilarity Between Habitats...... 57

11. Species Richness and Diversity...... 59

12. Comparison of Total L. xanthurus (Spot) by Size Class Between the Sampling Sites by Paired Two Sample t Test for Means ...... 62

13. Comparison of Total M. cephalus (Striped Mullet) by Size Class Between the Sampling Sites by Paired Two Sample t Test for Means ...... 64

14. Comparison of Total L. rhomboides (Pinfish) by Size Class Between the Sampling Sites by Paired Two Sample t Test for Means...... 66

vi 15. Comparison of Total M. peninsulae (Tidewater Silverside) by Size Class Between the Sampling Sites by Paired Two Sample t Test for Means...... 68

16. Species Collected During DEP Sampling (February­August 2005), Abundance and Percentage of Total Designated by Site ...... 72

17. Summary Table of Statistical Analysis for Four Dominant Species...... 78

vii LIST OF FIGURES

Figure Page

1. Study area in relation to the greater Gulf of Mexico region ...... 17

2. The sampling sites along the shoreline of Pensacola Bay as seen in preproject conceptual design map for Project GreenShores...... 19

3. Aerial photo of Sites 1 and 2...... 20

4. Timeline of overall faunal abundance by site ...... 36

5. Comparison of total faunal abundance between sites by sampling date ...... 37

6. The total abundance of dominant fish species recovered at the sampling locations over the entire course of the study...... 41

7. Difference in total abundance of all species in Site 1 as a percentage difference from total abundance at Site 2 ...... 42

8. Leiostomus xanthurus (Spot) abundance comparison ...... 44

9. Mugil cephalus (Striped mullet) abundance comparison ...... 44

10. Menidia peninsulae (Tidewater silverside) abundance comparison ...... 44

11. Lagodon rhomboides (Pinfish) abundance comparison...... 44

12. Callinectes sapidus (Blue crab) abundance comparison ...... 46

13. Comparative abundance for all infrequently occurring species...... 52

14. Comparison of abundance for four infrequently occurring species ...... 53

15. 2­D Multi­dimensional scaling plot representing analysis of similarity between Site 1 and Site 2 community structure ...... 55

viii 16. Species richness comparison using mean number of species captured during repeated hauls ...... 60

17. L. xanthurus abundance for Class 1 (0­4.5 cm) ...... 63

18. L. xanthurus abundance for Class 2 (4.5­9.5 cm) ...... 63

19. L. xanthurus abundance for Class 3 (9.5­20 cm) ...... 63

20. M. cephalus abundance for Class 1 (0­4.5 cm) ...... 65

21. M. cephalus abundance for Class 2 (4.5­9.5 cm) ...... 65

22. M. cephalus abundance for Class 3 (9.5­20 cm) ...... 65

23. L. rhomboides abundance for Class 1 (0­4.5 cm)...... 67

24. L. rhomboides abundance for Class 2 (4.5­9.5 cm) ...... 67

25. L. rhomboides abundance for Class 3 (9.5­14.5 cm)...... 67

26. M. peninsulae abundance for Class 1 (0­4.5 cm) ...... 70

27. M. peninsulae abundance for Class 2 (4.5­9.5 cm) ...... 70

28. M. peninsulae abundance for Class 3 (9.5­14.5 cm) ...... 70

29. Comparison of species abundances from DEP sampling in 2005; species selected for comparison to 2002­2003 study ...... 74

30. Total abundance comparison by date for L. rhomboides (Pinfish) in DEP sampling...... 75

31. Total abundance comparison by date for L. xanthurus (Spot) in DEP sampling ...... 76

32. Total abundance comparison by date for M. peninsulae (Tidewater silverside) in DEP sampling...... 77

ix ABSTRACT

ENHANCEMENT OF RECRUITMENT AND NURSERY FUNCTION BY HABITAT CREATION IN PENSACOLA BAY, FLORIDA

Carrie Shannon Tomlinson Stevenson

Urban impacts to estuarine nursery habitats can limit larval recruitment affecting fisheries production and carrying capacity. A community­sponsored habitat creation effort, Project GreenShores, in Pensacola Bay, Florida, USA, consists of a limestone oyster reef/breakwater placed seaward of intertidal areas planted with Spartina alterniflora. For this thesis, fish and epibenthic crustacean populations were sampled monthly using a 15.24 m beach seine for fifteen months during and after placement of the reefs and intertidal marsh to monitor changes. The study used an adjacent open water area separated by a point of land with similar pre­project characteristics to the marsh creation area as a control. Dominant fish and crustacean species in both locations were Mugil cephalus, Leiostomus xanthurus, and Callinectes sapidus. Overall, there were statistically significant differences between abundance of frequently occurring species and the community structures in Sites 1 and 2. Diversity was nearly indistinguishable between sites, but species richness was higher within the developed site. Fish size was similar between the sites and was consistent with expected presence

x of juvenile fish based on seasonal spawning patterns and net avoidance capability of larger fish. The results are relevant to communities and fisheries managers considering investments in large­scale habitat development projects.

xi CHAPTER I

ESTUARINE HABITAT VALUE

Estuaries are some of the most productive ecosystems on earth and over 90% of saltwater species harvested in the Gulf of Mexico and South Atlantic region spend a portion of their life cycle in them (Minello, Zimmerman, & Klima, 1987; Dawes, 1998).

The basis of this productivity lies in part with the diversity and complexity of habitat types included within estuaries. This study examines the complexity and habitat issue by the analysis of open water fish and crustacean populations associated with the creation of integrated oyster/rock reef and intertidal marsh islands separated by subtidal channels.

Estuaries contain essential habitats for many fish and invertebrate species, particularly juveniles. Salt marshes, seagrasses, and oyster reefs are examples of such habitats, providing refuges, foraging grounds, and nursery areas (Williamson, King, &

Maher, 1994; Chapman, Chapman, & Chandler, 1996; Peterson, Comyns, Hendon,

Bond, & Duff, 2000). Particular habitats within estuaries, therefore, recruit juveniles and allow for growth and survival into adulthood (Minello, Able, Weinstein, & Hays,

2003). Habitats with structural complexity provided by the presence of underwater and emergent vegetation or hard reef can shelter small fish from predators and provide substrate for epiphytic food sources (Williamson et al.; Hindell, Jenkins, & Keough,

2000; Byström, Persson, Wahlström, & Westman, 2003). The high energy gain possible

1 in a vegetated area, coupled with protection from predators, can make areas encompassing structure highly productive sites (Baltz, Fleeger, Rakocinski, & McCall,

1998). This property is illustrated by a study from Minello and Rozas (2002), who found a direct relationship between vegetated intertidal area and increased brown shrimp and blue crab production. Each type of estuarine habitat has particular advantages to various species utilizing the area and may vary within species depending on developmental stage.

Salt Marshes

Tidal salt marshes are important habitats for nutrient cycling, primary production, and production of fish, crustaceans, and macroinvertebrates within estuarine systems

(Broome, 1990; Rozas & Minello, 1998). Stable isotope studies have been used to describe the structure of salt marsh food webs and complex interactions between organic matter and macrofauna (Fry & Peterson, 1987; Peterson & Howarth, 1987), reinforcing the role of marshes in estuarine productivity. The extensive root systems of salt marshes allow them to serve as coastal buffers and their ability to trap sediments and take up nutrients improves water quality (Reed, 1989; Piazza, Banks, & La Peyre, 2005).

While salt marshes can be found worldwide (Mitsch & Gosselink, 2000), most research on the ecological role of salt marshes has been conducted in the United States, particularly in the Southeastern Atlantic and Gulf Coasts (Connolly, 1999). Many of these studies focus on the frequent use of this habitat by fish and decapod crustaceans

(Minello & Zimmerman, 1992; Minello, Zimmerman, & Medina, 1994; Micheli &

Peterson, 1999) due to their importance as nursery areas (Rozas & Minello, 1998; Rozas

& Zimmerman, 2000; Crinall & Hindell, 2004). The density of vegetation within salt

2 marshes provides shelter for juvenile nekton while the shallow water excludes larger predators (Chapman et al., 1996; O’Connell, Cashner, & Schieble, 2005).

Sampling for mobile organisms within these vegetated systems can be difficult

(Rozas & Minello, 1997; Connolly, 1999) and the diversity of methods used to study nekton use can complicate comparisons between studies. Sampling tools and methods include seines (Whaley, Burd, & Robertson, 2007), trawls (O’Connell et al., 2005), flume weirs (Connolly), drop samplers (Rozas & Minello, 1998; Meng, Cicchetti & Chintala,

2004), and fyke nets (Cardinale, Brady & Burton, 1998; Crinall & Hindell, 2004). Tidal creeks and flats within the marsh are generally easier to sample and are also used frequently by nekton (Minello et al., 1994), so many studies have focused on these areas.

Tidal creeks within marshes provide a connection to the open bay for flushing to maintain salinity levels and a means of escape for fish during low tide (Minello et al.,

1987; Cardinale et al., 1998). These natural channels provide a conduit for marine life and create an extensive network of edge throughout a marsh system (Mense & Wenner,

1989; Minello et al., 1994; Desmond, Zedler, & Williams, 2000). Edges in salt marshes are important structural elements for fish and crustaceans, providing both food resources and refuge from open water predators (Chapman et al., 1996; Desmond et al.; Bologna &

Heck, 2002; Teal & Weinstein, 2002). Teal and Weinstein observed fish at the margin of

Spartina alterniflora (Saltmarsh cordgrass) and open water and found that habitat value decreases as fish leave the marsh with a positive relationship between higher fish catch numbers and edge habitat. This relationship was found whether the fish went deeper into the middle of the marsh or further out into open water (Teal & Weinstein; Minello, et al.,

2003).

3 Seagrasses

While salt marshes provide intertidal habitat, seagrass beds are submerged vegetated habitats. Seagrasses are sensitive to a number of anthropogenic effects including boat propeller dredging, net trawling, and thermal pollution as well as natural phenomena such as tropical storms and overgrazing (Dawes, 1998). Water clarity is crucial for submerged vegetation due to its reliance on unimpeded light penetration for photosynthetic activity. Seagrasses stabilize loose sediment, dissipate wave energy, and provide a structural refuge for biota. Seagrasses may also serve as a hydraulic seine increasing residence time for floating larvae. This effect results in the buildup of an important food source accumulating mobile taxa to edges, allowing them to recruit and mature in the grassbeds (Rozas & Minello, 1998). The nursery function and predation refuge in seagrasses is comparable to that of salt marshes (Parrish, 1989; Rozas &

Minello; Flynn & Ritz, 1999). Proximity of grassbeds to differing habitats and physical structure of seagrasses enhances utilization by diverse species as well (Oviatt & Raposa,

2000). Jenkins and Sutherland (1997) found that within seagrass beds fish abundance increased with the width of leaf blades. Bologna and Heck (2002) found the vertical structure of algae and seagrass added surface area and therefore more usable habitat when compared to unvegetated sediments.

Seagrass serves as substrate for epiphytes, a vital food source for many marine species (Short, Burdick, Short, Davis, & Morgan, 2000; Hindell et al., 2000; Heck, Able,

Fahay, & Roman, 1989). In addition to providing ephiphytic food sources, some fishes, urchins (Short et al.) and endangered species including West Indian manatees

4 (Trichechus manatus) and green sea turtles (Chelonia mydas) depend on seagrass blades directly for food (Williams, 1988; Provancha & Hall, 1991; Thayer, Bjorndal, Ogden,

Williams, & Zieman, 1984).

Oyster Reefs

The value of oyster reefs in the estuarine system has been recognized for some time (Möbius, 1877) due to their high productivity and physical structure for biota within otherwise unconsolidated sediment environments (Piazza et al., 2005). Coen and

Luckenbach (2000) listed as important functions of oyster reefs a) their ability to filter and purify water, b) stabilize sediment, and c) provide a refuge for species not found in sandy bottom habitats. Oyster reefs are important in estuarine biogeochemistry because they utilize tidal energy carrying suspended particulate matter to create oyster biomass and shell reefs, as well as concentrate and recycle nutrients (Dame & Patten, 1981;

Nestlerode, Luckenbach, & O’Beirn, 2007).

The increased structural complexity of oyster reefs due to the intersitial space between shells and clusters of shells (Meyer & Townsend, 2000) provides habitat for numerous species. Posey, Powell, Alphin, and Townsend (1999) found that both primary reef residents and transients use the reefs for foraging. They showed oyster reefs were important Palaemonetes pugio (Grass shrimp) habitat; the shrimp were facultative reef residents who used the reefs for refuge when hunted, but left the area when herbivores such as Mugil cephalus (Striped mullet) were present. Opsanus beta (Gulf toadfish) and

Gobiesox strumosus (Skilletfish) are exemplary resident fish species that use oyster reefs and dead shells to lay eggs. In a comparative study of three estuarine habitat types, Coen

5 and Luckenbach (2000) found that oyster reefs contained twice the number of decapod species found in seagrasses and 15 times that of marshes. In created oyster reefs, Meyer and Townsend attributed high densities of sessile and mobile macrofauna (particularly crab species) to their structural complexity and ability to reduce turbidity.

Open Bottom

Open bottom habitats typically have the lowest nekton density when compared with marshes, seagrass beds, or reefs (Rozas & Minello, 1998; Jenkins & Wheatley, 1998) and their value is often overlooked relative to other estuarine habitats. Shallow water benthos can be as productive or more productive than the water column and is critical habitat for some small fish and many larger nekton (Hindell et al., 2000; Byström et al.,

2003). Mud flats, for example, may support micro and macroalgae and harbor shellfish, annelids, and other infauna (Rozas & Minello; Short et al., 2000). These organisms function as primary producers, deposit feeders, and filterers, producing and cycling energy to higher trophic levels (Thorpe et al., 1997; Butts & Lewis, 2002). Open water is half of the “edge” component found to be crucial in numerous studies (Minello, et al.,

1994; Hindell et al.; Bologna & Heck, 2002), and unvegetated channels may be important for migration and spawning of larger nekton (Minello et al., 1987). Planktonic food sources in marshes have been shown to increase in density with proximity to open water

(Cardinale et al., 1998). Unvegetated bottoms adjacent to vegetated habitat are often undervalued as ecotones providing critical habitat and are thus more vulnerable to dredging and human influence than wetlands and seagrasses (Oviatt & Raposa, 2000;

Meng et al., 2004; Gratwicke & Speight, 2005). A paucity of research exists on the value

6 of the open bottom component. Those studies done in marsh channels and mud flats, for example, are often undertaken not to examine importance of open bottom but to focus on the value of adjacent marsh (Connolly, 1999).

Habitat Diversity and Complexity

Studies examining the importance of habitat edges have highlighted the importance of the proximity of several different kinds of habitat for enhancing estuarine biodiversity and providing critical habitat to a variety of juvenile fish. Rugosity, a measure of surface topography analyzed by optical intensity video, has positively correlated complexity with increased species richness, diversity, and abundance

(Shumway, Hofmann, & Dobberfuhl, 2007). In an Australian study Jenkins and Wheatley

(1998) observed structure, diversity, and recruitment of fish in seagrass, reef­algal, and unvegetated habitats. They found seagrass and reef had similar fish assemblages and larger populations than unvegetated sand, demonstrating that habitats incorporating structure supported higher population densities and species richness. The more diverse spacing (i.e. complex structure) a habitat possesses, the better it accommodates larger fish and smaller prey, thus leading to higher species diversity in a given area (Meng et al.,

2004; Gratwicke & Speight, 2005; Ribeiro, Almeida, Araújo, Biscoito, & Freitas, 2005).

Chapman et al. (1996) also found a positive relationship between species richness, low dissolved oxygen, and structural complexity especially in rocky crevices and the submerged and emergent vegetated areas along shorelines.

Many species do not select just one form of habitat and often a single ecotone is not valued over all others (Rozas & Zimmerman, 2000), emphasizing the importance of

7 the proximity of diverse habitat types (Gratwicke & Speight, 2005) and linkages between them for maximum recruitment and productivity (Irlandi & Crawford, 1997; Micheli &

Peterson, 1999; Oviatt & Raposa, 2000). Pelagic recruits often live in grassbeds adjacent to reefs, and Parrish (1989) found the proximity of these habitat types enhanced recruitment by providing refuge until space availability or fish size allowed migration to the reef. He suggested more studies on the “effects of proximity of different habitat types” to clarify their means of interaction and roles in the greater ecology of estuarine systems.

The premise that increased structure equals increased species abundance and richness has been widely accepted, but a handful of studies have shown contrary results.

Bartholomew (2002) created an index describing habitat complexity and the relationship between prey size and space available for hiding and found that increased cryptic space availability reduced species richness but noted the possibility that this finding may have been the result of hidden prey. Glancy, Frazer, Cichra, and Lindberg (2003) emphasized the importance of structure in their comparison of the relative habitat value of oyster reefs, seagrasses, and marshes. At an alpha diversity level their study showed a similarity in species composition in marshes and seagrasses, while oyster reefs harbored a different community structure. Jenkins and Sutherland (1997) found significantly more species richness in grass than reef and believed the “structure only” hypothesis was incorrect.

They believed the necessary prey and food sources would be found within a vegetated area, but eventually feeding strategies would be the limiting factor in determining habitat selection. Bologna and Heck (2002) also investigated this theory but, after sampling in seagrass patch edges and interiors, found the less densely packed edges of seagrass were

8 more productive and yielded higher fish catches than the dense interior patches. A similar finding in freshwater wetlands showed species richness and fish abundance decreased when measured within the marsh and further from open water (Cardinale et al.1998) relative to the marsh edge. Some faunal species prefer sandy bottoms to reef or vegetated structure yet utilize the edges of vegetated or structural habitats for foraging (Jenkins &

Wheatley, 1998; Hindell et al., 2000). Many of these studies support the idea that ecotones encompassing several types of habitat complexity will be more productive than those with little variation.

Predatory pressure also plays a key role in forming essential habitat for juvenile estuarine species. Chapman et al. (1996) found that nursery function of wetlands is fundamental because structural complexity can exclude larger fish, whereas open water does not have those limitations. Structure in the form of a “flexible barrier” (seagrasses, marsh) or physical impediment (rock, reef) may create some difficulty and potential for energy loss for predatory fish attempting to swim through it (Bartholomew, 2002). In addition, the lower dissolved oxygen levels found in dense wetlands prevent large predatory fish from utilizing wetlands as forage areas. Hindell et al. (2000) looked at small fish assemblages over unvegetated sand and seagrass and found piscivory decreased as habitats became more complex, although predation varied significantly with tidal and diel cycles. Even for species that prefer to feed in open water, the proximity of grassbeds, marsh, or reef provides a refuge from larger predators (Hindell et al.; Ribeiro et al., 2005).

Predator strategy and size play key roles in interactions within high complexity habitats. Flynn and Ritz (1999) found that resident reef fish using a “hide and wait”

9 approach were more successful in catching prey while the maneuverability of active searchers was often reduced in highly complex habitats. Habitats normally considered the lowest predation risk may change based on the sizes of prey and predators present. A study by Byström et al. (2003) found that when predators of a certain size moved into a marsh, the complex habitat normally assumed to be low risk shifted to higher risk and sent young of the year L. rhomboides (Pinfish) into open water for refuge. Similar findings have been found beyond estuarine ecology—in coral reefs a study showed prey preferred reefs where predators had been excluded regardless of structural complexity, although when predators were reintroduced recruitment was greater on more complex reefs (Almany, 2004).

The substantial body of evidence showing that proximity to structure and habitat complexity increases estuarine production (Irlandi & Crawford, 1997; Pittman, McAlpine,

& Pittman, 2004) has supported numerous efforts to preserve existing habitats, restore damaged habitats and even to create new habitats (Minello et al., 1987; Meyer &

Townsend, 2000; Nestlerode et al., 2007). When attempting to restore lost estuarine habitats or create new ones, an integrated approach, i.e. incorporating habitat diversity, may be the most effective means of enhancing biodiversity and production (Parrish, 1989;

Bertness & Leonard, 1997; Whaley et al., 2007).

10 Restoration and Ecological Engineering

Wetland plantings have been documented in Europe and the United States from as long ago as the 1920’s and 1930’s to stabilize shores, reclaim land, or reduce channel siltation. These activities have increased in the recent past (Broome, 1990), and governments and private entities have spent millions of dollars annually reestablishing or creating wetlands to recover marsh habitat losses (Lewis, 1990). Restoration ecology as a specific scientific discipline has progressed substantially since the 1990’s (Urbanska,

1999) in response to a need for evaluation of efficacy and efficiency in use of public resources to this end. In addition to scientific evidence of the value of estuarine habitats, public awareness of marsh, seagrass, and oyster reef habitats’ importance to coastal ecosystems has increased significantly, and support for attempts to restore and create habitats has grown (Chabreck, 1990). Besides enhancing ecosystem processes, benefits of healthy estuarine habitats include eco­tourism and environmental education, adding to the public support for restoring large­scale areas damaged by development, poor water quality, and subsidence (Connolly, 1999; Marcus, 2000; Florida Department of

Environmental Protection [FDEP], 2002; Lefeuvre & Bouchard, 2002). In degraded areas, marsh creation can contribute to an overall ecological boost and addition of new species due to physical proximity of wetlands (Snodgrass, Bryan, Lide, & Smith, 1996).

The value of these created marshes relative to natural marsh systems has been the subject of considerable debate. Callinectes sapidus (Blue crab), used as an indicator of salt marsh habitat value, showed a positive response to restored marshes, moving into the restored areas quickly and at larger sizes than those utilizing an existing reference marsh

11 (Jivoff & Able, 2003). The restored area appeared to enhance recruitment and serve as a protective refuge for molting. Similarly, macrofaunal density was found to be higher in a created Salicornia (Glasswort) marsh relative to a natural marsh, although human activity impacted the reference marsh (Talley & Levin, 1999). Significant transport of production from a restored marsh was found for Fundulus grandis (Gulf killifish) where fish entering the marsh had stomachs 40% full while those leaving had stomachs 60­80% full

(Teal & Weinstein, 2002). Sheridan (2004) noted that newly introduced seagrasses in an otherwise bare habitat could shelter nekton as effectively as a natural grassbed within 6 to

36 months, while settlement and faunal use of created oyster reefs has been found to exceed the density of natural reefs in periods of less than 2 years (Meyer & Townsend,

2000). A review of 36 restoration projects in the Gulf of Maine showed no detectable differences for fish assemblages between restored and existing natural marshes (Konisky,

Burdick, Dionne, & Neckles, 2006). Conversely, others have shown juvenile crustacean utilization of restored marshes was less than natural marshes, most likely due to a lack of benthic organisms and accumulated organic matter (Minello & Zimmerman, 1992;

Minello & Webb, 1993). Incorrect hydrology, poor soil quality, and stunted vegetation prevented a California wetland restoration from attracting endangered species and functioned at approximately 60% capacity of a natural reference marsh (Malakoff, 1998).

Shoreline rehabilitation and stabilization has been a major focus of wetland restoration efforts. Response to eroding shorelines has often involved installation of hard structures to stabilize sediment, such as riprap or seawalls (Haslett, 2000; Bush et al.,

2001). Two United States Fish & Wildlife Service (USFWS) studies in the Northeastern

U.S. found that approximately 25% (over 100 miles) of the Narragansett Bay (Rhode

12 Island/Massachusetts) estuary was armored with bulkheads, revetments, and seawalls, and the Peconic Estuary (New York) had 19 miles of hardened shoreline (Tiner, Begquist,

Siraco, & McClain, 2003; Tiner, Huber, Neurminger, & Mandeville, 2003). Hardening of natural shorelines leads to a significant loss of fish habitat and contributes to declining health and productivity of an estuary (Peterson et al., 2000; Piazza et al., 2005). Dredging, filling, bulkheads, and seawalls eliminate the intertidal and shallow water ecotone associated with the natural shoreline. Higher numbers of taxa have been found adjacent to natural shorelines than hardened ones, leading to a conclusion that a more diverse population of fish can thrive near a natural shoreline and marsh (Peterson et al.; Chapman,

2003; Seitz, Lipcius, Olmstead, Seebo & Lambert, 2006). In the Indian River Lagoon

(Florida) scouring associated with hardened shorelines did not affect subtidal seagrass distribution (Nielson, Eggers, & Collins, 2000). In an urban estuary in Australia with half its shoreline hardened, abundances of algae and sessile species (polychates, bivalves, sponges, and sea anemones) within the study were comparable between seawalls and natural rocky shores, but rare species and 50% of the mobile taxa were found only on natural shorelines (Chapman).

Many state environmental regulatory agencies encourage planting native emergent wetland species or seagrasses along shorelines to protect them from erosion as an alternative to hardened shoreline structures (Scheinkman, Livingston, & Knecht,

2001). The success of these small restoration projects is often contingent upon the location and wave energy surrounding the shoreline (Butts, 1998, Piazza et al., 2005).

Projects should be designed specifically for the site characteristics (Broome, 1990;

Urbanska, 1999). Vegetated shorelines have been documented to be resistant to storm

13 damage and may help accrete land (Clark, 1990; Dawes, 1998; Haslett, 2000). The ecological success of small shoreline restoration areas and larger marsh creations is often gauged as a comparison of habitat value between existing, historical marshes and the newly restored marshes (Zedler, 2000; Jivoff & Able, 2003; Konisky et al., 2006).

While the effectiveness of restored or created salt marshes in producing fish has been well documented, the question of whether an artificial reef—either completely submerged miles offshore or an intertidal oyster bed—actually serves to produce new fish populations or just attract and concentrate existing ones remains controversial. True recruitment would mean the structure provided habitat for fish that would not have survived otherwise, for larvae are generally produced in numbers greatly exceeding habitat carrying capacity (Shulman, 1984; Parrish, 1989). A reef functioning only to attract would simply collect existing fish into a more central area (Pickering &

Whitmarsh, 1996). An analysis of actual productivity requires not just high catch rates or rapid colonization but evidence of greater catch in the whole region in proportion to fishing pressure, amount of reef added, and increases in the strength of year classes

(Bohnsack, Harper, McClellan, & Hulsbeck, 1994; Pickering & Whitmarsh). The size of the reef, use by target species, and design in relation to currents are all criteria for creating a reef that serves to produce and not simply attract new fish (Ribeiro et al., 2005;

Nestlerode et al., 2007).

Many studies have examined the benefits of vegetative or reef habitat compared with open water, but very few have contrasted two open water habitats for the proximate effects of created habitat diversity and structure. Minello et al. (2003) analyzed 32 studies investigating nekton use of structure, 20 of which were located on the Gulf Coast

14 involving comparisons with open water (OW) or non­vegetated marsh edge (NVME) habitat types. Of the 32, however, none of the studies looked at OW versus OW or purely

OW versus NVME. Ten of them included these comparisons within their study but also looked at seagrass, marsh, creeks, or other biotopes at the same time (Minello et al.).

Two or more different ecotones are generally analyzed in studies of estuarine habitat restoration and involve sampling with a seine, trawl, or enclosure device.

Research efforts typically focus on fish or decapod crustaceans for species richness and abundance. In a review of 26 studies of wetland restoration sites in the 1990’s, fully half of the papers surveyed showed fish and invertebrate populations were the most widely used indicators of restoration progress (Zedler & Callway, 2000). Most fishes are highly mobile and can therefore populate a new habitat by choice quickly, and they are relatively easy to capture, identify, and enumerate. The most useful information is typically obtained by looking at species richness and dominance, the size distribution of fish within different habitat types, and gut contents (Cardinale et al., 1998; Desmond et al., 2000; Glancy et al., 2003; Able, Nemerson, & Grothues, 2004).

The long­term success of any wetland restoration or creation project cannot be judged conclusively from faunal use or plant growth within a year or so of installation.

Many projects are scrutinized based on these minimal criteria because they must meet certain goals within particular time frames based on permit requirements from regulatory agencies (Zedler, 2000). These process constraints shift focus to short­term effects rather than the long­term potential of the created system (Malakoff, 1998). Monitoring of created wetlands is generally short­term (< five years), whereas natural sites used for reference may be hundreds or thousands of years old. Within the Zedler and Callaway

15 (2000) survey only 12 of 26 restoration sites were sampled more than six times, and most were sampled over short periods immediately following restoration. The majority of the studies were sampled once or twice per year, except for a single study that sampled eight times in one year to encompass seasonal variability. Because of such limited monitoring, the researchers suggested that for the years immediately following a wetland restoration, the terms “progress” or “compliance” be used rather than “success” in the regulatory arena (Zedler & Callaway).

This study in Pensacola Bay, Florida, included 30 separate sampling events over

15 months to increase the resolution of the information gathered beyond conventional monthly or seasonal sampling regimes. Information was obtained using similar evaluation techniques for fish and invertebrates as other estuarine habitat comparison studies. This report covers the initial short term monitoring and forms a baseline for future analysis by field biologists with the FDEP.

16 CHAPTER II

STUDY SITE DESCRIPTION

The study site lies along the north­central portion of Pensacola Bay, Florida.

Pensacola Bay, the fifth large estuarine system in Florida (Butts, 1998), is located in the extreme northwestern region of Florida (Figure 1). Several rivers and numerous freshwater bayous feed the bay, with a tidal inlet to the Gulf of Mexico through

Pensacola Pass. Historical records show the bay contained extensive seagrass meadows, salt marshes, and harvestable oysters. The influences of overfishing, inadequate sewage disposal, urban stormwater runoff, industrial discharges, dredging, filling, and shoreline hardening have led to a depletion and degradation of these natural resources (Thorpe et al., 1997).

Figure 1. Study area in relation to the greater Gulf of Mexico region.

17 In the fall of 2001 the FDEP Ecosystem Restoration Section along with several other local government agencies and private donors proposed a habitat creation effort

(Project GreenShores) aimed at a) enhancing recruitment of larvae and juvenile estuarine species, b) increasing the carrying capacity of the system for fish and invertebrate populations, and c) improving water quality.

Project GreenShores involved a plan for two phases of construction (Figure 2).

Phase I, totaling 4.85 hectares, included limestone boulder breakwaters in the bay, approximately 60 m from shoreline between the Pensacola Bay Bridge and the east side of Muscogee Wharf (Figure 3). Construction of breakwaters allowed the relatively quiescent area behind the breakwater/oyster reef to support a tidal marsh along an otherwise open bay/high energy shoreline (Broome, 1990; Piazza et al., 2005). Planted emergent grasses under stress of incoming waves do not typically survive well if they are not protected during establishment (Butts, 1998). The permanent wave breaks were envisioned to become reef habitat for fish and oysters (Coen & Luckenbach, 2000; FDEP,

2002). Landward of the oyster beds, sand was pumped in from a nearby dredge spoil site at the mouth of Bayou Texar to create several large intertidal sandbars. Construction of the new marsh and oyster reef took place only within the area denoted as “Site 1” in

Figures 2 and 3 during the course of this study.

18 Spoil source

Figure 2. The sampling sites along the shoreline of Pensacola Bay as seen in preproject conceptual design map for Project GreenShores. The intertidal areas were separated from the shoreline by a 30 m channel as seen in Fig. 3. No construction activity occurred in

Site 2 during the course of this study. The source of dredge spoil used for intertidal areas is at the NE corner of diagram. Map is reprinted with permission from FDEP. Site 2 Site 1 Intertidal area

Oyster reef

Figure 3. Aerial photo of Sites 1 and 2. This view shows the actual position of the reefs,

intertidal marshes, and the approximate location of the sampling sites (stars) for this

study. Photo is reprinted with permission from FDEP.

The bars are 15­18 m wide, separated by 6 m channels, and follow the contour of

the shoreline. This technique of using dredged sand in intertidal habitat creation has

become a popular method of recycling local spoil material (Minello et al., 1994; Marcus,

2000; Teal & Weinstein, 2002). S. alterniflora was planted as 36,000 plugs within the

intertidal areas (Butts, 1998; FDEP, 2002). This species propagates sexually via seeds

and/or asexually with underground rhizomes (Lewis, 1990; Tobe et al., 1998), and is

capable of rapid colonization leading to good plant survival (Urbanska, 1999). Project

managers added Juncus roemerianus (Black needlerush) after sampling for this study was

complete and plan to add submerged aquatic vegetation Halodule wrightii (Shoal grass)

and Thalassia testudinum (Turtle grass) in the tidal creeks of the next Phase. Plans for

Phase II of the project would expand to the west of Muscogee Wharf in 2007 (Figure 2). 20 This area was used as the open shoreline control site for this study and designated “Site

2.” Using the definitions posed by Minello et al. (2003), Site 1 would be considered a combination of “open water” (OW) and “non­vegetated marsh edge” (NVME) while Site

2 is considered OW. In this instance, open water is an area, such as a shallow bay, with a sand bottom and no vegetative or hard structure. Non­vegetated marsh edge is open sand bottom within 10 m of marsh vegetation.

In the time since initial planting, the marsh grasses have remained intact through

Hurricanes Ivan (September 16, 2004, Category 3), which passed over the City of

Pensacola, and Dennis (July 7, 2005, Category 3), which passed just east of Pensacola

Bay. The created wetland was largely unaffected by hurricane winds, waves, and storm surge that partially destroyed the adjacent roadway (Looney & Hobbs, 2005).

The objectives of this study were to determine whether the addition and proximity of structure as limestone breakwater/oyster reef and marsh into a previously sand­bottom, open water area (Site 1) would result in differences in the abundance and diversity of juvenile fish and crustaceans as open water nekton when compared to the adjacent open water (Site 2) without such structural elements.

21 CHAPTER III

METHODS

A bi­monthly survey of the fish and decapod crustacean populations in both Site 1 and Site 2 was conducted from May 2002—July 2003, coinciding with the placement of the limestone breakwaters and intertidal marsh areas (Table 1). The locations of the sampling sites were 0.48 km apart but were separated by a large point of land, Muscogee

Wharf (Figures 2, 3).

Site 2 was a sand bottom with occasional oysters and debris and had no emergent littoral or submerged vegetation. Site 1 began in the same physical condition, but progressively changed as the rock reef, sand, and plants were added. At the point of commencement of standardized sampling in May 2002, half of the oyster reef was constructed at Site 1. From November 8, 2002 to January 21, 2003, dredge spoil material was pumped into the Site 1 area (30,000­40,000 cubic yards of sand). During these few months of pumping we experienced an increase in difficulty pulling the seine due to loose sand settling on the bay bottom; the net often filled up and seining would have to start again after the net was emptied. In early February 2003, the final rocks and grass planting occurred. Seining continued throughout the changes. Thirty sampling events, starting on

May 17, 2002, and ending on July 19, 2003 (15 months), were conducted to encompass the seasonal change and weather events as well as provide comparative overlap during the summers of 2002 and 2003.

22 Table 1. Timeline of Construction Activity and Sampling at Study Sites

Date Activity at Site 1

November 2001 Construction of limestone breakwater/oyster reef begun

January 22, 2002 Half of breakwater in place

May 17, 2002 Began faunal sampling (at both sites)

June 2, 2002 Sampling event

June 15, 2002 Sampling event

July 7, 2002 Sampling event

July 16, 2002 2000 plants placed along shoreline

August 3, 2002 Sampling event

August 10, 2002 Sampling event

August 20, 2002 Sampling event

September 7, 2002 Sampling event

September 21, 2002 Sampling event

October 7, 2002 Sampling event

October 19, 2002 Sampling event

November 8, 2002 Begin pumping 30,000­40,000 cubic yards of sand to create

intertidal sandbars

November 10, 2002 Sampling event

November 24, 2002 Sampling event

November 30, 2002 Sampling event Table 1 (continued). Timeline of Construction Activity and Sampling at Study Sites

Date Activity at Site 1

December 2, 2002 Sampling event

January 11, 2002 Sampling event

January 21, 2003 End pumping of sand

January 25, 2003 Sampling event

February 2, 2003 Final rocks placed at breakwater (20,000 tons)

February 3, 2003 Final grass planting on intertidal sandbars (30,000 plants

February 16, 2003 Sampling event

February 22, 2003 Sampling event

March 9, 2003 Sampling event

March 23, 2003 Sampling event

April 12, 2003 Sampling event

April 27, 2003 Sampling event

May 11, 2003 Sampling event

June 14, 2003 Sampling event

June 29, 2003 Sampling event

July 6, 2003 Sampling event

July 19, 2003 Final faunal sampling event (at both sites) Samples were taken using a 15.24 m beach seine net with 6.35 mm mesh wings and a 1.82 x 1.82 x 1.82 m bag in the middle with 3.17 mm mesh. Consistent sampling methodology was used throughout the study. Two people waded out 30.5 m offshore and pulled the net to the beach, resulting in a sample area of approximately 465 cubic meters each haul. At Site 1 seining began at the edge of an intertidal bar and ended at the shore, while Site 2 began at a marked point 30.5 m offshore and ended at the beach. Two hauls were conducted per sampling site (Figure 2). Sampling of both sites occurred within the same two­hour block of time to remove as much bias as possible from temperature, salinity, and tidal condition differences at each site. The majority of seine hauls were conducted during the afternoon at high tide.

After each haul, individual specimens were identified on site (to species level if possible), enumerated, measured (total length [cm] for fish and shrimp, carapace width for crabs [cm]), and released into the bay. Unusual species were photographed or collected for further identification. Attempts were made to release specimens alive, although young Menidia peninsulae (Tidewater silverside) and M. cephalus (Striped mullet) suffered losses due to their fragility. Sampling effort was biased towards juveniles due to the selective nature of the beach seine, but this bias was consistent between sites.

Species diversity and abundance data were analyzed statistically using Plymouth

Routines in Multivariate Ecological Research (PRIMER v5) software’s 2­way ANOSIM,

SIMPER, and DIVERSE tests, JMP (Version 5) software’s repeated measures test, and

Microsoft Excel’s paired t test and correlation analyses. Abundances were log transformed (x+1) when needed to meet homogeneity of variances and assumptions of

25 normality. Water quality data obtained from the local FDEP stations 4 and 6 (Appendix

A) by biology laboratory staff represented Sites 1 and 2 respectively. Both stations were located adjacent to large stormwater outfalls draining urban watersheds. Water quality data for the sites included turbidity, nitrogen levels, total and fecal coliform bacteria levels, temperature, dissolved oxygen, salinity, pH, and secchi depth. Sampling was conducted with a YSI multiprobe meter (water temperature, dissolved oxygen, pH, salinity). Bacterial samples were collected in autoclaved sterile plastic bottles, while turbidity, color, and total suspended solids were collected in plastic half gallon bottles.

Nutrients were collected in a 500 mL plastic bottle prepreserved with sulfuric acid. All samples were transported on ice and processed according to FDEP standard operating procedures.

Sources of error and uncontrolled variables included net snagging on bottom debris at Site 2, differences in physical ability of volunteers to pull net, and weather conditions. Attempts were made to nullify these sources as much as possible by using a consistent, debris­free area to seine and training a pool of assistants who participated frequently enough to become skilled in the methodology. Sampling dates were on weekend mornings or afternoons based on volunteer availability. Any biases were present at both sites—the same people used the net during each sampling event and hauls were conducted within one hour of each other. Inclement weather was avoided as much as possible, although the sampling event on January 4, 2003, occurred in 2­3 foot waves due to an oncoming storm.

26 CHAPTER IV

RESULTS

No significant differences existed between water temperatures, dissolved oxygen, salinity, pH, turbidity, color, or total suspended solids data collected at both sites between

June 2001 and April 2004 (Tables 2 & 3; Repeated measures ANOVA, p > 0.05 for all parameters). Water temperatures measured in Pensacola Bay during this time ranged from 10° C in January to 31° C in July (Table 2). Fecal bacterial samples taken in

October 2002 recorded levels beyond acceptable range or too numerous to count at both sites (Table 2) but indicated no real differences between sites. The lack of any significant differences between the two sampling locations suggests any differences in biota were due to the habitat creation activity at Site 1.

27 Table 2. Water Quality Data Collected by FDEP

Temp °C Temp °C DO DO Salinity Salinity pH pH FC FC

Date Site 1 Site 2 1 2 1 2 1 2 1 2

6­Jun­01 29.56 29.88 9.29 7.97 20.19 20.28 8.03 8.00 0 0

6­Jul­01 31.01 30.59 8.17 8.09 15.35 15.88 7.96 7.96 0 0

30­Jan­02 18.99 18.49 8.82 8.66 15.88 15.80 8.07 8.05 0 0

24­Apr­02 24.48 24.53 7.68 7.56 15.78 15.24 8.14 8.11 50 10

17­Jul­02 31.30 31.20 5.97 5.71 26.51 25.90 8.00 8.01 10 10

28­Oct­02 24.60 24.25 7.74 7.58 14.77 16.44 7.74 7.90 420 1Z*

27­Oct­03 23.40 23.30 7.53 7.86 22.00 21.50 8.04 8.08 70 108

21­Jan­04 10.60 11.00 7.79 7.74 19.80 19.70 7.88 7.90 2 6

21­Apr­04 21.95 21.97 7.27 8.19 19.50 19.90 7.73 7.92 134 100

Note. DO = Dissolved oxygen, FC = Fecal coliform, *Z = Too numerous to count Table 3. Water Visibility Data Collected by FDEP

Turbidity Turbidity Color Color TSS TSS

Date Site 1 Site 2 1 2 1 2

6­Jun­01 3 2 20 30 31 27

6­Jul­01 0 0 0 0 0 0

30­Jan­02 2 5 10 10 12 18

24­Apr­02 2 1 30 30 11 10

17­Jul­02 4 4 15 15 22 16

28­Oct­02 2 3 25 25 5 6

27­Oct­03 1 1 20 20 17 22

21­Jan­04 1 1 10 10 28 27

21­Apr­04 0 0 0 0 0 0

Note. TSS = Total suspended solids

Species Abundance

Out of 24,387 individual fauna collected over a 15­month period, 31 species of fish, one mollusk, and three species of decapod crustaceans were captured and identified in the two sampling areas. Of 35 species, all were commonly occurring estuarine species

(Table 4). A total of 14,256 individual fish, crustaceans or mollusks (33 out of 35 total species) were captured at Site 1, while 10,131 (29 of 35 species) were caught in Site 2.

29 Table 4. Species Collected in This Study

Phylum Mollusca

Class Gastropoda

Order Mesogastropoda

Family Littorinadae

Littorina irrorata

Phylum Arthropoda

Subphylum Crustarea

Class Crustacea

Order Decapoda

Family Paguridae

Pagarus berhardus

Family Palaemonidae

Palaemonetes pugio

Family Portunidae

Callinectes sapidus

Phylum Chordata

Subphylum Vertebrata

Superclass Osteichthyes

Class Actinopterygii Table 4 (continued). Species Collected in This Study

Order Atheriniformes

Family Atherinopsidae

Menidia peninsulae (Goode & Bean)

Order Aulopiformes

Family Synodontidae

Synodus foetens (Linnaeus)

Order Batrachoidiformes

Family Batrachoididae

Opsanus beta (Goode & Bean)

Order Beloniformes

Family Belonidae

Strongylura marina (Walbaum)

Family Hemiramphidae

Hyporhampus unifasciatus (Ranzani)

Order Clupeiformes

Family Clupeidae

Harengula jaguana (Poey)

Order Cyprinodontiformes

Family Fundulidae

Fundulus grandis (Baird & Girard)

Fundulus similis (Baird & Girard) Table 4 (continued). Species Collected in This Study

Family Cyprinodontidae

Cyprinodon variegatus (Lacepede)

Order Elopiformes

Family Elopidae

Elops saurus (Linnaeus)

Order Gobiesociformes

Family Gobiesocidae

Gobiesox strumosus (Cope)

Order Perciformes

Family Carangidae

Caranx spp.

Oligoplites saurus (Bloch & Schneider)

Trachinotus carolinus (Linnaeus)

Trachurus lathami (Nichols)

Family Gerreidae

Eucinostomus argenteus (Baird & Girard)

Family Haemulidae

Orthopristis chrysoptera (Linnaeus)

Family Mugilidae

Mugil cephalus (Linnaeus) Table 4 (continued). Species Collected in This Study

Family Sciaenidae

Leiostomus xanthurus (Lacepede)

Menticirrhus americanus (Linnaeus)

Sciaenops ocellatus (Linnaeus)

Family Sparidae

Archosargus probatocephalus (Walbaum)

Lagodon rhomboides (Linnaeus)

Order Pleuronectiformes

Family Paralichthyidae

Citharichthys macrops (Dresel)

Paralichthys albigutta (Jordan & Gilbert)

Paralichthys lethostigma (Jordan & Gilbert)

Family Cynoglossidae

Symphurus minor (Ginsburg)

Order Scorpaeniformes

Family Triglidae

Prionotus tribulus (Cuvier)

Order Siluriformes

Family Ariidae

Arius felis (Linnaeus) Table 4 (continued). Species Collected in This Study

Order Syngnathiformes

Family Syngnathidae

Syngnathus scovelli (Evermann & Kendall)

Order Tetraodontiformes

Family Diodontidae

Chilomycterus schoepfii (Walbaum)

(Froese & Pauly, 2007; Robins, Ray, & Douglass 1987; Hoese & Moore 1977) Faunal abundance from early sampling conducted during the majority of reef construction (May­September 2002) in both sites was low, but a greater overall number of fish and crustacean species were captured in Site 1 over Site 2 (Figure 4). Total abundance in Site 1 increased to the low hundreds by November 2002, peaking to several thousand in March 2003 and never dropping below 100 per sampling event through the conclusion of the study in July 2003 (Figure 5). Overall numbers in Site 2 also increased in early winter and moved into the thousands by late winter/early spring (January­March

2003) when thousands of young of the year were captured and enumerated. Construction of the reefs and planting sites were also complete at this point. In April 2003, overall numbers dropped off significantly through the summer, except for the M. peninsulae

(Tidewater silverside) population, which increased slightly. Sampling ended in mid­July

2003.

Overall abundance of individuals in May­June 2002 was significantly lower than

May­June 2003 (Site 1 p = 0.026; Site 2 p = 0.007). Fewer than ten individuals of any species were caught in either site during May and June of 2002, and were predominantly

L. rhomboides (Pinfish), E. argenteus (Spotfin mojarra), and L. xanthurus (Spot). Total faunal abundance in the same months of 2003 were 10 times the previous year’s totals in both sampling areas, and dominant species were L. xanthurus (Spot), M. peninsulae

(Tidewater silverside), L. rhomboides (Pinfish), T. carolinus (Florida pompano), and M. cephalus (Striped mullet). Low numbers of previously unseen species appeared in the summer of 2003 as well.

35 3500

3000

2500 Site 1 2000 Site 2

1500

1000

500

0

­500

Dates & activities

Figure 4. Timeline of overall faunal abundance by site. Error bars represent standard error. 4500

4000 Site 1 Site 2 3500

3000

2500

2000

1500

1000

500

0

02 2 2 2 2 2 2 2 3 3 3 03 3 3 3 7/ 5/0 /7/0 0/0 /7/0 /7/0 0/0 30/0 /4/0 5/0 2/0 3/ 7/0 4/0 /6/0 *5/1 6/1 7 8/1 9 10 11/1 11/ 1 1/2 2/2 3/2 4/2 6/1 7 ­500

Figure 5. Comparison of total faunal abundance between sites by sampling date. Error bars represent standard error. The same four fish species were most abundant by rank order for both sites (Table

5). Percentages of total fauna at Sites 1 and 2, respectively, were M. cephalus (Striped mullet; 42.21%, 39.54%), followed by Leiostomus xanthurus (Spot; 38.46%, 36.39%), M. peninsulae (Tidewater silverside; 10.72%, 19.24%), and Lagodon rhomboides (Pinfish;

3.64%, 1.12%). A comparison of the relative abundance of these four species can be seen in Figure 6. The most common crustacean, Callinectes sapidus (Blue crab; 0.73%; 0.45%) is also listed (Table 5).

Table 5. Rank Order Chart for Four Most Common Species of Fish and Most Common

Crustacean

Site 1 Site 1 Site 2 Rank Site 2 Fish Species Total % of Total Order % of total individuals total individuals

1 Mugil cephalus 6017 42.21 4006 39.54 2 Leiostomus xanthurus 5483 38.46 3687 36.39 3 Menidia peninsulae 1528 10.72 1949 19.24 4 Lagodon rhomboides 519 3.64 113 1.12 Total 13547 95.03 9755 96.29

Site 1 Site 1 Site 2 Rank Site 2 Crustacean Species Total % of Total Order % of total individuals total individuals

1 Callinectes sapidus 104 0.73 46 0.45 Total 104 0.73 46 0.45

38 No significant difference in abundance existed for repeated hauls on the same day at each site so pooled data were used for repeated measures tests. Overall faunal abundance between sites did not show any significant differences, but individual analyses of numerically dominant species did. Abundance varied seasonally with water temperature and spawning patterns and was highly correlated with a positive correlation coefficient of 0.87. The difference between total abundance at each site was calculated by dividing the total number of fish caught (by date) at Site 2 by the number at Site 1, giving the percent difference between site abundances. This data was plotted and shows a gradual increase (particularly from April to July 2003) in the difference between each site, with Site 1 having greater abundance (Figure 7).

The five most commonly captured species were analyzed by paired t test and showed highly significant differences between abundance in Site 1 and Site 2 (Table 6).

Of these five species, M. cephalus (striped mullet) had the most significantly different populations between the two sites while C. sapidus (blue crab) had the least.

39 Table 6. Comparison of Overall Abundance Data for the Frequently Occurring Species

Between Sites by Paired Two Sample t Test for Means

Species t Statistic P (T<=t) two­tailed

Mugil cephalus 3.98157 0.00042

Lagodon rhomboides 3.82024 0.00062

Leiostomus xanthurus 3.14092 0.00386

Menidia peninsulae 2.35407 0.02556

Callinectes sapidus 1.87310 0.07117 (NS)

Overall faunal abundance between sites 5.92468 1.9588 (NS)

Note. NS = not significant. Data was log transformed, significant if α ≤ 0.05, listed in descending order of significance. ***

**

*

***

Figure 6. The total abundance of dominant fish species recovered at the sampling locations over the entire course of the study.

* ≤ 0.05, ** ≤ 0.01, *** ≤ 0.001 Figure 7. Difference in total abundance of all species in Site 1 as a percentage difference from total abundance at Site 2 L. xanthurus (Spot) showed particular variability presumably related to spawning

(Figure 8). These fish were either nonexistent or in very low numbers from May through

December 2002, but increased after the beginning of the year. In January, young of the year began appearing and were present through the spring, although the population dropped again in April at both sites and by June, none were captured in Site 2. However, low numbers of spot were captured in Site 1 through the end of sampling in August.

Except for large numbers of fish captured in Site 2 in February 2003, this species was more consistently present and significantly more abundant at Site 1 throughout the sampling period, although patterns of abundance were highly correlated between sites

(correlation coefficent = 0.81).

M. cephalus (Striped mullet) were found in large numbers in both sampling areas, starting in January 2003 (Figure 9). Abundance of this species in Site 1 increased from zero in December 2002 to over 600 in early January 2003. Individual numbers peaked in

March, with over 3,000 juveniles caught, but declined in later spring and summer months.

Abundance in Site 2 was almost completely attributable to fish collected during a single date in March 2003. Besides this peak, less than ten individual mullet were captured during any sampling event in Site 2, and overall abundance of this species was significantly greater at Site 1 compared with Site 2 (Table 6).

43 3000 4500 2500 Site 1 Total 4000 Site 1 Total 2000 Site 2 Total 3500 Site 2 Total 3000 1500 2500 2000 1000 1500 500 1000 500 0 0 2 2 2 2 2 3 3 3 3 2 2 2 2 2 2 3 3 3 3 02 ­500 0 ­500 00 00 00 0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 7/ 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 1 / 7/ 0/ 1/ 0/ 2/ 5/ 9/ 7/ 9/ 7/ 7/ 0/ 1/ 0/ 2/ 5/ 7/ 9/ 9 5/ / / / / 2 1 2 1 2 2 2 1 2 1 2 1 2 2 2 * / / / / 2 / 3 / / / / / / / 2 / / / 3 6 8 9 1 1 4 6 6 8 9 1 1 4 6 11 *5 11

Figure 8. Leiostomus xanthurus (Spot) abundance comparison. Figure 9. Mugil cephalus (Striped mullet) abundance comparison.

Error bars denote standard error. Error bars denote standard error.

700 Site 1 Total 120 600 Site 2 Total 100 500 Site 1 Total 80 400 Site 2 Total 300 60 200 40 100 20 0 0 2 2 2 2 2 2 3 3 3 3 3 02 02 02 02 02 02 03 03 03 03 ­100 ­20 0 0 0 0 0 0 0 0 0 0 0 7/ 3/ 0/ 1/ 9/ 0/ 1/ 2/ 2/ 4/ 9/ /2/ /9/ 1 2 1 2 1 3 1 2 1 1 1 17/ 27/ 10/ 21/ 10/ 25/ 27/ 29/ / / / / / / / / / / / 3 6 8 9 1 2 4 6 7 5/ 6/ 8/ 9/ 1/ 12 1/ 4/ 6/ *5 10 11 * 1

Figure 10. Menidia peninsulae (Silverside) abundance comparison. Figure 11. Lagodon rhomboides (Pinfish) abundance comparison.

Error bars denote standard error. Error bars denote standard error. M. peninsulae (Tidewater silverside) was one of the few species found in greater numbers within open water at Site 2 (Figure 10). Very few fish were found in Site 1 or

Site 2 until mid­October, when fish were captured with regularity. Peak numbers appeared in January. While the highest individual catches were in Site 1, sampling results showed similar populations in both sites but an overall significant preference for Site 2

(Table 6; p = 0.026). A total of 1,949 silversides were caught in Site 2, while Site 1 had

1,534.

L. rhomboides (Pinfish) abundance never reached the same numbers as the preceding species in any individual sampling effort yet had the second most significant difference of any species analyzed in the study (Table 6). The overall catch of 522 individuals in Site 1 was significantly greater than the 113 caught in Site 2 (Figure 13).

The presence of this species was relatively consistent throughout the year, although their incidence in Site 2 negatively correlated (correlation coefficient = ­0.28) with that of L. xanthurus (Spot). Pinfish were not found during the winter (November through January) but were recovered again in March.

C. sapidus (Blue crab) was the only crustacean present in numbers large enough to analyze (Figure 12). Fewer than ten crabs were captured per sampling effort until

January 2003, when more than a dozen small juvenile (0.5­2.0 cm) crabs were captured at a time in Site 1. Total numbers captured were greater at Site 1 but results from paired t test show sites were not significantly different (α > 0.05), although the p value was under

0.10 (Table 6). Overall numbers decreased by June.

45 25

20

Site 1 Site 2

15

10

5

0

2 2 2 2 2 2 2 2 2 2 2 2 2 3 3 3 3 3 3 3 0 /02 0 0 /0 /0 /0 /0 /0 0 /0 /02 /02 /0 /0 /03 /03 /03 /0 /03 /03 /0 /0 0 0 /03 /03 2 7 3 0 0 7 9 0 4 0 4 1 5 6 3 2 7 6 9 / / / 1 2 / /7/0 1 /1 /2 /3 /2/0 / /1 /9/0 /11 / /17/ 6 /15/ /27/ 7 8 / / 9 /21/ 0 / 1 1 1 2 1 1 /2 /1 /22 3 /2 /1 /2 5 /14/ /29/ 7 /1 *5 6 6 8 8 9 1 10 1 1 1 1 1 2 2 3 4 4 6 6 7

­5 Dates

Figure 12. Callinectes sapidus (Blue crab) abundance comparison The remaining 30 species totaled less than 5% of the overall abundance, with no other individual species accounting for more than 1.16% of the overall catch. The infrequently occurring species are listed by rank abundance order and site (Tables 7 & 8).

Several C. variegatus, a typical marsh resident species, occurred in Site 1 but were not found at Site 2. Four additional species occurring in Site 1, but not Site 2, were

Hyporhampus unifasciatus (Halfbeak), Opsanus beta (Gulf toadfish), Caranx spp. (Jack), and Sciaenops ocellatus (Red drum). Two species, Arius felis (Hardhead catfish) and

Archosargus probatocephalus (Sheepshead), were found in Site 2 but not Site 1.

Comparative abundance for all of the infrequently occurring species is shown in Figure

13.

Highly significant differences were found between site abundances for

Eucinostomus argenteus (Spotfin mojarra), P. pugio (Grass shrimp), and F. similis

(Longnose killifish) numbers while there were not any significant differences between the Oligoplites saurus (Leatherjacket) sample numbers (Table 9). All four of these species occurred more frequently at Site 1 (Figure 14).

Of the 35 species caught, at least seven are of commercial value, including M. cephalus (Striped mullet), C. sapidus (Blue crab), and two Paralichthys (Flounder) species. A single juvenile Sciaenops ocellatus (Red drum) was caught by seine. Important baitfish and crustaceans were present at both sites, including F. similis, L. rhomboides, and P. pugio.

47 Table 7. Rank Order for Infrequently Occurring Species at Site 1

Site 1 Total Site 1

Rank Order Species individuals % of total

1 Eucinostomus argenteus 166 1.16

2 Fundulus similis 114 0.80

3 Callinectes sapidus 104 0.73

4 Palaemonetes pugio 62 0.43

5 Oligoplites saurus 49 0.34

6 Synodus foetens 36 0.25

7 Cyprinidon variegatus 25 0.18

8 Elops saurus 17 0.12

9 Chilomycterus schoepfi 14 0.10

9 Harengula jaguana 14 0.10

9 Paralichthys albigutta 14 0.10

10 Pagurus berhardus 13 0.09

10 Strongylura marina 13 0.09

11 Symphurus minor 10 0.07

11 Trachurus lathami 10 0.07

11 Trachinotus carolinus 10 0.07

12 Orthopristis chrysoptera 9 0.06

13 Prionotus tribulus 7 0.05

14 Syngnathus leptorhynchus 4 0.03 Table 7 (continued). Rank Order for Infrequently Occurring Species at Site 1

Site 1 Total Site 1

Rank Order Species individuals % of total

15 Hyporhamphus unifasciatus 3 0.02

15 Littorina irrorata 3 0.02

15 Paralichthys lethostigma 3 0.02

16 Citharichthys macrops 2 0.01

16 Gobiesox strumosus 2 0.01

17 Caranx spp. 1 0.01

17 Fundulus grandis 1 0.01

17 Menticirrhus americanus 1 0.01

17 Opsanus beta 1 0.01

17 Sciaenops ocellatus 1 0.01

18 Archosargus probatocephalus 0 0.00

18 Arius felis 0 0.00

Total 709 4.97 Table 8. Rank Order for Infrequently Occurring Species at Site 2

Site 2 Site 2

Rank Order Species Total individuals % of total

1 Littorina irrorata 97 0.96

2 Callinectes sapidus 46 0.45

3 Oligoplites saurus 43 0.42

4 Eucinostomus argenteus 42 0.41

5 Trachinotus carolinus 16 0.16

5 Trachurus lathami 16 0.16

6 Strongylura marina 15 0.15

7 Arius felis 14 0.14

8 Prionotus tribulus 11 0.11

9 Palaemonetes pugio 10 0.10

10 Pagurus berhardus 9 0.09

11 Syngnathus leptorhynchus 8 0.08

12 Fundulus similis 7 0.07

12 Paralichthys albigutta 7 0.07

12 Synodus foetens 7 0.07

13 Harengula jaguana 5 0.05

13 Menticirrhus americanus 5 0.05

13 Symphurus minor 5 0.05 Table 8 (continued). Rank Order for Infrequently Occurring Species at Site 2

Site 2 Site 2

Rank Order Species Total individuals % of total

14 Chilomycterus schoepfi 4 0.04

14 Paralichthys lethostigma 4 0.04

15 Archosargus probatocephalus 1 0.01

15 Elops saurus 1 0.01

15 Citharichthys macrops 1 0.01

15 Gobiesox strumosus 1 0.01

15 Orthopristis chrysoptera 1 0.01

16 Caranx spp. 0 0.00

16 Cyprinidon variegatus 0 0.00

16 Fundulus grandis 0 0.00

16 Hyporhamphus unifasciatus 0 0.00

16 Opsanus beta 0 0.00

16 Sciaenops ocellatus 0 0.00

Total 376 3.72 Fi gur Total abundance e 13. 1 1 1 1 8 1 6 4 2 0 0

0 8 0 6 0 4 C 0 2 0 0 0 0 0 o m parat Archosargus probatocephalus Sp i v ecies e a Callinectes sapidus b u

n Chilomycterus schoepfi da n ce Cyprinidon variegatus f o r

a Eucinostomus argenteus l l i n f r Fundulus similis eque

n Harengula jaguana t l y o cc Littorina irrorata ur r i n Oligoplites saurus g s pec Orthopristis chyrsoptera i e s Palaemonetes pugio

Paralichthys lethostigma

Sciaenops ocellatus

Sygnanthus leptorhynchus Site Site 2 1

Synodus foetens

Trachurus lathami 180 *

160

140 *** Site 1

120 e Site 2 c n a

d 100 n u b 80 *** tal a NS To 60

40

20

0 Eucinostomus Fundulus similis Oligoplites saurus Palaemonetes argenteus pugio Species

Figure 14. Comparison of abundance for four infrequently occurring species. * ≤ 0.05, ** ≤ 0.01, *** ≤ 0.001, NS = not significant Table 9. Comparison of Four Infrequently Occurring Species Between the Sampling Sites by Paired Two­Sample t Test For Means

Species t Statistic P (T<=t) two­tailed

Fundulus similis 4.3214 0.000212

Palaemonetes pugio 4.2347 0.000212

Eucinostomus argenteus 2.5507 0.016290

Oligoplites saurus 0.1275 0.899340

Note. Data was log transformed, significant if α < 0.05, listed in descending order of significance. Community Structure

A highly significant difference (p < 0.001) in the community structure of sampled fauna from Site 1 and Site 2 over time was found by a 2­way crossed analysis of similarity (ANOSIM) using PRIMER­E software (Figure 15). Results of the ANOSIM based on the species present and sampling dates and locations showed that the replicates within each site were more similar to each other than replicates from different sites, thereby forming two different community structures between Site 1 and Site 2.

Figure 15. 2­D Multi­dimensional scaling plot representing analysis of similarity between

Site 1 and Site 2 community structure. Site 1 = circles, Site 2 = triangles.

55 A SIMPER (similarity percentages) analysis assumes there are no differences between the two sites (100% similar), and therefore, a measure of dissimilarity shows how the two sites are different. The SIMPER results show to what degree the sites are different and in this study L. xanthurus (Spot), M. cephalus (Striped mullet), and M. peninsulae

(Tidewater silverside) account for the most variability between the two sites. The average dissimilarity overall between the two habitats is 78.92, with an average of 15.9 from M. peninsulae and 15.3 from L. xanthurus, and each species accounting for approximately,

20% of the dissimilarity between the two groups. The analysis assumes there are no differences between the two sites. Just five species of the 35 found contribute two­thirds of the dissimilarity between the two habitats (Table 10).

56 Table 10. Average Dissimilarity Between Habitats

Site 1 Site 2

Fig. Scientific Average Average Average Dissimilarity Contributing % Cumulative % name abundance abundance Dissimilarity

10 M. peninsulae 35.90 32.48 15.96 1.13 20.22 20.22

8 L. xanthurus 91.40 61.45 15.31 0.83 19.40 39.61

9 M. cephalus 100.28 66.78 10.95 0.67 13.88 53.49

11 L. rhomboides 8.67 1.90 7.19 1.04 9.11 62.60

14 E. argenteus 2.68 0.70 4.13 .64 5.23 67.84

12 C. sapidus 1.78 0.75 3.33 0.87 4.23 72.06

14 F. similis 1.93 0.03 3.19 0.55 4.04 76.11

Between sites 78.92 Species Richness

In 28 of 30 sampling events taken during the span of the study, Site 1 had greater species richness. For the majority of the samples, Site 1 had two to five more taxa (out of

35 total) per haul than Site 2 (Figure 16). Up to 12 different species were found at once during a single sampling event in Site 1, but the most species for a single seine haul at

Site 2 was eight. Species richness demonstrated an upward trend over time in both sampling locations, but more noticeably in Site 1. Species associated with hard reef such as O. beta and Chilomycterus scoepfi (Striped burrfish) along with seagrass­associated species like Syngnathus leptorhynchus (Bay pipefish) and L. rhomboides (Pinfish) were found predominantly in Site 1. Using a paired t test for repeated measures, however, showed that there was no overall significant difference in the species richness between the two sites, with p values > 0.05. The lack of statistical significance may be due to the fact that overall numbers of species were low in both Site 1 and Site 2.

Species richness (d) was consistently higher at Site 1 (Table 11). On average the

Shannon diversity in Site 1 was nearly identical to Site 2. Simpson diversity and Pielou’s evenness were slightly greater at Site 2.

58 Table 11. Species Richness and Diversity

Simpson

Total Species Pielou's Shannon diversity

Individuals richness evenness diversity (1­

Species (N) (d) (J') (H' log e) lambda)

H1S1 31 9051 3.2929 0.34211 1.1748 0.5675

H1S2 27 5205 3.0383 0.41439 1.3658 0.6114

H1 Average 29 7128 3.1656 0.37825 1.2703 0.5894

H2S1 25 6073 2.7549 0.3799 1.2229 0.6320

H2S2 23 4058 2.6481 0.41157 1.2905 0.6343

H2 Average 24 5066 2.7015 0.39573 1.2567 0.6332

Note. Determined by the PRIMER biodiversity analysis DIVERSE.

H1 = Habitat 1/Site 1, H2 = Habitat 2/Site 2, S = sample followed by number 12

Site 1 mean

10 Site 2 mean

8

6

4

2

Figure 16. Species richness comparison using mean number of species captured during repeated hauls. Error bars denote standard error. Size

Because the majority of juvenile fish were caught between the winter spawning peak times during January­April 2003, these fish were examined more closely to ascertain whether any particular patterns could be noted in size. The four most common fish were divided into size classes by measuring total length (TL) and broken into three classes (Class 1: 0­4.5 cm; Class 2: 5­9.5 cm; Class 3: 10­20 cm) to compare sizes between sites.

Leiostomus xanthurus (Spot).

Spot were first collected on January 10, 2003. The largest numbers of Class 1 fish were captured in mid February through March in both sites (Figure 17). By April, spot were rarely caught. For fish in Class 1 at Site 1, at least six sampling events yielded more than 500 fish and three events had over 100, while in Site 2 only one event had over 500 fish. This sampling event, however, was a peak of 2500 fish in one haul. Three samples had over 200 fish, and the overall peaks in population for spot were in February and March 2003. A paired t test did not show any significant differences between sites for fish in Class 1 (Table 12).

61 Table 12. Comparison of Total L. xanthurus (Spot) by Size Class Between the Sampling

Sites by Paired Two Sample t Test for Means

Class t Statistic P (T<=t) two­tailed

1 2.093469 0.069641 (NS)

2 ­0.133097 0.897431 (NS)

3 0.5568979 0.5911744 (NS)

Note. Data was log transformed, significant if α < 0.05. NS = not significant.

For Class 2, no fish were recovered until February 15 and only five hauls in Site

1 yielded fish, each haul having 25 or fewer individuals (Figure 18). Most hauls in Site 2 had 25 or fewer individuals, except for a peak of 225 fish in February. For the largest size class, less than ten fish were found at any given site or time, and those caught were in February (Figure 19). Fifteen fish were caught during two hauls in late February, and negligible numbers found in either site through March. There were not any significant differences in site preferences for fish in Classes 2 and 3 (Table 13).

62 2000 140 Site 1 Mean Site 1 Mean 1500 120 Site 2 Mean 100 Site 2 Mean 1000 80 60 500 40 20 0

0 3 3 3 3 3 3 3 3 3 0 0 0 0 0 0 0 0 0 03 03 03 03 03 03 03 03 ­20 03 0 0 0 0 0 0 0 0 0

­500 0 0 0 0 0 0 0 0 0 2 2 2 2 2 2 2 2 2 / / / / / / / / / /2 /2 /2 /2 /2 /2 /2 /2 /2 3 7 1 4 8 4 8 1 5 / 7 1 4 8 4 8 1 5 3 1 3 1 2 1 2 1 2 1 / / / / / / / / 1/ /1 /3 /1 /2 /1 /2 /1 /2 1 1 2 2 3 3 4 4 1 1 2 2 3 3 4 4

Figure 17. L. xanthurus abundance for Class 1 (0­4.5 cm). Figure 18. L. xanthurus abundance for Class 2 (4.5­9.5 cm).

Error bars represent standard error. Error bars represent standard error. 9 8 7 Site 1 Mean 6 Site 2 Mean 5 4 3 2 1 0 ­1 2003 2003 2003 2003 ­2 2003 3/ 24/ 21/ 22/ 26/ 1/ 1/ 2/ 3/ 4/ Figure 19. L. xanthurus abundance in Class 3 (9.5­20 cm). Error bars represent standard error. Mugil cephalus (Striped mullet).

The majority of striped mullet were found in Site 1, although Class 1 fish peaked at both sites on March 22, 2003, when an average of 2000 young­of­the­year were counted in each sampling location. Very few of this size were found after early April

(Fig. 20). A paired t test showed significantly higher numbers recovered at Site 1 for fish in Class 1 (Table 13).

Table 13. Comparison of Total M. cephalus (Striped Mullet) by Size Class Between the

Sampling Sites by Paired Two Sample t Test for Means

Class t Statistic P (T<=t) two­tailed

1 2.395685946 0.043468391*

2 1.700262958 0.12750211 (NS)

3 0.695381367 0.504373485 (NS)

Note. NS = not significant,* ≤ 0.05, data was log transformed, significant if α < 0.05

Mullet in Class 2 were found predominantly in Site 1 only, with only two fish captured in Site 2 (Figure 21). No more than two fish were ever caught per sampling effort in Class 3 or higher (Figure 22), most likely due to the larger fishes’ swimming speed and ability to jump. However, we observed dozens of larger mullet jumping within both sample areas. There were not any significant differences found between sites for fish in Class 2 and 3 (Table 13).

64 2500 80 Site 1 M ean 70 2000 Site 1 M ean Site 2 M ean 60 1500 50 Site 2 M ean 1000 40 30 500 20 10 0 0 3 3 3 3 3 3 3 3 3

­500 0 0 0 0 0 0 0 0 0 ­10 0 03 03 03 03 03 03 03 03 03

/20 /20 /20 /20 /20 /20 /20 /20 ­20 20 20 20 20 20 20 20 20 20 /3/2 3/ 7/ 1/ 4/ 8/ 4/ 8/ 1/ 5/ 1 /17 /31 /14 /28 /14 /28 /11 /25 1 1 2 2 3 3 4 4 1/ /1 /3 /1 /2 /1 /2 /1 /2 1 1 2 2 3 3 4 4

Figure 20. M. cephalus abundance for Class 1 (0­4.5 cm). Figure 21. M. cephalus abundance for Class 2 (4.5­9.5 cm).

Error bars represent standard error. Error bars represent standard error. 1.2 1 Site 1 M ean Site 2 M ean 0.8 0.6 0.4 0.2 0 3

­0.2 03 03 03 03 200 20 20 20 20 3/ 4/ 1/ 2/ 6/ 2 2 2 2 1/ / / / / 1 2 3 4

Figure 22. M. cephalus abundance for Class 3 (9.5­20 cm).

Error bars represent standard error. Lagodon rhomboides (Pinfish).

Juvenile pinfish began to be captured after March (Figure 23). Fish in the smallest size category did not show any significant differences (Table 14). The population peaked in April but showed a downward trend to almost zero in later sampling events. By comparison, Class 2 fish were numerous in Site 1 (Figure 24), and showed highly significant differences (Table 15). A steady rise occurred among fish in this class from late April through the summer, with a drop in late June but a peak two weeks later in July. The Class 1 population of juvenile pinfish in Site 1 decreased from in April concomitant with an increase in Class 2 fish after late April and through the summer.

Table 14. Comparison of Total L. rhomboides (Pinfish) by Size Class Between the

Sampling Sites by Paired Two Sample t Test for Means

Class t Statistic P (T<=t) two­tailed

1 2.156237558 0.067984575 (NS)

2 3.007496176 0.019731848*

3 0.127756418 0.901934499 (NS)

Note. NS = not significant, * ≤ 0.05, data was log transformed, significant if α < 0.05

Fewer than five fish from Class 3 were ever captured in either site, and no significant differences were noted (Figure 25). Members of the species were found predominantly at

Site 1, so little can be noted about the size distributions at Site 2 except for a slight increase through the summer for fish in Class 2. 66 25 60 Site 1 Mean 20 50 Site 1 Mean Site 2 Mean 40 Site 2 Mean 15 30 10 20 5 10 0 0

3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3

0 0 0 0 0 0 0 0 0 ­10

­5 0 0 0 0 0 0 0 0 0 200 200 200 200 200 200 200 200 200 2 2 2 2 2 2 2 2 2 / / / / / / / / / / / / / / / / / / 6 4 1 6 4 1 3 0 8 5 9 3 / / / / / / 2 2 1 1 2 1 23 20 18 15 29 13 / 4 / 5 / 6 / / / 4 5 6 3 4 5 6 6 7 3/ 4/ 5/ 6/ 6/ 7/

Figure 23. L. rhomboides abundance for Class 1 (0­4.5 cm). Figure 24. L. rhomboides abundance for Class 2 (4.5­9.5 cm).

Error bars represent standard error. Error bars represent standard error.

5 Site 1 Mean 4 Site 2 Mean 3 2 1 0

3 3 3 3 3 3 3 3 3 0 0 0 0 0 0 0 0 0

­1 0 0 0 0 0 0 0 0 0 2 2 2 2 2 2 2 2 2 / / / / / / / / / 6 4 1 3 0 8 5 9 3 / / / 2 2 1 1 2 1 / 4 / 5 / 6 / / / 3 4 5 6 6 7

Figure 25. L. rhomboides abundance for Class 3 (9.5­14.5 cm). Error bars represent standard error. Menidia peninsulae (Tidewater silverside).

The smallest tidewater silversides, Class 1, were present in January 2003 within both habitats, but no more of these fish were found in Site 2 until April, when a single fish was captured. Very few members of the species were found at Site 1 until April, when numbers were recovered to levels similar to January (Figure 26). For Class 2, these fish were found in larger numbers consistently through February, March, and April

(Figure 27). The majority of fish captured were in Class 2, with peak numbers in January.

Analysis by paired t test showed there was not any significant difference found between fish sizes at Sites 1 and 2 for Classes 1 or 2 (Table 15).

Table 15. Comparison of Total M. Peninsulae (Tidewater Silverside) by Size Class

Between the Sampling Sites by Paired Two Sample t Test for Means

Class t Statistic P (T<=t) two­tailed

1 1.14663046 0.284669987 (NS)

2 ­0.799510211 0.447081309 (NS)

3 ­2.728585736 0.025902394*

Note. NS = not significant, * ≤ 0.05, data was log transformed, significant if α < 0.05

For Class 3, less than ten fish were found in Site 1 between February and April, while relatively large numbers were found in the Site 2 (Figure 28). Overall, presence in Site 1 was recorded in late February and peaked in April, while a consistent presence and variety of sizes were captured at Site 2. The average number of silversides found in Site

68 1 was less than 100, while Site 2 held more than 100 on average. A paired t test showed a highly significant difference between sites for Class 3 fish (Table 15).

69 100 250 80 Site 1 Mean Site 1 Mean Site 2 Mean 200 Site 2 Mean 60 150 40 100 20 50 0 0 3 3 3 3 3 3 3 3 3 03 ­50 03 03 03 03 03 03 03 03 00 00 00 00 00 00 00 00 ­20 00 20 20 20 20 20 20 20 20 20 2 /3/ 7/2 1/2 4/2 8/2 4/2 8/2 1/2 5/2 17/ 31/ 14/ 28/ 14/ 28/ 11/ 25/ /3/ 1 1 1/ 1/ 2/ 2/ 3/ 3/ 4/ 4/ 1/1 1/3 2/1 2/2 3/1 3/2 4/1 4/2 Figure 26. M. peninsulae abundance for Class 1 (0­4.5 cm). Figure 27. M. peninsulae abundance for Class 2 (4.5­9.5 cm).

Error bars denote standard error. Error bars denote standard error.

80 70 Site 1 Mean 60 Site 2 Mean 50 40 30 20 10 0

­10 3 3 3 3 3 3 3 3 3 0 0 0 0 0 0 0 0 0

­20 0 0 0 0 0 0 0 0 0 /2 /2 /2 /2 /2 /2 /2 /2 /2 7 1 4 8 4 8 1 5 /3 1 /1 /3 /1 /2 /1 /2 /1 /2 1 1 2 2 3 3 4 4

Figure 28. M. peninsulae abundance for Class 3 (9.5­14.5 cm). Error bars represent standard error. DEP Sampling Results

In February, May, and August 2005 the FDEP Ecosystem Restoration

Department responsible for Project GreenShores conducted fish sampling to monitor postcreation effects of the new marsh and reef. The same seine was used but methodology differed in that four hauls were conducted per site instead of two and no size data was collected. Similar species were captured in the DEP study and abundance patterns were consistent with the findings from 2002­2003 (Figures 29, 30, 31, 32).

Sampling on August 25, 2005 was conducted after Hurricane Katrina, and no samples were taken from Site 2 due to excessive debris in the water. For comparison purposes, repeated measures tests were run on the overall abundance of the same four species dominating the 2002­2003 sampling. No significant differences were noted between

Sites 1 and 2 for overall abundance (p = 0.377) nor for abundance of M. peninsulae (p =

0.576), L. rhomboides (p = 0.607), M. cephalus (p = 0.284), and L. xanthurus (p = 0.355).

Overall, 5,481 individual fish were captured, with 4,390 in Site 1 and 1,091 in

Site 2. Thirty species were represented, with 28 at Site 1 but just 11 at Site 2 (Table 16).

Total numbers of individuals for 26 species were higher at Site 1, while Micropogonias undulatus (Atlantic croaker) and M. peninsulae (Tidewater silverside) dominated the

Site 2 catch and outnumbered those in Site 1. While the total species count was similar,

17 species were not previously documented in the 2002­2003 sampling. These included commercially important species Cynoscion nebulosus (Speckled trout), Lutjanus synagris (Lane snapper), and Lutjanus griseus (Mangrove snapper). A single cow nose ray (Rhinoptera bonasus) was also collected.

71 Table 16. Species Collected During DEP Sampling (February­August 2005), Abundance and Percentage of Total Designated by Site

Site 1 Site 2 Site 2 Species Site 1 Total % Total % Total Total abundance abundance

Lagodon rhomboides 2025 46.13 189 17.32

Bairdiella chrysoura* 751 17.11 0 0.00

Mugil cephalus 550 12.53 4 0.37

Leiostomus xanthurus 253 5.76 133 12.19

Micropogonias undulatus* 214 4.87 391 35.84

Menidia peninsulae 159 3.62 308 28.23

Mugil curema* 156 3.55 0 0.00

Harengula jaguana 72 1.64 0 0.00

Eucinostomus argenteus 53 1.21 25 2.29

Fundulus grandis 36 0.82 0 0.00

Arenigobius bifrenatus* 32 0.73 6 0.55

Anchoa mitchilli* 21 0.48 20 1.83

Orthopristis chrysoptera 17 0.39 0 0.00

Sphyraena barracuda* 9 0.21 0 0.00

Opsanus beta 8 0.18 0 0.00

Brevoortia patronus 8 0.18 0 0.00 Table 16 (continued). Species Collected During DEP Sampling (February­August 2005),

Abundance and Percentage of Total Designated by Site

Site 1 Site 2 Site 2 Species Site 1 Total % Total % Total Total abundance abundance

Cynoscion nebulosus* 5 0.11 0 0.00

Penaeus aztecus* 4 0.09 0 0.00

Lutjanus synagris* 3 0.07 0 0.00

Sciaenops ocellatus 2 0.05 0 0.00

Eleotris pisonis* 2 0.05 1 0.09

Cyprinidon variegatus 1 0.02 0 0.00

Lagocephalus laevigatus* 1 0.02 0 0.00

Symphurus spp. 1 0.02 0 0.00

Pomatomus saltatrix* 1 0.02 0 0.00

Lutjanus griseus* 1 0.02 0 0.00

Rhinoptera bonasus* 1 0.02 0 0.00

Penaeus spp.* 0 0.00 13 1.19

Urophycis floridana* 0 0.00 1 0.09

Total 4390 100 1091 100

Note. * Not recorded in 2002­2003 data. Figure 29. Comparison of species abundances from DEP sampling in 2005; species selected for comparison to 2002­2003 study. 2000

Site 1 Site 2

1500

1000

500

0 Feb­05 Mar­05 Apr­05 May­05 Jun­05 Jul­05 Aug­05

­500 Dates

Figure 30. Total abundance comparison by date for L. rhomboides (Pinfish) in DEP sampling. Error bars denote standard error. 300

250 Site 1 Site 2 200

150

100

50

0 Feb­05 Mar­05 Apr­05 May­05 Jun­05 Jul­05 Aug­05

­50

­100 Dates

Figure 31. Total abundance comparison by date for L.xanthurus (Spot) in DEP sampling. Error bars denote standard error. 500

400 Site 1 Site 2 300

200

100

0 Feb­05 Mar­05 Apr­05 May­05 Jun­05 Jul­05 Aug­05

­100

­200 Dates

Figure 32. Total abundance comparison by date for M. peninsulae (Tidewater silverside) in DEP sampling. Error bars denote standard error. Table 17. Summary Table of Statistical Analyses for Four Dominant Species

Mullet Spot Silverside Pinfish Total

Site 1 Site 2 Site 1 Site 2 Site 1 Site 2 Site 1 Site 2 Site 1 Site 2

Total Abundance 6017 4006 5483 3687 1528 1949 519 113 14256 10131

Abundance (p values) 0.00042* 0.00386* 0.02556* 0.00062* 1.9588

Average abundance 100.28 66.78 91.40 61.45 35.90 32.48 8.67 1.90  

Average dissimilarity 10.95 15.31 15.96 7.19 78.92

Size (Class 1 p value) 0.0435* 0.0696 0.2847 0.0680 

Size (Class 2 p value) 0.1275 0.8974 0.4471 0.0197* 

Size (Class 3 p value) 0.5044 0.5912 0.0260* 0.9019 

Avg. species richness         3.1656 2.7015

Avg. Shannon Diversity         1.2703 1.2567

Avg. Simpson diversity         0.5894 0.6332

Note. Values repeated for each site if comparison was between sites, asterisk * if p value is significant (α ≤ 0.05) for location CHAPTER V

DISCUSSION

This thesis evaluated the importance of habitat complexity for recruitment and species diversity of mobile estuarine fauna. The study encompasses a time course of habitat change in one of two similar and adjacent shallow sandy bottom sites. The habitat change involved placement of a rock reef and creation of intertidal areas planted with S. alterniflora. Thus, the study provides both a comparison of habitat type and habitat change over time in addressing the importance of structural complexity and habitat diversity. With a few exceptions, the addition of habitat complexity and proximity to newly planted vegetation had consistently enhanced fish and blue crab populations over the temporal variance observed.

Manmade structures such as artificial reefs have been used since the 17 th century

(Hiroshi, 1998) to create habitat for fish because they provide refuge and substrate for vegetative food sources (Pickering & Whitmarsh, 1996). Many recent habitat creation projects have shown that fauna will utilize and respond positively to these sites, often within 1­2 years of construction (Chabreck, 1990; Jenkins & Sutherland, 1997; Meyer &

Townsend, 2000). Results from the study of open bottom adjacent to the created oyster reef and marsh within Project GreenShores suggest this site functioned similarly.

Overall abundance at both Sites 1 and 2 increased significantly from May and June 2002

79 to May and June 2003. This temporal change may represent natural interannual variation or an overall improvement for the larger shoreline habitat with the addition of

GreenShores. Interannual variation could be explained by EPA research in Pensacola

Bay (Murrell, 2003), which showed a strong interannual fluctuation of bacterioplankton related to freshwater input in the bay, which could in turn affect the amount of oxygen available for nekton. Allen and Barker (1990) also demonstrated similar effects on larval fish abundances due to low salinity periods. However, an overall improvement may have occurred as other research has shown that larger reefs (> 4000 cubic meters) tend to produce fish, as do those situated within a sandy, structure­free bottom (Borntrager &

Farrell, 1992; Bohnsack et al., 1994). The creation site monitored within this thesis fits both of those criteria. In addition, trends in abundance within both sites increased noticeably in early 2003, coinciding with both the end of site construction and entrance of young­of­the­year into the estuary. These findings show potential exists for enhanced fisheries attraction and production on a regional scale encompassing both the intertidal control and treatment sites.

Most studies of faunal abundance in estuarine ecosystems fall into two categories: comparison of a structurally complex habitat to one of lesser complexity or comparison of restored/created habitats (usually salt marshes) to existing ones (Jenkins & Wheatley,

1998; Rozas & Minello, 1998; Minello & Zimmerman, 1992). Structure within these studies includes artificial reef, oyster reef, seagrasses, freshwater and saltwater marshes, and many combinations thereof. The majority of these studies show positive responses— increased species diversity and greater abundance—in the sites containing structure when compared to open bottom (Jenkins & Sutherland, 1997; Peterson et al., 2000;

80 Rozas & Zimmerman, 2000). Research has shown that created oyster reefs are colonized in a short time (Meyer & Townsend, 2000; Piazza et al., 2005) and restored salt marshes generally share characteristics of comparable, naturally occurring marshes

(Talley & Levin, 1999; Jivoff & Able, 2003; Able et al., 2004). The research in

Pensacola Bay took a different approach from these studies by comparing two open water habitats and observing differences over time.

While fish commonly utilize complex habitats, open bottom is also an important habitat for some species. In addition to foraging areas, sandy bottom has been shown to be a “staging area” for juveniles before migration (Minello et al., 1987). Several species within this study—M. peninsulae (Tidewater silverside), L. xanthurus (Spot), and

Symphurus minor (Largescale tonguefish) for example—prefer it for foraging or camouflage. Two of the most prevalent species, M. cephalus (Striped mullet) and L. xanthurus (Spot), are also typical residents of open bottom (Rozas & Zimmerman, 2000).

While the proximity of structural complexity did not appear to enhance M. peninsulae

(Tidewater silverside) numbers, two other open water species, M. cephalus (Striped mullet) and L. xanthurus (Spot), were recovered in significantly higher numbers at the habitat creation site, even at this early stage of construction.

The formation of two significantly different communities within open bottom over a relatively short period is one of the more notable findings within this study. The fish assemblages were similar for each site, and statistical analysis showed that the primary differences in communities lay in the abundances of just three species: L. xanthurus (Spot), M. cephalus (Striped mullet), and M. peninsulae (Tidewater silverside).

These taxa accounted for over 90% of the total abundance in each site. Previous research

81 has also shown that differences in community structure and overall abundance can be attributable to a small number of species (Jenkins & Sutherland, 1997; Peterson et al.,

2000). While repeated measures tests comparing overall abundance at both sites did not show any significant differences, analysis of the three most frequently occurring species, and several of the infrequently occurring ones, did show a difference in populations between Site 1 and Site 2.

Juvenile density in a specific area is an important characteristic of habitat value

(Minello et al., 2003). These young fish may better reflect any site differences due to adults’ greater mobility, territoriality, and removal by fishing (Rozas & Minello, 1997) and may reflect recruitment trends. Certainly the capture method used in this work was biased towards juveniles. Abundance in both sites coincided with spawning peaks

(January­March), when thousands of young­of­the­year, especially L. xanthurus (Spot) and M. cephalus (Striped mullet) were schooling (Florida Fish & Wildlife Conservation

Commission [FFWCC], 2005b; Hill, 2005). The highly correlated nature of the data in both sites is most likely due to the seasonality and population dynamics of the organisms in the larger bay system. However, within these seasonal and life history trends, the consistently higher and significantly different overall density of key species in Site 1 suggests the improved habitat facilitated recruitment.

With the exception of M. peninsulae (Tidewater silverside), which demonstrated a strong preference for open bottom in sampling efforts in 2002­2003 and 2005, most specimens were recovered in greater numbers in the vicinity to marsh edge and reef.

Other literature (Rozas & Minello, 1998; Rozas & Zimmerman, 2000) suggests silversides prefer open water, and our study does not refute that finding. The highly

82 significant difference in presence of L. rhomboides (Pinfish), a species commonly found over grassbeds, marshes, and manmade structures such as piers and pilings (Hoese &

Moore, 1977; Irlandi & Crawford, 1997), at Site 1 indicated fish were differentiating between the two locations. Young M. cephalus (Striped mullet) were more abundant at

Site 1, which could be attributed to their preference for vegetative matter (Odum, 1968).

P. pugio and F. similis, species well documented to prefer salt marshes (Connolly, 1999;

Oviatt & Raposa, 2000; Teal & Weinstein, 2002), were found in significantly greater abundance in Site 1. Juvenile L. xanthurus (Spot) are grazers of benthic sediments

(Phillips, Huish, Kerby, & Moran, 1989) and are typically found over sandy and muddy bottoms (Hill, 2005) so their presence was expected in both sites.

The most commonly found crustacean within the study was C. sapidus (Blue crab). Although more individuals may have been captured if some of the sampling had taken place at night, this bias would have existed at both sites. A number of studies have shown blue crabs to be more nocturnally active (Ryer, 1987; Mense & Wenner, 1989).

Abundance of this species was significantly greater at Site 1, and this may have been due to availability of prey. As the planted S. alterniflora in Site 1 grew, L. irrorata

(Periwinkle snail) colonized the site in high numbers and were observed climbing the grass blades. These are a known prey item for blue crabs during high tide (Steele, 1979;

West & Williams, 1986). Although the numbers of snails recorded were higher in Site 2

(Table 3), the sampling did not include the large number of snails observed living in the marsh vegetation near Site 1.

Species diversity was actually higher at Site 2, which does not support the theory that the added structure would increase diversity. This may be a factor of (a) the close

83 proximity of the two areas, (b) the fact that the reef and marsh were very newly established and did not yet affect diversity, or (c) that sampling was restricted to open bottom. In some cases, created wetlands cannot achieve the goals anticipated by restorationists simply because some are mutually exclusive; the most highly productive wetlands are often monocultures and unable to attract a highly diverse faunal population

(Zedler, 2000), although diversity and production are often goals stated within the same projects.

While species richness was higher at almost every sampling event in Site 1 and greater as measured by the DIVERSE test, repeated measures tests showed it was not a statistically significant trend over time. One explanation could be that species richness is generally higher in low nutrient wetlands (Chapman et al., 1996, Zedler, 2000) whereas both sites within this study receive large inputs of nutrients from both natural planktonic sources and stormwater runoff that might mask site­specific differences (Thorpe et al.,

1997). Rozas & Zimmerman (2000) had similar findings, showing species richness and fish densities were not significantly different when marsh and nonvegetated marsh edge were compared. Since this investigation targeted open water species in both sites, the similar fish assemblages were anticipated, and there may have been no treatment effect.

The majority of fish captured in our study were under 5 cm, and Luckhurst and

Luckhurst (1978) found positive correlations between habitat complexity and species richness only for fish larger than 5 cm. However, fish surveys taken by Department of

Environmental Protection staff in the same locations in 2005 found an additional ten species exclusively in Site 1, including reef fish such as Lutjanus synagris (Lane snapper), Rhinoptera bonasus (Cownose ray) and several species of Coryphopterus

84 (Goby). Underwater video and anecdotal evidence by fishermen have indicated

Lutjanus griseus (Gray snapper), Mycteroperca spp. (Grouper), and large S. ocellatus

(Red drum) are populating the rock reef area in Site 1. While the three samples taken in

2005 showed no significant differences in numbers recovered between sites, Site 1 had twice as many species present. Although the later sampling involved greater sampling effort per event, the trend of increased species richness is a likely outcome of the create habitats maturing with time.

Along with species richness and diversity, site fidelity is another important factor to consider in the analysis of ecosystem restoration projects. Site fidelity of recruits and ontogenetic habitat shifts were unknown variables for this study, limiting the ability to address any differences in production between sites. Increases in fish sizes from sequential sampling were used to infer growth rates for M. cephalus (Striped mullet) and

L. rhomboides (Pinfish), assuming site fidelity. M. cephalus (Striped mullet) and L. rhomboides (Pinfish) spawn in late winter and early spring, and juvenile population increased in March for both species (FFWCC, 2005a; FFWCC, 2005b). Data suggests recruitment and growth as abundant Class 1 (0­4.5 cm) fish decreased in April commensurate with an increase in Class 2 (5­9.5 cm) fish (Figures 24, 25, 27, 28).

Mobility of the species sampled was an impediment to determining any site­specific growth differences, and no individuals were tagged or tracked to demonstrate site fidelity. Mobile species have many choices within a large bay to congregate and could easily have moved between Sites 1 and 2 or to and from the sites and the larger bay system. In addition, the size spectrum captured can be affected by predation and net avoidance. Youngest fish tend to be removed faster than larger fish by predators. Fish

85 larger than 5 cm may also be better at net avoidance. Large M. cephalus (Striped mullet) in particular were often observed jumping but rarely captured in the seine.

Given the limitations of the collection method, the data are not intended to be comprehensive for all species, but a relative reflection of any differences between sites.

Organisms within this study were collected by seine, but the net could roll over burrowing animals, and fast swimmers or those who cling to vegetation or rocks likely avoided avoid the net altogether (Rozas & Minello, 1997; Petrik & Levin, 2000).

Assessment of fish populations in clear water areas can be accomplished with visual surveys, but the typically turbid conditions of estuaries require trapping or catching of some kind (Williamson et al., 1994; Baltz et al., 1998; Petrik & Levin).

Most studies have found detectable patterns of increased overall abundance and species diversity for fish and crustaceans in habitats with structure compared with open bottom or damaged habitat. This study differed in that for open water sampling, proximity of marsh and reef resulted in no difference in overall abundance and species diversity. Size differences were generally not significant except for M. cephalus (Class

1), L. rhomboides (Class 2) in Site 1 and M. peninsulae (Class 3) in Site 2. The net excluded most large fish and weights were not measured in this study. Biomass may have differed between sites, which could indicate improved foraging success (Hunter­

Thomson, Hughes, & Williams, 2002). However, the greater species richness and enhanced recruitment of particular species of fish at Site 1 indicate the newly created habitat will likely contribute to fish production in this portion of Pensacola Bay.

A final contribution from this study was the ability to show significant differences in faunal density over time between sites in close physical proximity to one

86 another. Williamson et al. (1994) also noted that two adjacent habitats with different physical characteristics could exhibit a difference in species composition with obvious habitat preferences among the species present. By targeting open water species in this study, the specific habitat preference was less of an issue than the proximity of habitat and habitat complexity. By adding reef and vegetation to open water and creating complexity, species abundance improved for the majority of fish and blue crabs recovered. Given the focus on open water species that would normally be found at both sites, and the overriding influence of population and seasonal dynamics within the larger bay system, the ability to detect differences between these two sites based on an immature habitat creation project is dramatic. This research supports the ideas that increased habitat complexity improves juvenile recruitment and that the positive effects of marsh and reef creation can be indirectly carried into open water nekton populations in a shallow bay.

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101 APPENDIXES

102 Appendix A Map of FDEP Water Quality Sampling Locations

103 104 Appendix B Copyright Permission Letter

105 From: Cooey, Sally [mailto:[email protected]] Sent: Tuesday, July 10, 2007 3:54 PM To: Stevenson,Carrie T Cc: Boudreau, Darryl; Baldwin, Amy; Lappert, Jim Subject: Permission to use images

Dear Carrie,

The Florida Department of Environmental Protection has received your request to reprint the following material in your thesis/dissertation:

Pre­project GIS conceptual design map of Project GreenShores Aerial photo of Project GreenShores after placement of oyster breakwaters and intertidal areas Aerial photo of Project GreenShores water quality monitoring stations.

Pursuant to a public records act request, these images may be used for any lawful purpose. As a courtesy, we do request that our agency be the recognized source of these images.

Thank you for contacting us about the use of these images.

Sincerely,

Sally

Sally Cooey Public Outreach Department of Environmental Protection Northwest District ­ Pensacola 850­595­8300 x.1180 fax 850­595­8417 cell 850­777­0476