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MAP OF FISHERY HABITATS WITHIN THE VIRGIN ISLANDS BIOSPHERE RESERVE BIOSPHERE RESERVE RESEARCH REPORT NO. 8 RALF H. BOULON, JR. DIVISION OF FISH AND WILDLIFE DEPARTMENT OF CONSERVATION AND CULTURAL AFFAIRS GOVERNMENT OF THE U.S. VIRGIN ISLANDS U.S. DEPARTMENT OF THE INTERIOR NATIONAL PARK SERVICE AND VIRGIN ISLANDS RESOURCE MANAGEMENT COOPERATIVE VIRGIN ISLANDS NATIONAL PARK P.O. BOX 7789, ST. THOMAS U.S. VIRGIN ISLANDS 00801 LOCAL CONTRACTING AGENT ISLAND RESOURCES FOUNDATION RED HOOK BOX 33, ST. THOMAS U.S. VIRGIN ISLANDS 00802 (NPS CONTRACT NO. CX-0001-3-0048) Abstract REPORT NO.8 Subtask 2.1 MAP OF FISHERY HABITATS WITHIN THE VIRGIN ISLANDS BIOSPHERE RESERVE Nineteen naturally occurring and one man-made benthic community habitat types are described in terms of the commercially important fish species assemblages found occurring there. Marine habitat types were mapped for all of St. John from NOS (National Oceanographic Survey) aerial photographs and groundtruthed by divers from January to May 1984 to determine accuracy of mapping and to describe each habitat in detail. Fish species assemblages are determined using a random point, visual census technique which appears to be quite accurate, is easy» fast» and repeatable by anyone with minimal instruction. Results indicate that each benthic habitat type can be distinctly described in terms of its unique fish species assemblage and life history function. The life history function is viewed as a continuum primarily related to distance from shore and depth with habitats like mangrove shoreline and back reefs being juvenile refuges and deeper offshore habitats like lower fore-reefs and bank patch reefs being mature fish habitats where most reproductive activities take place. Habitat types similar to each other in species assemblage generally share similar structural complexity or structural components. Habitats with greater structural complexity tend to contain a greater number of species. In addition to demersal fin fish, lobster, conch and whelk are other heavily exploited fishery resources. Lobster populations appear to be quite low and appear to be highest in the deeper, more structurally complex habitats. Conch are less common in shallower habitats, possibly due to overfishing, but are frequently found in the deeper grassbeds seaward of coastal reef systems. With a limited, narrow habitat, which is very accessible to fishermen, whelk populations are extremely low with few large, mature individuals found. Both migratory pelagic fish species and baitfish require substantial work before enough is known to even attempt to draft management guidelines. ———— Tt TABLE OF CONTENTS FOREWORD, .. cc ccccccccccccccccrsensesescesersscccsecseer ee e® se ecees LIST OF TABLES ....--ceeececercrsrsererree reser eres INTRODUCTION. .secsececciecceeeces ce weccenecesessces eoeeseoaoevee eoeeceesee METHODS... 2eeeeeees cee cece cccenccesensecesenseseesseegeeeees 2.1 2.2 2.3 Commercially Important Fish SPeCLeS seavececescsovccssers Habitat Types Sampled......eeeeeecerereesersercrrrcrcccrs Census TeEChnique....cssscccccssrvecceseserverreccccccrs® HABITAT DESCRIPTIONS ..-.eeeccccccsssccoccrsscccrerssrercrcscrs 3.1 3.2 3.4 3.5 3.6 3.7 3.9 3.10 3.11 3.13 Subtidal Bedrock — SReeceececesssccecececcccecerececsecs 3.1.1 General Description ...cescecrcceesscereesrrercres 3.1.2 Fishery Description.....eecervececeeeserece eeeeee Mangrove Shoreline - Sm...sseeescercceececscccrccsscsces 3.2.1 General DeSCYiption...ccrewccncreessseseresceeses 3.2.2 Fishery DeSCLiption...escreevcceceosescsecesccre . Shallow Bay GrasS - Shqgeseecessevesssccecerresessscccens 3.3.1 General DeSCrIption .ccrecenserccesecsssnsececsres 3.3.2 Fishery Description... .cseceseceeeesecsccscrcceses Shallow Bay Pavement - SBpecwsvcresreeeccccccvsenscrscece 3.4.1 General DeSCKiption....sceeeececsereccrerscsoeoes 3.4.2 Fishery DeScription.--e-eeerreeseseseeccscecccrecs Back Reef — RDeweesesrserccce ee ec c erence wees seen aaesscese 3.5.1 General Description...«--. ae cccerene cee neee se ceee 3.5.2 Fishery DESCYiption...cecsececeseeesessesercecers Upper Fore-reef - Rfu Lecce ccceececeseerescccccees en eceee 3.6.1 General DeSCLIPtLON cece sees ec enc crereererarssvene 3.6.2 Fishery Description...... wees cees we eee nenee se eeee Upper Fore-reef on Subtidal Bedrock - Rfu II ...---.+.e-. 3.7.1 General. DeSCYIPtion .. cece rere r ever eveescsesacens 3.7.2 Fishery Description..... i ie ie a Upper Fore-reef/Fore-reef Pavement Ecotone - Rfu/Rfp.... 3.8.1 General Description .....cccccecsees ae cceeees ec eee 3.8.2 Fishery DeSCription ..ccerccseessccess ecco ee weccece Fore~reef Pavement ~ Rip I ..wseeseeesees ee ecee weer ccc ene 3.9.1 General DESCYIPCION .. wesc ccccer crc cccesnssseecens 3.9.2 Fishery Description .........- ec eeee Coe v cee receone Fore-reef Pavement With Ledges - Rfp II pccewseecesesccee 3.10.1 General Description ........+... i i a 3.10.2 Pishery D@SCription 2... cece c eee se ere vcccsercsece Lower Fore-reef - Rfl .....cceeee were reer ewe eeesccnce eee. 3.11.1 General Description .......cceeecne eee e sewer scene 3.11.2 Fishery Description..... ese c ce cccee ence eee seees Lower Fore-reef on Fore-reef Pavement - Rfl II .......... 3.12.1 General Description ...... eee mec wee c wrens ereeeeees 3.12.2 Fishery DeSCription ..ceeeecsescrssccrcccscecsenes Lower Fore-reef on Subtidal Bedrock - Rfl III .-.ce--. eee 3.13.1 General DESCKiPtion eerecsovesecersccccccccssseves 3.13.2 Fishery DeSCription oe ceccesecccesece cect eresesene Reef Gorgonian Flats ~ Rgo I .-eeseeeeees se eenne ccc cccnee 3.14.1 General D@SCLIPCION 2. cere e en nerssccccrecareseces 3.14.2 Fishery: DESCription weeecersccenccsvesees acc ceweee iii 1 4 4 7 8 11 1l il 11 16 16 16 17 17 22 22 22 23 23 23 24 25 25 25 26 26 26 27 27 27 28 28 29 29 30 30 31 31 32 33 33 33 34 34 34 35 35 35 CONTENTS (Continued) 3.15.1 General Description..........-......000.... 3.5.2 Fishery Description ......e....... cece 3-16 Shallow Bay Patch Reef - SBPY eee ecececccccccccecce 3.16.1 General Description ..................00,., 3.16.2 Fishery Description ....................,.. 3.17. Bank Pavement - BD tere eee cee c eee ecccnccccecceeene, 3.17.1 General Description .............02200.. eee 3.17.2 Fishery Description ...... ee eee cece c eee 3.18 Bank Gorgonian Flats - BQO ose c cece ccc nc ec cnsccacce 3.18.1 General Description .......... cece eee e ew eee 3.18.2 Fishery Description oc... eee e eee c eee cnn 3.19 Bank Patch Reef - BDL ese c cece ccc ec cece cn cnccncce 3.19.1 General DESCKIPtion -o ee eee cece ccccecccece 3.19.2 Fishery DESCLIption .eee ce rec cece cccccccuce 3.20 Shallow Bay Artificial Reef - SBAL eecessscccccccce 3.20.1 General DESCLIption oc... ee eee eee c ec een cnce 3.20.2 Fishery DESCYIption .secccccccicccccccccuae 3.15 Reef Gergonian Flats on Ledges ~ Rgo ID ee... eae, 36 36 36 36 36 37 37 37 38 39 39 40 40 40 41 42 42 42 44 49 50 53 FOREWORD Virgin Islands National Park was designated as an International Biosphere Reserve by the United Nations Educational, Scientific and Cultural Organization ( UNESCO) in June, 1976. However, the formal dedication did not take place until May, 1983. The standardized, single-page description of the area which was issued by UNESCO under the Man and the Biosphere Programs, MAB Project 8, in 1976 is entirely inadequate for the purpose of meeting Biosphere Reserve Objectives. The purpose of the present (VIRKC I) project was to provide more detailed descriptions of the Reserve's physical and biological features as well as certain aspects of human use, such as fishing and boating. Inherent in the concept of the Reserve is the belief that it is intimately related to the nearby British Virgin Islands and that it should also fit within a future multi-site Lesser Antillean Biosphere Reserve. The following reports are included in the VIRMC I Research Series Reports. The West Indies Laboratory (Fairleigh Dickinson University) prepared the reports for "Ecological Community Type Maps and Biological Community Descriptions for Buck Island Reef National Monument and Proposed Marine Park Sites in the British Virgin Islands, "Trends in Recreational Boating in the British Virgin Islands, A Preliminary Assessment of Impact from Human Activities on Anchorages and Development of a Monitoring Program for Safe Anchorages,' “Geographic Range and Research Plan for Monitoring White Band Disease;s' and “Marine Ecosystems of the Lesser Antilles - Identification of Representative Sites.’ The Division of Fish and Wildlife (Department of Conservation and Cultural Affairs, Government of the U.S. Virgin Islands) Prepared, "Map of Fishery Habitats Within the Virgin Islands Biosphere Reserve," "Fisheries Habitat of the Virgin Islands Region of Ecological Importance to the Fishery Resources of the Virgin Islands Biosphere Reserve, . Utilization of the Virgin Islands Biosphere Reserve by Artisanal Fishermen," and " Long-Term Monitoring of Fisheries in the Virgin Islands Biosphere Reserve." The Caribbean Research Institute (College of the Virgin Islands) Prepared, "Marine Community Descriptions and Maps of Bays Within the Virgin Islands National Park/Biosphere Reserve," and " Collection of Common Organisms Within the Virgin Islands National Park/Biosphere Reserve." The Island Resources Foundation prepared, “Assessment of Fish and Shellfish Stocks Produced in the Virgin Islands Biosphere Reserves "Socioeconomic and Cultural Role of Fishing and Shellfishing in the Virgin Islands Biosphere Reserve Area,’ “Characterization of Lesser Antillean Regional Fisheries, as well as the Synopsis and Executive Summary. Field work for the project was carried out during the period December, 1983, through October, 1984. Copies of the individual reports can be obtained from: The Virgin Islands National Park, Red Hook Headquarters, P.O. Box 7789, St. Thomas, Charlotte Amalie, VI 00801. qi LIST OF TABLES PAGE Table 1. Fish and invertebrates of commercial importance in the Virgin Islands Biosphere ReServe..--sserrererrcrereres 5 Table 2. Habitat types censused for commercially important species Of fish... eeceeeceeeeeecrccceeessseecerecers 9 Table 3. Number of individuals per commercially important species censused within each habitat type and their PELCENE OCCULTENCE. oc reer eceecvccceesreerercrecsseroes 12 Table 4. Average fish size per species per habitat type.......- 18 1ii 1. INTRODUCTION The insular shelf around St. John, U.S. Virgin Islands has representative examples of nearly every tropical marine environment from mangrove embayment to shelf edge reef. This diversity of habitats in turn supports a high diversity of fish species assemblages. This report attempts to define the marine benthic habitats in the Virgin Islands Biosphere Reserve on the basis of their utilization by commercially important species of fish, molluscs and crustaceans. Each habitat type is described separately and characterized in terms of significant species found there and the type of utilization being made of the habitat. It is generally accepted that marine habitat differences are due primarily to variations in substrate and that the difference in structural complexity results in differential use of these habitats by demersal fin fish species (Luckhurst and Luckhurst, 1978; Gladfelter and Gladfelter, 1978). Utilization ranges from mangrove lagoons as nursery grounds (Austin, 1971; Olsen, 1972) to offshore, deep reef reproductive or spawning grounds (Randall and Randall, 1963; Colin, 1978; Colin and Clavijo, 1978; Clavijo, 1983). Colin and Clavijo (1978) suggest that locations chosen for reproduction by reef fishes producing planktonic eggs may not be arbitrary. Rather, a selection process seems to take place where the most seaward extension of reefs may be chosen which allows the best opportunity for planktonic eggs to escape benthic egg predators and reach offshore circulation systems. The presence of a reef system provides shelter for the individuals engaged in reproductive activities. Coastal migratory pelagic fish species are found from shallow water reefs and even mangrove embayments to oceanic conditions (Centaur, 1982). There does not appear to be any species-specific benthic habitat preferences. Specific habitat description is further complicated by the fact that the specific location of larval development is unknown and little scientific information is EIS available on specific migration Patterns other than the hypothesis that general current patterns in the Atlantic May greatly affect the migration of pélagics. Although pelagic species are found throughout the shelf habitats, they do tend to appear more frequently and in greater abundances in the deeper water along the outer edges of these habitats. Little is known about the population dynamics or habitat requirements of bait fish in the Caribbean. These species are very important in the marine food web. - Not only do many fish species depend on them for food, but all species of seabirds depend on them for sustenance. The timing of migratory seabird arrivals may depend on coincident population peaks in the baitfish (Norton, R.L., pers. comm.). Habitat descriptions for the queen conch, Strombus gigas, have been published for a number of locations in the Caribbean (Randall, J.E., 1964; Percharde, 1968; Berg, 1975, Hesse, 1979). Adult conchs are found from grass and mud-bottom Mangrove embayments out to deep (10m +) algal plains. They are most often found in beds of seagrass (Thalassia testudinum, Syringodium filiforme, or a mixture of both), but are also commonly found on sand flats. Their occurrence on sand may be related to a need to bury themselves partially for shell deposition and for egg laying (Randall, J.E., 1964). Juvenile conchs are generally found in shallower water and in areas of less dense s@agr-ass, Young conchs may be re- stricted in their movement in thick beds of seagrass. The whelk or West Indian topshell, Cittarium pica, is primarily found in rocky, coastal habitats from Slightly above the water level to several feet below (Randall, H.A., 1964). They appear to prefer coasts that are : subject to at least some wave action. This may be due to the presence of cooler, well-oxygenated water. The smaller individuals tend to be found higher up in the habitat range of this species with larger, mature individuals being found in deeper (1-2m) subtidal bedrock or upper fore-reef zones. The spiny lobster, Panulirus argus is found in a variety of habitats. Olsen et al. (1975) found that mature lobsters appeared to be most abundant ————E———— near reef-grassflat boundaries. Juvenile populations were found in mangrove and Thalassia habitats. In the reef habitat, lobsters are primarily found in dens where they spend the daylight hours. At night, they forage for food either on the reef or on adjacent sandalgal plains (Herrnkind, et al, 1975). It is well known that the spiny Lobster engages in periodic migrations from the normal habitats where it is found to deep water areas. Primary work on this phenomenon has been done in the Bahamas (Herrnkind and Cummings, 1964; Kanciruk and Herrnkind, 1978) although the migrations occur throught the range of the species. Reports from local divers indicate that the phenomenon may occur in the U.S. Virgin Islands (R. Nose, personal communication). To date, there is no good explanation as to the biological significance of this event. In this report, the presence and abundance of commercially important species of fish will be used to characterize the marine benthic habitats in the Virgin Islands Biosphere Reserve. The different habitats will be described in terms of significant species found there and how the habitat is being used. 2. METHODS 2.1 Commercially Important Fish Species Species of fish were selected for study on the basis of their importance in the local commercial fisheries. Basically, any species taken as a food fish by any “Means was considered. Table 1 lists the species selected for this study. They include six (6) pelagic species, forty-three (43) species of demersal fin fish, two (2) species of baitfish, two (2) species of molluscs and one (1) crustacean. For the purposes of this study, the molluscs were noted on a presence/absence basis, and the crustacean is noted as total numbers observed per habitat type. All crustacean observations were incidental as a survey for this species was of a magnitude beyond the scope of this project. Nearly all species selected for this project are considered in the Fishery Mnanagement Plan for the Shallow-Water Reeffish Fishery of Puerto Rico and the U.S. Virgin Islands (CFMC, 1984). The species considered in the Fishery Management Plan were selected out of approximately one hundred eighty (180) which are landed and used in quantity throughout the Caribbean. ud ——— TABLE 1. Fish and invertebrates of commercial importance in the Virgin Islands Biosphere Reserve. COMMON NAME LATIN NAME cero mackerel king mackerel - kingfish/longmouth blue runner ~ hardnose bar jack - carang black jack greater amberjack DEMERSAL FIN FISH: queen triggerfish - ole wife blue-striped grunt white grunt french grunt tomate small-mouth grunt spanish grunt caesar grunt sailor's choice juvenile grunts Margate mutton snapper - virgin snapper dog snapper grey snapper schoolmaster - mango snapper yellowtail snapper mahogany snapper - burn tail queen & french angelfish - flatfish grey angelfish - flatfish rock beauty red hind - hind graysby - butter socks coney ~ butter fish mutton hamlet Nassau grouper black grouper tiger grouper porgies sea bream doctorfish and tang yellow goatfish - queen mullet spotted goatfish spanish hogfish - spanish piper parrotfish - goutou trunkfish - shellfish porkfish sea chubs spadefish barracuda snook white mullet - cramo Scomberomorus maculatus S. cavalla Caranx fusus C. ruber C. lugubris Seriola dumerili Balistes vetula Haemulon sciurus H. plumieri H. flavolineatum ~- H. aurolineatum H. chrysargyreum H. macrostomum H. carbonarium H. parra H. spp. H. album Lutjanus analis L. jocu L. griseus L. apodus Ocyurus chrysurus L. mahogoni Pomacanthus spp. P. arcuatus Holocanthus tricolor Epinephelus guttatus Petrometopon cruentatum Cephalopholis fulva Alphestes afer Epinephelus striatus Myctoperca bonaci M. tigris Sparidae Archosargus rhomboidalis Acanthurus spp. Mulloidichthys martinicus Pseudupeneus maculatus Bodianus rufus Scaridae Ostraciontadae Anisotremus virginicus Kyphosus spp. Chaetodipterus faber Sphyraena barracuda Centropomus undecimalis Mugil curema TABLE 1. (Continued) Fish and invertebrates of commercial importance in the Virgin Islands Biosphere Reserve COMMON NAME LATIN NAME DEMERSAL FIN FISH: squirrel fish Holocentridae mMojarra - sand diggers Gerreidae BAITFISH: ° blue fry - sweethead fry -Jenkinsia lamprotaenia red ear sardine - yellow bill Harengula humeralis . MOLLUSCS: queen conch Strombus gigas whelk Cittarium pica CRUSTACEANS: spiny lobster Panulirus argus 2.2 Habitat Types Sampled In collaboration with investigators on another project (Beets and Lewand, 1985) a series of maps were prepared for the marine benthic communities around St. John, U.S. Virgin Islands (Appendix I) with emphasis on those within V.1. National Park waters. The maps were prepared by drafting directly from National Ocean Survey aerial photographs shot in March, 1983. The photographs were enlarged to 76.2 cm by 76.2cm with a scale of 1:5300. Drafting acetate was placed over the photographs on a light table, and all coastal and marine features were inked onto the acetate. These maps indicate the boundaries of all distinct benthic communities from the shoreline out to extensive offshore homogeneous habitat or the deepest discern- ible benthic feature on the aerial photographs. Once all benthic communities had been established on the maps, a field sampling schedule was set up to determine the species of commercially important fish. found in each type of benthic community (hereinafter referred to as habitat type). Initially, all habitat types were inspected to determine which were significant to the fishery resources within the Virgin Islands National Park boundaries. It readily became apparent that a number of habitat types (e.g., Bank sand, Bank algae and others) either had no species utilizing them or so few and in such low numbers that the value of these habitats to the fishery resources was insig- nificant. These habitats were not sampled. Of those that appear to be signif- icantly utilized by the fishery resources within the National Park, twenty habitat types were selected for study (Table 2). Of these, thirteen are distinct habitat types. Four are areas made up of mixed habitat types where this mixture alters the species assemblage found in either of the two parent habitats. Two are habitat types with increased structural complexity due to the presence of ledges which alter the species assemblage found in the pure parent habitats. One is an artificial reef habitat and is included for DEE Y: SSO comparative purposes with Similar natural habitats. 2.3 Census Technique Habitats were sampled for commercially important fish species assemblages using a random point, visual census technique (Bohnsack and Bannerot, 1983). Census locations were selected on a haphazard basis within a habitat by attempting to locate oneself where only the desired habitat was Present within the census radius. At each census location, the observer would begin by facing in one . direction and during a five-minute period, rotate clockwise 360° » sampling all fish within an eight meter radius surrounding the observer. Due to good water clarity, we were able to use an 8m radius in all censuses made in this study. As the observer rotated, the number of individuals observed for each species was recorded on a preprinted form (Appendix II). The preprinted form saves time in writing down the species name. After using this form for a few times, the location of species’ name is easily remembered. The chance of counting an individual twice was greatly reduced by strictly adhering to the 360° census with no overlap. At the end of a sample period, the minimum and maximum length for each species was recorded. These lengths were estimates based on a pre-study test in which estimates were made of objects at various distances from the observer and then measured to determine accuracy. Most species of fish occurred in low numbers during a census. Schools of fish were counted as they appeared in the sample radius and if large, were counted in the 10's, 100's or even 1000's. Advantages of this method are numerous. It is simple, objective, repeatable, fast and easy to use. It is easily performed by anyone with a minimum of instruction and practice. It requires no complicated accessories such as cameras, transect lines, compasses, etc. As such, it is very applicable to developing third-world countries where technology is not available for higher-tech methods TABLE 2. Habitat types censused for commercially important species of fish. Acronyms used in all succeeding Tables. See text for description of habitat types. See also Beets and Lewand, 1985. Habitat Types * — Mixed habitat types + - Habitat types with increased structural +10. li. *12. *13. 14. +15. 16. 17. 18. 19. 20. SR Sm SBg SBp Rb Rfu I Rfu IT Rfu/Rfp Rfp I ‘REp II Rf1l fT REL II Rf1 Lit Rgo I Rgo II SBpr Bp Bgo Bpr SBar complexity due to ledges Subtidal Bedrock Mangrove Shore Zone Shallow Bay Grass Bed Shallow Bay Pavement Back~reef Upper Fore-reef Upper Fore-reef on Subtidal Bedrock Upper Fore-reef/Fore-reef Pavement Ecotone Fore-reef Pavement Fore~reef Pavement with ledges Lower Fore-reef Lower Fore-reef on Fore~reef Pavement Lower Fore~reef on Subtidal Bedrock Reef Gorgonian Flats Reef Gorgonian Flats on Ledges Shallow Bay Patch Reef Bank Pavement Bank Gorgonian Flats Bank Patch Reef Shallow Bay Artificial Reef 10 Tequiring many accessories. It is easily performed either snorkeling or using SCUBA (for depths greater than 4m). A Stationary observer has a better chance of observing more cryptic or wary species which would otherwise be scared away by a moving diver, thus biasing the data. Additionally, due to the small area actually sampled in one census, the chances of crossing habitats within a census are greatly reduced. The only requirement of this method is an underwater watch and an ability to identify fish species using external morphological or visual characteristics. This is easily accomplished after review of a good identification guide (Randall, 1968; Chaplin, 1972; Stokes, 1980). Several other methods were reviewed but not selected for this study due to complexity or due to sample area problems. Visual census methods for assessing fish assemblages began with a transect method (Brock, 1954), but this method is time consuming as the researcher is required to lay a line of appropriate length underwater. Jones and Thompson (1978) proposed a species-time method (Rapid Visual Technique) which does not require a line. Time is used in place of area and assumes that given more time, a diver can census a greater area and is thus exposed to more species. However, this method has been recently criticized (Sanderson and Solonsky, 1980; and others) and results from it should be carefully interpreted. Other methods of this nature such as the Visual Fast Count (Kimmel, in Press) were deemed unsuitable for the purposes of this present study as this study attempts to correlate fish assemblages with particular benthic marine habitats. As most habitats are fairly narrow in areal distribution, methods involving moving divers will easily carry the observer across discrete habitat boundaries or expose him to edge effects from adjacent habitats. Extremely hi-tech methods such as en- placement of time-lapse underwater movie cameras to record species within a particular area were not considered for practical reasons. While data from this method are excellent, the problems associated with the method make it impractical for general use (P.L. Colin, personal communication). — | 11 3. HABITAT DESCRIPTIONS 3.1 Subtidal Bedrock - SR 3.1.1 General Description Significant portions of the coastline of St. John are fringed by this habitat. It is primarily composed of exposed, eroded bedrock which underlies the adjacent island coastlands. This zone generally ranges in depth from zero to 3 meters but . in some cases may be found deeper. The rock surfaces are usually covered with an algal turf and low invertebrate cover. The most abundant invertebrates present include: Millepora spp. Palythoa caribbea, Porites asteroides,Acropora palmata, Montastrea annularis, Diploria clivosa, D. strigosa, Dendrogyra cylindrus, and Siderastrea siderea. Gorgonians and sponges are generally also present. Live coral cover in this zone generally is around five to ten percent. 3.1.2 Fishery Description Although this habitat is found from shallow, protected bays to exposed rock points, the fish community supported by it remains relatively the same. A comparison of the extremes in location would undoubtedly show the presence of certain species which are more commonly associated with one extreme or the other (e.g., blue runner on rocky points and trunkfish in protected bays). Twenty.fish censuses in this habitat detected twenty-nine species of commer- cially important fish (Table 3). Of these, only four species occur frequently enough to be species of significance (most abundant in this habitat), These include . yellowtail snapper, coney, doctorfish and Parrot fish. Other species of potential significance(moderately abundant)include porgies, yellow goatfish and squirrelfish. Blue fry are fairly common in this habitat and attract individuals or schools of blue runner, mackerel and carang. The average size per fish of the significant species here is smaller than in more seaward habitats (Table 4). 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Ly LT iT 62° Ls° +0€ st WHaAUCOW OOT' oL* oT eb" TT’ o0o°T Ly 98T 00°T 02" os* ety Lid os* Ls* eT" se° oT HsTatTaminds Lv LATION eT" MOONS 02° 02° 30° S 80° ee* Lv Oz° oT" oT’ wanowad va zo" 6T HsragdvdS aeqs adg o3q adgs 11084 I 08% Il tT ti 134 I tap dz I dyy dyu (nya IL ya I ayy a dgs 3as wag us adAL AIVLIGVH (° W090) "€ 8TIeL The West Indian topshell or whelk (Cittarium pica was observed occasionally in this habitat. Individuals observed here were generally larger (greater than 10cm) than those observed in the intertidal zone. 3.2 Mangrove Shoreline — Sm 3.2.1 General Description This habitat type occurs in several of the deeper, more protected embayments around | . St. John. These include Fish Bay, Great Lameshur, Coral Bay, Hurricane Hole ard Mary's Creek. Small stands of mangroves also occur in Haulover Bay, Little Lameshur and Brown Bay. This habitat generally represents an area of low energy where wave action is baffled by the prop roots of Rhizophora mangle. These prop Toots serve as substrate for communities of encrusting organisms such as sponges, tunicates, tree oysters and algae. The bottom under and near these prop roots is usually sand or mud with leaf litter on the top, but may also include some sub- tidal bedrock. The complexity produced by the Prop roots additionally provides shelter from predators for juvenile fish. 3.2.2 Fishery Description The very protected, low energy nature of this habitat makes it ideal as a nursery habitat for many species of commercially important fish. Seven censuses and three species list compilations produced a list of twenty-five species of commercially important fish (Table 3). Many of these were very abundant and can thus be . considered species for which this habitat is significant as a nursery or juvenile development area. These include french grunt, tomtate, dog snapper, schoolmaster, yellowtail snapper, mahogany snapper, doctorfish, yellow goatfish, parrotfish and mojarra. The presence of many blue fry, generally of quite small size (lem) indicates that this is an important habitat for them as well. The large numbers 17 of unidentifiable juvenile grunt supports the nursery habitat hypothesis. The average size of fish per species in this habitat gives the greatest evidence for the theory that the mangrove habitat is a nursery habitat. Except for species unique to this habitat, all species present had an average size less than the average size per species for all habitats (Table 4). Several species were observed here that were not observed in any of the other habitats. These include sea bream, snook and red-eared sardine. These species undoubtedly exist in other habitats but were not observed during a census. Juvenile conch (Strombus gigas) were also observed in this habitat in Hurricane Hole. One young lobster with a carapace length of less than 3 inches was observed. 3.3 Shallow Bay Grass - SBg 3.3.1 General Description Many of the shallow bays around St. John have sand bottoms which are colonized by communities of sea grass. In general the communities consist of mixed stands of Thalassia testudinum and Syringodium filiforme with occasional patches of Halodule wrightii. Many species of algae may also be present including Halimeda spp., Penicillusspp., and others. The low structural complexity provides little shelter for fish. The infaunal and epifaunal communities present (molluscs, echinoderms) provide a food resource for several species of fish. It is not uncommon to see Large eagle and other rays foraging on the bottom of these grass beds often accompanied by one or more trunkfish picking through the detritus for smaller food items missed by the ray. These grass beds have also been shown to be important in the nocturnal foraging of many species found on the reefs during» the day (eg. grunts and snappers forage for food in the grassbeds at night (Hobson, 1973)). set T 9 INNYD HSINVds | “et “9 , Pur $z 0¢ oot INNES HINOW-TIMs "et “IT “OT POTD 2 ]62 T Sz z 002 oot {1 iz €E Sot RIVENOL ° ee Let “zee [erst “Et 9 [A erLeu “9 | wrrt Le z ssz oy” loon T 9 T Les |e 6t0 zoe“ | cos | cee] sce 98t / | ea Innu9 ponaaa | Leer eet eet pes Yer aet at etl eet Lest "S “tt [Are *L Fad Fad lL Fa BST Fog “jor OT Lz 6L Te 0s T T INQYD GETHM “974 [06 v°St 1°21 GET Let “ST “OT “st L°eT ST eT tT “it tk b 6 9 8 9% € 8 INNYD dadTdis-a07¢ | $°9T S'lz Ces ot Let at Let ‘oz SOT oz “OT Fad "0z see Wr st 8 T s Y T HST.MIOOTUL ngzaNd e707 “ete u°te boc | “6'se 1° TE "Gz ees z | WOVCYaEHY £°ES vise t yore wv : b'sz sree Ue S WA S T La ‘9 S ss” | ve 8 oz “129 onwavo O*6T Tez €:02 Bez Ye StIA Tbe B27 Lee Lbesz |“ s'tz 6°12, £07 | erez | 1 sree T € WaNNNY SNE (4 it: arts t VA t HSTZONIN “9° 907 6°09} “OL Tee WA e t T z 8 T 9 s TRIDOW . 9°00 | “Sor | “s" se oor | “ssel B°9EL“b-0e | “Le Lost 39 ; Tt oT t L *Z T 6 | 2z 2 zs z Sz € z zT 9 t S t 6T g a0 : : dsu K aj 7Pas ada | o6g dq adag j1ro6u | ro6u [rrr tzu] rr tzu] 1 tya| 11 a 1 dga yoga {TE OFA |T oH bs das bas wg as “suofjeuetdxs wkuo10e 103 7 aTqey 39s *pezinds0 sazoads yotym ut S3eIFqey JO Aequnu Aq paptatp iearqey 3zad azts oBeranr g “wAUotIe adkq IeITqQey MOT@q PeIPOTpUT aIeWT Ise UT pasn sasnsued jo aiequny UST JO Aequnu sazeotpuz ysets Teuoseyp. x47 moteq szaquny co Cane) ' ‘sido Ue. 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WaLsaol . HONGO TOT st SNIGUYS Gguvs-dad ToT : Ria ante €°0% T 8 8 z 6 $ T 4 oe > WASWCOW Ot e°za 7 £°0g “oz /G0e ps7] £02 | “oz O'S “1z Let ff oot ot T 8 Tt € 98T fa t T bz 6 v T OT HSTITRUINGS : zstl/7est{ “est “2 'St 1°72 sou “4e'stl “2'stl “2° St 1°21 ‘stl z7t] “ort “OT “el o°SZ 9 LaTION “Sz pO z YOONS “OE z°9L T ¢ S z T z T z wanowauwa z°9L)/% 8° £8 ‘ £001 S*s89o] “612 ma: "16 ‘L GES a°ez S 6 HSTdaavds e7Lt 67Lt Pgs adg o8q dg | adas [rr o8¥] 1 ofy TID |sy tra ]r tay {Et Gay t dra aya 11 ey r sy Ww das 34s as as ddl LVLIGVA wa ‘978 ("3u09) «6° # BTqQeL 22 3.3.2 Fishery Description Five censuses in this habitat type revealed the paucity of fish present during the day (Table 3). Five species of commercial importance were observed. The most common family observed was the trunkfish family, generally browsing on the bottom for molluscs and other infaunal invertebrates. The trunkfish censused and observed in the Shallow Bay Grass tend to be of a larger size than in other habitats. It is not uncommon-to see 12 inch trunkfish in this habitat. Other commercially important fish species observed occurred infrequently and are probably transients rather than residents. The only fish observed consistently in these grass beds is the bucktooth parrotfish, Sparisoma radians, although this species does not generally attain a size or abundance to make it commercially important. | Conchs were also observed occasionally in this habitat, primarily as ju- veniles. Some of these locations were Fish Bay, Brown Bay, a small bay east of Leinster Bay, Mary's Creek, Great Lameshur Bay and Huricane Hole. 3.4 Shallow Bay Pavement - SBp 3.4.1 General Description Many of the shallow bays around St. John have pavement areas within them not associated with any adjacent reef systems. These are fairly flat, featureless bottoms of hard carbonate substrate sometimes covered by a thin sand veneer. Occasional coral heads, sponges and gorgonians may be present. Upraised portions of the carbonate substrate may be colonized by algal turf. Common coral species found here include M. annularis, S. siderea, A. agaricites and PB. porites. Some of the bays in which this habitat type occurs include Reef Bay, Grootpan Bay, Hawksnest Bay, Honeymoon Bay and Maho Bay. 23 3.4.2 Fishery Description Low structural complexity results in low numbers of fish found in this habitat. In general, fish observed in Shallow Bay Pavement were found associated with coral outcroppings or other areas having some vertical relief. Seven censuses in this habitat detected a total of seventeen commercially important species of fish (Table 3). Species having a high percent occurrence in this habitat include carang, doctorfish, parrotfish and squirrelfish. Less abundant species include blue-striped grunt, yellowtail snapper, red hind and spotted goatfish. Blue fry were fairly common in the Shallow Bay pavement and could account for high percent occurrence of carang. Nassau grouper, while not occurring frequently here, are more abundant in Shallow Bay Pavement than in any other habitat sampled. In general, species occurrring in Shallow Bay Pavement are smaller than the total average fish size for all habitats sampled (Table 4). This habitat, like Subtidal Bedrock, may be a transitional habitat between the inshore nursery areas and the offshore habitats. Coneys here are larger and Nassau grouper are smaller than in any other habitat. 3.5 Back Reef -— Rb 3.5.1 General Description This habitat is principally located behind fringing reefs which are separated _ from shore by a shallow (1.5m maximum) lagoonal area. Generally this is a very protected area behind an emergent or nearly emergent reef crest. In many cases, the back reef slope to the bottom of the back reef lagoon is very steep and composed of large interlocking pieces of dead Acropora palmata which provide good shelter for the many species of fish found here. The floor of the lagoon is usually colonized by extensive stands of Porites furcata, P. porites and 24 P, divaricata. Also occurring here are M. annularis, P + asteroides and Millepora spp. Good examples of this habitat type occur in Fish Bay, Reef Bay Mennebeck Bay and to a lesser extent in Mary's Creek.. 3.5.2 Fishery Description The protected nature of a back reef makes it an ideal resting site for large daytime schools of fish. Nineteen species of fish were detected in six censuses (Table 3). Species with high percent occurrences in this habitat include french grunt, tomtate, schoolmaster, yellowtail snapper, mahogony snapper, doctor- fish, yellow goatfish, parrotfish and squirrelfish. Blue-striped grunt also were present in moderately high numbers. Relative to most other habitats sampled, there was a noticeable lack of the predatory species. The constricted nature of most back reefs may preclude their presence. The one exception to this was a 1.7m blacktip shark that was seen behind the reef at Reef Bay in 1.2m of water. The shark was obviously there due to the presence of large quantitites of prey fish. Several species of grunts were observed in this habitat that were present in few or no other habitats sampled. These include small-mouth grunt, spanish grunt and caesar grunt. Additionally, this is the only habitat in which mullet were observed although it is known that they also frequent mangrove areas and shallow bays. The nearly even distribution between fish greater than or equal to the average size per species for all habitats (10) and those less than the average size per species for all habitats (8) (Table 4) would support the hypothesis that this habitat is a daytime resting area rather than a nursery area. The primary species of fish utilizing this habitat are species that leave the reef at night to feed in adjacent sand and grass flats. The single very large individual trunkfish observed in this habitat was seen in Reef Bay and may have been more closely associated with the extensive grass beds in the inshore portion of the back reef lagoon. 3.6 Upper Fore-reef - Rfu I 3.6.1 General Description This habitat is found near shore in many localities around St. John, usually in the seaward, shallow (less than 3m) portions of fringing or barrier-type reefs. It is primarily composed of the highly branching coral A. palmata, but may have other species present including, P. porites, P. asteroides, A. agaricites, Diploria spp., and Millepora spp. The predominance of A. palmata produces a structurally complex habitat with good refuge capacity. Because of this complex- ity, this habitat (like the Back Reef habitat) serves as a principal daytime refuge for many species of fish that forage away from the reef at night in the adjacent grass beds and pavement areas. The best developed examples of this habitat type occur on the north shore at Johnson's Reef, Windswept Beach, Mennebeck Bay and along the shoreline in various locations as narrow fringing reefs. The south side appears to have been well-developed examples of this habitat in Fish Bay and Reef Bay. At present, these areas show evidence of storm damage, probably from Hurricanes David and 25 Frederic in 1979 and Allen in 1980, but are showing some evidence of recolonization. 3.6.2 Fishery Description Twelve censuses in the Upper Fore-reef I detected twenty-two species of commercial- ly important fish (Table 3). The primary species utilizing this habitat are four species of grunts (french grunt being predominant), three species of snapper ‘(yellowtail snapper being predominant) and the usual doctorfish and parrotfish in high numbers. Most other species detected were present in fairly low numbers. There were no unique species noted for this habitat. Blue fry were present in relatively high numbers. Whelk were occasionally seen here, usually as large, 26 older individuals (greater than 9cm in diameter). The species assemblage in this habitat is somewhat similar to that found in the back reef habitat. Fourteen species are shared between these habitats, including many that forage away from the reef at night and seek refuge in the reef during the day. Several more oceanic-type fish (carang, queen triggerfish, coney, angelfish) occur in the Upper Fore-reef while several of the less common grunt species and lagoonal species such as the mullet are absent. The majority of species in this habitat have an average size smaller than or equal to the total average size per species for all habitats (Table 4). This could suggest the transitional nature of this habitat for many species from the inshore nursery grounds to the offshore reproductive areas. Schoolmaster - snapper are the only species occurring in this habitat which is of a size larger than or equal to the size in all other habitats. 3.7 Upper Fore~reef on Subtidal Bedrock - Rfu II 3.7.1 General Description This habitat is a mixed zone composed of an upper fore-reef type habitat growing on a basement of subtidal bedrock. When present, it occurs immediately adjacent to a rocky coastline. The combination of these two zones produces a habitat with physical characteristics of both (high structural complexity on top and rock surfaces below having high algal cover and low numbers of invertebrates). The predominant coral in the upper portion is A. palmata with Millepora, P. caribbea, A. agaricites, D. strigosa and others present. . 3.7.2 Fishery Description From the union of these two habitats, one would expect to see a fish species 27 assemblage representative of both habitats. Due to the rarity of this mixture, few censuses were made (Table 3). With two censuses we can only detect the most common species (ten observed). With the exception of spanish grunt, all species observed in the Upper Fore-reef II were present in either Upper Fore-reef I or Sub-tidal Bedrock or both. There is nothing notable about fish sizes in this mixed zone habitat (Table 4). 3.8 Upper Fore-reef/Fore-reef Pavement Ecotone - Rfu/Rfp 3.8.1 General Description This habitat represents a transition between an upper fore-reef habitat and a fore-reef pavement habitat. It is dealt with as a separate zone due to the unique features of the fish species assemblage observed here. The primary ex- ample of this ecotone is found at the eastern end of Cinnamon Bay. Right adjacent to shore are found several large patches of A. palmata which appear to have produced large colonies extending from approximately 3.5m in depth to .3m in depth. Only the upper surface of these mounds are living. Tunnels extend several meters back into the mounds. The sides may be colonized by Millepora, Palythoa caribbea, A. agaricites and other corals. 3.8.2 Fishery Description The habitat complexity resulting from this particular combination of features provides a unique form of shelter uncommon to either habitat type. As a consée- quence, a high number of commercially important fish species (18) apparently use this habitat (Table 3). Species with high percent occurrence for this habitat include carang, blue-striped grunt, french grunt, grey snapper, yellowtail snapper, doctorfish, yellow goatfish, parrotfish and sea chubs. A number of species 28 were observed here that were not detected in either of the two contributing zones. These include small-mouth grunt, mutton snapper, grey snapper and porkfish. Those species present in the contributing zones but not observed in the ecotone may show up with more censuses. Nearly all the species present in this ecotone were of a larger average size than the total average size of the species for all habitats (Table 4). In Particular, these include mutton snapper, grey snapper, parrotfish, barracuda and mojarra. Schoolmaster had an average size equal to the largest size found for any habitat. Location may be a factor here in that low or no fishing pressure may allow individuals to grow large at this site. 3.9 Fore-reef Pavement - Rfp I 3.9.1 General Description This habitat occupies more area around St. John than any other nearshore, hard- bottomed habitat. In general, Fore-Reef Pavement I can be described as any relatively flat, hard, carbonate bottom having low percent live cover of corals and other sessile invertebrates. This pavement must be associated with a reef system are defined as either shallow-bay pavement or bank pavement (see Section 3.17). Fore-reef pavement generally has a very low degree of structural complexity which provides little shelter for fish. Sessile organisms characteristic of this habitat include M. annularis, P. asteroides, S. siderea, Diploria spp., many gorgonian species and others. Overall gorgonian cover is below 25 percent. Portions of this habitat type may be covered by a thin sand veneer and appear to be a sand bottom with occasional coral or gorgonian outcroppings. ———— 3.9.2 Fishery Description Twenty-five censuses in this habitat detected twenty-six species of fish (Table 3). Although this appears to be a high number of species for a habitat with low structural complexity, it can be noted that very few species had high percent occurrences or numbers of indiviudals. Only five species occurred in greater than 30 percent of all censuses done in this habitat. They include carang, french grunt, yellowtail snapper, doctorfish and parrotfish. And of these, only doctorfish and parrotfish had percent occurrences over 40 percent and they were both 100 percent. Numbers of individuals were also very low for the less abundant species (percent occurrences less than 30 percent). These statistics would indicate that while many species of commercially important fish can be found in this habitat, it is only an important habitat for a very few species. Other species may use it as an avenue between other adjacent habitat types or may be present there only when space or food is limiting elsewhere. Some species may utilize it for foraging but reside elsewhere. Blue fry were found here occasionally, mostly in shallower areas. Large, mature whelk were observed occasionally on the sides of algal covered dead coral mounds, primarily in shallow water (less than 3m). During this study, five lobsters were observed in crevices or sand bottom caves under coral mounds in this habitat. The majority of fish in this habitat (17) had a size equal to or larger than the total average size of the species for all habitats (Table 4). These size data suggest that this habitat is less of a transitional habitat than some of the nearer shore habitats. More of the individuals found here are mature. 3.10 Fore-reef Pavement with Ledges - Rfp II 29 30 3.10.1 General Description This habitat has nearly the same general description as that for fore-reef Pavement I. Fore-reef Pavement II has areas where ledges have been formed either through uplifting of the carbonate substrate or erosion and undercutting. This anomaly is treated as a separate habitat even though it occupies very little of the total area of Fore-reef Pavement I, because the structural complexity created by the existence of ledges produces an unusual abundance and presence of some fish species which does not occur in Fore-reef Pavement I. Examples of this are on the west side of Ram Head or on the north side of Mary's Point. 3.10.2 Fishery Description Only two censuses were made in this habitat type. While not enough to quantify differences from Fore-reef I, they do point out that differences do exist. Sixteen species of fish were detected (Table 3) of which fourteen were also found in Fore-Reef Pavement I. The two species which occurred here but not in Fore-Reef Pavement I were the mahogany snapper and spanish hogfish, both of which seem to prefer habitats with high structural complexity. The most abundant fish were schoolmaster, doctorfish and parotfish. The latter two were the most abundant fish in Fore~Reef I. The schoolmaster possibly is more abundant here due to the increased shelter available. The ledges additionally provide habitat for lobsters which were observed in both locations. As with Fore-Reef Pavement I, this habitat appears to be less of a transition- al habitat than those previously described. Thirteen of the species observed had average sizes larger than or equal to the total average size for the species for all habiitats (Table 4). The mahogany snapper here had the largest average size for all habitats sampled. Yellow goatfish had an average size equal to the eee 31 largest average size found in any of the habitats. 3.11 Lower Fore-reef - Rfl lt 3.11.1 General Description This habitat type is very common around St. John. It forms the seaward border of most reef systems where they drop off into deeper water. However, because the . Lower Fore-reef is defined more in terms of coral cover and composition than location or profile (Beets and Lewand, 1985), considerable variation exists. It can be found as an extremely dense, well-developed patch of Montastrea annularis in a shallow bay (Kiddle Bay) to a near vertical drop-off with high coral cover on the offshore edge of an extensive reef system (Johnson's Reef). This habitat can be described as that portion of a reef having high percent live coral cover (greater than 20 percent), decreased gorgonian presence and sometimes steep slopes to deeper shelf sand, grass or algal plains. The most common coral species in this habitat include M. annularis, M. cavernosa, Colpophyllia natans, S. siderea, A. agaricites, Diploria spp. and Mycetophyllia Spp. In shallow areas where light penetration is good, the head corals can form large domed colonies with overhangs that produce good shelter for fish and lobster. In deeper areas, colonies tend to be flattened to maximize light capture. The steeper slopes in the deeper portions of this habitat are generally more eroded and have numerous crevices and overhangs which provide good shelter for many . species of fish. 32 3.11.2 Fishery Description Fifty-two censuses in this habitat detected forty species of commercially important fish (Table 3). We chose to do more censuses here because of this being a fairly common and very interesting habitat. The high number of species detected may be partly a function of the high number of censuses, although the data suggest that this may only be the case for a few species. A number of species have a high percent occurrence. These include carang, blue-striped grunt, french grunt, yellowtail snapper, grey angelfish, red hind, doctorfish, parrotfish and squirrelfish. Moderately abundant species include white grunt, schoolmaster, yellow goatfish, spotted goatfish and spanish hogfish. As would be expected, the number of pelagic species observed was higher than any other habitat. These include mackerel, blue runner, carang, black jack, and amberjack. Black jack and amberjack were only observed in Lower Fore-reef. This habitat also supports a large number of lobsters in the Many crevices and caves present. Of the forty species of fish detected in this habitat, 32 species had an average size larger than or equal to the total average size per species for all habitats (Table 4). This would suggest that this habitat supports mature, reproductive individuals with few juveniles and sub-adults. Further supporting this hypothesis is the number of species found here with larger individuals than in any other habitat. These include queen triggerfish, small-mouth grunt, dog snapper graysby, porgies, sea chubs and spadefish. Nassau grouper had a size equal to the largest found in all other habitats. 33 3.12 Lower Fore-reef on Fore-reef Pavement - Rf1 II 3.12.1. General Description Where this habitat is found it can be described as large M. annularis or C. natans mounds up to 8 m in diameter located on fore-reef pavement. This is treated as a separate habitat due to the possibility of both Lower Fore-reef and Fore-reef Pavement I influencing fish species composition. The structural complexity found in the Lower Fore-reef portion of this habitat would attract abundances of fish not attracted to the Fore-reef Pavement I. The Lower Fore-reef acts as a patch reef in the midst of a less productive area. 3.12.2 Fishery Description Having only two censuses in this habitat makes it difficult to draw conclusions about the similarity or dissimilarity between this habitat and either of the two contributing habitats. From Table 3 we can see that all species detected in this habitat were also detected in Lower Fore-reef I. All species but one (tiger grouper) were also detected in Fore-reef Pavement I. Without more data it is questionable as to whether this should be treated as a distinctly different habitat, however, the possibility exists that these areas are concentrating fish from the sur- rounding Fore-reef Pavement. From size data (Table 4) no clear conclusion can be drawn concerning similarity of Lower Fore-reef II to either Fore-reef Pavement I or Lower Fore-reef I. Eight of the species in Lower Fore-reef II have an average size larger than or equal to the total. average size per species for all habitats which may indicate that fish in this type of habitat tend to be larger, more mature individuals, as found in Lower Fore-reef. 34 3.13 Lower Fore-reef on Subtidal bedrock - Rf1 III 3.13.1 General Description This atypical habitat generally occurs in shallow water (less than 3m) along a rocky coastline such as the east side of inner Great Lameshur Bay or at the north end of Waterlemon Cay in Leinster Bay. It is composed of well-developed coral Stands producing a Lower Fore-reef environment on Subtidal Bedrock. The presence of these dense stands of coral alters the structure of the Subtidal Bedrock sig-~ nificantly. This modification of structural complexity should have an effect on the composition and. abundance of the fish assemblage normally found in Subtidal Bedrock. 3.13.2 Fishery Description Few censuses were made in this uncommon habitat. A low number of censuses makes comparative analysis with the two contributing habitats difficult. _ Two censuses in Lower Fore-reef III detected thirteen species of commercially important fish (Table 3). All species observed in this habitat were also observed in Lower Fore-reef I and Subtidal Bedrock. Some species such as red hind and black grouper were detected in few other habitats than the three mentioned above. This may demonstrate some relationship between these three habitats. Of the thirteen species detected in this habitat, seven have an average size greater than or equal to the total average size per species for all habitats (Table 4). This may suggest a mix between the transition habitat (Subtidal Bed- rock) and the habitat used for reproduction (Lower Fore-reef I). When comparing this habitat to the two contributing habitats, we find that ten of the species present have average sizes smaller than or equal to the species’ average size in Subtidal Bedrock. This indicates that this habitat is a mixed habitat influenced by both contributing habitats and that possibly the Subtidal Bedrock has a slightly 35 higher level of influence, perhaps due to depth range (less than 4m). 3.14 Reef Gorgonian Flats - Rgo I 3.14.1 General Description This habitat is very similar to and occurs in the same position on the reef as fore-reef pavement and is distinguished by having high percent gorgonian cover (greater than 25%) and reduced coral cover. It generally occurs in areas of high cur- rent such as Hawksnest Point, Whistling Cay and in portions of the Narrows, presumably because the high transport of particulate matter provides a rich nutri- ent source for the filter-feeding gorgonians. The low structural complexity provides little shelter for fish. Additionally, the dense canopy formed by the gorgonian "forest" allows less light to reach the sandy substrate for algal growth and thus reduces food resources for herbivores. This in turn may reduce food resources for some of the more carnivorous species of fish. 3.14.2 Fishery Description Nine censuses in this habitat only detected nine species of commercially important fish (Table 3). This demonstrates the depauperate nature of the fish fauna in this habitat. Only two species occurred here in relatively high abundance and these are doctorfish and parrotfish. Red hind was moderately abundant. Of the nine species occurring here, seven species had an average size smaller than or equal to the total average size per species for all habitats (Table 4). This would suggest that this habitat is either a transitional or sub-optimal habitat which supports fish during life stages between juvenile and mature or is composed of individuals attempting to locate a suitable habitat. 36 EE SESS So 3.15 Reef Gorgonian Flats on Ledges - Rgo II 3.15.1 General Description This habitat is generally the same as Reef Gorgonian Flats I with the exception of numerous ledges created by uplifted substrate or erosion and undercutting. This increases the structural complexity of the Reef Gorgonian Flats I and provides shelter for fish species that are more cryptic. 3.15.2 Fishery Description One census is insufficient to characterize the fish community in this habitat but it does indicate the presence of certain species that are most likely present due to the increase in structural complexity. Of the nine species detected in this habitat, six were not detected in the Reef Gorgonian Flats I (Table 3). Most of these species are species that are usually found in crevices and under overhangs. These include tomtate, margate, black grouper and tiger grouper. The sand bottoms under the ledges may account for the presence of yellow goatfish as they feed in sand. Lobsters were also observed utilizing these ledges for shelter. As opposed to Reef Gorgonian Flats I, the majority of species found in Reef Gorgonian Flats II were larger than or equal to the total average size per species for all habitats (Table 4). These species were primarily the ones not found in Reef Gorgonian Flats I. It would seem then that the ledges provide habitat suitable for mature individuals of certain species. Those species also found in Reef Gorgonian Flats I may be utilizing this habitat for the same reasons as hypothesized for Reef Gorgonian Flats I. 3.16 Shallow Bay Patch Reef - SBpr 3.16.1 General Description A shallow bay patch reef is generally a small reef occurring within the confines 37 of a shallow bay and isolated from shore and other reef systems by sand or seagrass. They can range from an actively growing shallow (less than 3 m) reef 4 m in diameter (Cinnamon Bay) to a storm damaged, sparsely colonized reef (Cinnamon Bay) to a larger (approximately 40 m in diameter) deeper (10 m) actively growing reef (Hawksnest Bay). What they all share in common is that they are an island of structural complexity in the middle of an area of flat featureless bottom. Thus, fish are attracted to them for shelter and daytime refuge. 3.16.2 Fishery Description Five censuses in this habitat detected twenty species of commercially important fish (Table 3). Species for which this habitat appears to be important include carang, biue-striped grunt, french grunt, mahogany snapper, grey angelfish, doctor- fish and parrotfish. Carang were primarily present in the deeper patch reef censused. Four species of grunts plus many unidentifiable juvenile grunts were observed in this habitat. They are undoubtedly utilizing this habitat as a daytime refuge near the sand and grass beds where they forage at night. Likewise, the mahogany snapper are utilizing these patch reefs as a daytime refuge. Grey angelfish and spotted goatfish were primarily observed in the deeper patch reef censused. Due to the fact that three of the earlier censuses (deeper patch reef) for this habitat had no length data recorded, the average size for each species may not be truly reflective of this habitat as a whole (Table 4). It can be noted however, that the average size for the main species found in the shallower patch reef is smaller than the total average size per species for all habitats. This would suggest that these shallow-water protected patch reefs may be somewhat of a nursery or early transition habitat for some species. 3.17 Bank Pavement - Bp 3.17.1 General Description Bank pavement habitats were defined as areas of hard, carbonate bottom seaward of 38 any near shore reef systems. In most Bank Pavement observed this bottom type has many raised ridge areas on it which are undercut to form ledges. This undercutting provides a fair amount of shelter for fish and lobsters. -Living cover on. Bank Pavement is generally quite low (5~10%). Coral species found here include M. annularis, S. siderea, A. agaricites and M. cavernosa.. Many gorgonians, sponges and black corals May be present. Depths are generally quite deep (greater than 20m) . This habitat extends over much of the insular shelf region outside of the National Park Service boundaries. 3.17.2 Fishery Description Seven censuses in this habitat type detected twenty-six species of commercially important fish (Table 3). Species having high numbers or high percent occurrence in this habitat include queen triggerfish, blue-striped grunt, french grunt, grey snapper, yellowtail, grey angelfish, coney, doctorfish, parrotfish and squirrelfish. Species which are more common in this habitat than in any other habitat include queen triggerfish and coney. In fact, through personal observations and reports from knowledgeable divers, it appears that this may be the principal habitat for the queen triggerfish which may be the most important commercially caught trap fish. A complete examination of the contents of twenty-two randomly selected fish traps in St. Thomas showed that 22 percent of the total catch was made up of queen trigger- fish (Clavijo, et al. 1984), higher than for any other species. These abundances are in spite of relatively high fishing pressure as fishermen move offshore from the overfished inshore areas. As with other deeper water habitats a higher number of pelagic species are Present such as mackerel, kingfish and carang. The presence here of four species of grunts and four species of snappers indicates that this may be an important daytime refuge for species foraging at night in the nearby sand flats and algal plains. 39 The numerous ledges present on the ridges of Bank Pavement provide substantial habitat for lobsters and the currents present in many of these areas provide a mechanism for larval dispersal. Many of the areas fished commercially for lobster north, south and west of St. Thomas are areas of raised bottom possibly composed of Bank Pavement. Twenty of the species found in this habitat had average sizes greater than or equal to the total average size per species for all habitats (Table 4). This supports the hypothesis that the deeper habitats support populations of larger mature fish and that these habitats may be the reproductive habitats where many of these species spawn and the pelagic eggs have a good chance of dispersal by the currents. A number of species found in this habitat had a larger average size than in any other habitat in which they were observed. These include blue-striped grunt, white grunt, french grunt, yellowtail, doctorfish and Porkfish. For. these species, this habitat may be an important source of larvae for the shallower water, more near shore habitats. This may also be the case for the lobster popu- lation present there. A male lobster weighing approximately 4800 grams was taken from this habitat during the study. This was the largest lobster seen in a long time by any of the investigators involved in this study. 3.18 Bank Gorgonian Flats - Bgo 3.18.1 General Description This habitat is very similar to Reef Gorgonian Flats I except that it is not bounded on its seaward side by a reef system. It generally is a relatively flat, hard bottom area with high (greater than 25%) gorgonian cover and low structural complexity. This habitat appears to be rather patchy in distribution and appears to occupy areas with good current. As with Reef Gorgonian Flats I, this may be due to the filter-feeding nature of gorgonians and their need for water transport of nutrients. Examples of this habitat are on the north side of Mary's Point, around 40 the Durloe Cays and a large patch northeast of the eastern tip of Mary's Point. 3.18.2 Fishery Description Only one census was-made in this habitat which makes it difficult to compare the results with other habitats or to draw strong conclusions about the fishery compo- sition. However, when comparing the species present in Bank Gorgonian Flats with the species observed in Reef Gorgonian Flats I, a strong similarity can be seen (Table 3). Five of the seven species detected in Bank Gorgonian Flats are also found in Reef Gorgonian Flats-I. Of these, the most abundant species detected in Bank Gorgonian are also found in Reef Gorgonian Flats I. Of these, the most abundant species were doctorfish and parrotfish with all other species occurring only occasionally. With more censuses Bank Gorgonian Flats would probably exhibit even greater similarity to Reef Gorgonian Flats I. In general, most fish in this habitat appear to have an average size larger than the total average size per species for all habitats (Table 4). This must be treated cautiously as the low number of censuses can produce misleading information. 3.19 Bank Patch Reef - Bpr 3.19.1 General Description A bank patch reef in general is a discrete reef system, usually circular in shape, separated from shore and other reef systems by sand, grass or algal plain. They may have significant vertical relief (up to 10 m or more in elevation from the surrounding bank) and range in size from several meters to nearly 300 m in diameter, Examples of these variations can be found south of St. John off Reef Bay. Larger bank patch reefs usually have a flat upper surface which may be sparsely colonized compared to the nearly vertical sides. The sessile invertebrate commun- ities in Bank Patch Reef are generally of a deeper water composition similar to Lower Fore-reef I. Dominant species of corals include M, annularis, 41 M. cavernosa, C. natans, A. agaricites, S. siderea, Diploria spp. and Madracis spp.. Percent living cover can be quite high (60 to 70 %) with few gorgonians. Bank patch reefs appear to serve as islands of refuge on an otherwise fea- tureless bottom. They may harbor many thousands of fish that seek vertical struc -ture to provide shelter primarily from predators. Many of these fish species may venture off the reef at night to forage in the surrounding sand, grass or algal flats. This foraging by fish and feeding by invertebrates maintain a sand zone around patch reefs that are situated in a grass bed or algal plain. This feature is very distinctive and aids in identification of patch reefs from aerial photographs. 3.19.2 Fishery Description While not a very common habitat, particularly within the boundaries of the National Park, these patch reefs appear to be a very important habitat on the shelf regions around St. John. They provide shelter for many species of fish in an area where shelter is not otherwise available. Ten censuses in this habitat detected twenty- eight species of fish (Table 3). Many of these species had high numbers of indi- viduals or high percent occurrences. It is these species in particular for which this habitat appears to have great significance as a refuge. These species include queen triggerfish, blue-striped grunt, white grunt, french grunt, grey snapper, yellowtail, mahogany snapper, grey angelfish, red hind, coney, doctorfish, yellow goatfish, parrotfish and squirrelfish. This habitat also attracts some pelagic species such as carang, mackerel and kingfish. The presence of five species of grunts and four species of snappers provides evidence that this is an important daytime refuge for nocturnal foragers. Several species have a higher number of individuals and percent occurrence in this habitat than in any other habitat sampled. These include carang, grey angelfish and red hind. Queen triggerfish are nearly as common and abundant here as in Bank Pavement. 42 _ Lobsters are also found in this habitat. The complexity here is similar to Lower Fore-reef I and provides adequate shelter for lobsters. Of the twenty~eight species of commercially important fish detected in this hab- itat, twenty-one have an average size greater than or equal to the total average size per species for all habitats (Table 4). This suggests that this habitat supports Mature, reproductive fish similar to most of the other deeper water, offshore habitats. Only kingfish and sailor's choice have larger average size in this habitat than in any other of the other habitats sampled. 3.20 Shallow Bay Artificial Reef - SBar 3.20.1 General Description This habitat is unique in that there is only one shallow bay artificial reef known in National Park waters. It is included here for comparative purposes with natural Shallow bay patch reefs, although all sampled are situated in slightly different environmental settings. This reef was set in place by John Randall in 1960, as a study of recruitment onto an artificial patch reef (Randall, 1963), and later studied by Ogden and Ebersole (1981). It is situated in Little Lameshur Bay in the middle of a dense seagrass bed. The reef is composed of standard concrete building blocks which have since become scattered over an area approximately 15 m in diameter. The greatest vertical relief is nearly .5 m. The blocks provide shelter in their core holes for a variety of fish and invertebrate species. 3.20.2 Fishery Description One census in this artificial reef detected twelve species of commercially important fish (Table 2). The most abundant species observed were white grunt, tomtate and squirrelfish. Mutton hamlet were observed here in significant numbers. This species was not observed in any other habitat during this project. Size comparisons with other habitats (Table 4) are not possible due to the single census and the occurrence of only single individuals for several species. 43 44 4. DISCUSSION The only mapping project of any magnitude around St. John prior to this one and the one reported by other workers in this Project series (Beets and Lewand, 1985) was carried out by Kumpf and Randall (1961). Their product was a map showing the Major marine environments of St. John to the 10~fathom curve. While their map has served as a valuable aid to researchers for many years, we feel that the maps produced in this project series provide a level of detail far greater and should serve as a valuable aid for researches desiring to locate a particular habitat type. Definition of a pure habitat type is in many cases quite difficult, particular -ly when dealing with motile species such as fish. Most habitats appear as part of a continuum of habitats where a pure habitat only exists if it is large enough to have a core area free from edge effects caused by adjacent habitats. Adjacent habitats may have chance occurrence of some species as a result of the proximity to a habitat where it is more common. It is for this reason that species of significance in a particular habitat are defined as those species which have a percent occurrence of greater than 30 percent. If a species occurs in one or more than one census out of three, then this species is probably commonly found in this habitat. When each benthic habitat type is considered in terms of its significant fish species, we See a relatively distinct species assemblage for each major habitat type. While some major habitat tyPes may appar somewhat similar in species composition (e.g., Reef Gorgonian Flats I and Bank Gorgonian Flats), we find that this is because the two habitats share similar structural complexity .or structural components. We also see that habitats with greater structural complex- ity tend to contain a greater number of species. This is most likely due to the increased amount of available shelter. Additionally, the occurrence of within zone variations of species assemblage (presence of "exotic" species) many times are due to variations in structural complexity. Examples of this are ledges or an area of high relief in a habitat that by description has low relief and little “4 45 structural complexity (e.g., Reef Gorgonian Flats II). The matter of uniform sample size may have some affect on the number .of species observed in each habitat type. We can assume that, given enough censuses any habitat may eventually have had present it it at one time or another, all of the species of fish listed in Table 1. However, the censuses range from one to fifty-two for the different habitats. A subsequent study by the author where ten consecutive censuses were made in the same location indicated that 80 percent of all species detected during 10 censuses were detected after four censuses. Ninety percent were detected after eight censuses. Therefore, we can say that fish assemblage descriptions for habitats with less than four censuses are representative of the most common species in the habitat but not necessarily good descriptions of the entire commercially important species assemblage using the habitat. Species occurring in greater than 30 percent of all the censuses in a particular habitat can be said to be species of significance and used to describe that habitat in fishery terms. If we look at the various habitat types in terms of their utilization by the fish species assemblage present, we can note three major categories: nursery habitat, transition habitat and habitat used by reproductive individuals. Size data give a basis for the definition of these habitat categories. Nursery habitats (e.g., Shore Mangroves) are low energy, protected areas where juvenile fish can aggregate in a location relatively free from predation. Juvenile fish move into the areas as they settle out of the larval phase. As they reach some critical size or state of physiological development, they move out into the transition habitats (e.g., Upper Fore-reef, Fore-reef Pavement) where they may spend the majority of their sub-adult like. While some fish reach maturity and may repro- duce in these transition habitats, most fish seem to be of a larger size in the deeper, offshore reproductive habitats (e.g., Bank Patch Reef, Lower Fore-reef, Bank Pavement). It is in these habitats where most fish having pelagic eggs apparently carry out reproductive activities. None of these habitats are absolute 46 in terms of providing a species with all of its daily requirements with the possible exception of the nursery habitat. There May exist daily migrations for certain species or individuals to deeper habitats for reproductive purposes while the rest of the time is spent feeding in shallower habitats (Randall and Randall, 1963). Although differences in fishing pressure between habitats may influence sizes of individuals observed, it is felt that this may not be very important as most fishing methods (traps or line) are not very selective by size. Although some fishermen do throw back the small fish caught, few may survive due to the trauma of the capture and subsequent handling. Coastal migratory pelagic species were detected in many of the habitats sampled. It was noted that a greater number of pelagics (mackerel, kingfish, blue runner, carang) were observed in the deeper, offshore habitats than the inshore habitats. This is as would be expected from our scant knowledge of pelagics. The carang is the only pelagic species which appears ubiquitous. The coastal migratory pelagics deserve special attention. The fact that we know so little about their life histories and stocks could lead the fisheries unit into a critical state before we learn enough to Manage it. Habitat areas of particular concern for this fisheries unit include: offshore areas of peak spawn- ing activities, all habitats along migration routes that support populations of bait fish, and reef complexes which support high levels of primary marine productiv ~ity (Centaur, 1982). Bait fish were primarily observed in the shallower, more protected habitats. One factor that may bias this observed habitat preference is that bait fish tend to occur near the surface. When sampling deeper habitats, the surface is further away and is outside the census. In shallow areas, the surface is visible from the diver's census location and the bait fish are visible. Lobster populations appear to be higher in the deeper, more structurally complex habitats. A juvenile lobster was seen in the Mangroves in Hurricane Hole supporting the fact that lobsters utilize mangrove habitats as nurseries. During 47 the time period of this study, we had reports from local divers that the lobsters were migrating away. These observations were based on a sudden large decrease in numbers and not on observation of an actual migration. This may have resulted in a lower number of lobsters seen during the course of this study than are normally present. Conch populations appear to be larger than expected. Juvenile abundances were quite high in several locations. Adult populations were observed in many deeper areas seaward of reef systems, on grass, sand or algal covered bottoms. Whelk definitely require immediate management attention if any are to be around for the future. Very few were observed during this study. Of those seen very few were large, mature individuals. Cursory examination of the data collected in this study indicates some differ- ence in species abundance between bays on the same coast. These questions require further analysis of the data already acquired and possibly collection of additional data. The methods utilized in this study for the mapping of fishery habitat appear to be quite reliable and cost efficient. The use of color aerial photographs for initial mapping of benthic marine habitats is extremely easy and effective. Through groundtruthing, one develops the capability of defining benthic: habitats from the aerials on the basis of color, location and texture. The census method utilized appears to be quite accurate, is easy, fast and repeatable by anyone with a minimum of instruction. Additionally, it requires no major equipment other than SCUBA for deeper (greater than 4m) work and an underwater watch. Unless some other census method is developed which provides statistically better data with little or no extra disadvantages over this method, I would recommend this method for surveys of the larger, commercially important species as they tend to be less cryptic and not affected by a stationary diver. Additionally, a stationary observer will detect those species which are initially cryptic but become visible after a short period of time (coney, hind). Some practice with objects of known size at different distances is necessary to be able to estimate fish size with some degree of accuracy. 48 49 5. ACKNOWLEDGEMENTS This project was funded by the National Park Service, Contract No. CX-001-2-0048 (Work Order No. PX-0001-3-0885) and administered by Island Resources Foundation in conjunction with the Virgin Islands Resource Management Cooperative (VIRMAC). In addition to direct funding, the National Park Service provided immeasurable assis- tance in the form of a field technician, Ms. Vonnie Small, use of a Park Service boat for all field work, SCUBA tanks for all underwater work, and use of Park Service facilities as temporary office space. This assistance made the project possible. Special thanks also are due to Mr. James Beets and Mr. Lance Lewand who assisted in portions of the field work and with whom many discussions have led to ideas presented in this report. Dr. Arthur Dammann also provided much appreciated advice and technical support. Dr. Robert Brander made possible these projects in the first place and to him go thanks for all his effort. Ms. Sandra Tate and Ms. Charlene Vaughan had to struggle through my handwriting to type this. 50 REFERENCES Austin, H. M., 1971. A survey of the ichthyofauna of the Mangroves of western Puerto Rico during December 1967 to August 1968. Carib. J. Seci., 1l (1-2): 27-39. Beets, J. and L. Lewand. 1985. Marine Community descriptions and maps of bays within the Virgin Islands National Park/Biosphere Reserve, St. John, USVI. Bert, C. J. Jr., 1975. Behavior and ecology of conch (Superfamily Strombacea) on a deep subtidal algal plain. Bull. Mar. Sci., 25:307-317. Bohnsack, J. A., And Bannerot, S. P., 1983. A random point census technique for visually assessing coral reef fishes. In: C.A. Barons and S.A. Bortone (Editors), The Visual Assessment of Fish Populations in the Southeastern United States: 1982 Workshop South Carolina Sea Grant Consortium Tech. Report 1, SC-SG~TR-01-83, pp. 14-17. Brock, V. W., 1954. A preliminary report on a method of estimating reef fish populations. J. Wildl. Mgmt., 18:297-308. Caribbean Fishery Management Council, 1984. Draft Fishery Management Plan, Regulatory Impact Review, and Environmental Impact Statement for the Shallow-Water Reeffish Fishery of Puerto Rico and the U.S. Virgin Islands. N.M.F.S., NOAA, DOC, 67 pp. Centaur Associates, Inc. 1982. Draft Fishery Management Plan, Draft Environ- mental Impact Statement and Regulatory Analysis for the Coastal Migratory Pelagic Resources. Prepared for the Caribbean Fishery Management Council, 201 pp. Chaplin, C.C.G., 1972. Fishwatchers Guide to West Atlantic Coral Reefs. Harrowood Books, Penn., 65 pp. Clavijo, I. E., 1983. Pair spawning and formation of a lek-like mating system in the parrotfish Scarus vetula. Copeia, No. 1:253-256. » Brandon, M., Tobias, W., 1984. Fisheries Statistics for the Virgin Islands (Preliminary Completion Report, Segments 1 to 5), N.M.F.S., PL 88-309, 2-335~R-5, Commercial Fisheries Research and Development, 55 pp. Colin, P.L., 1978. Daily and summer-winter variation in mass spawning of the striped parrotfish, Scarus croicensis Bloch. Fishery Bull., 76(1):117-124. » and Clavijo, I.E., 1978. Mass Spawning by the spotted goatfish, Pseudopeneus maculatus Bloch (Pisces: Mullidae). Bull. Mar. Sci., 28(4) : 780-782. Gladfelter, W.V. and Gladfelter, E.H., 1978. Fish Community structures as a function of habitat structure on West Indian patch reefs. Rev. Biol. Trop., 26(Suppl.1):65-84. Herrnkind, W.F. and Cummings, W.C., 1964. Single file migrations of the spiny lobster, Panulirus argus (latreille). Bull. Mar. Sci. Gulf. Carib., 14(1):123-125. Herrnkind, W.F., VanDerWalken, J.A. and Barr, L., 1975. Population dynamics, ecology and behavior of spiny lobster, Panulirus argus, of St. John, U.S.V.I. :(IV) Habitation, patterns of movement and general behavior, result of the Tektite Program, Vol. 2, Bull. Nat. Hist. Mus. L.A. County, No. 20: 31-45. Hesse, K.O., 1979. Movement and migration of the queen conch, Strombus gigas, in the Turks and Caicos Islands. Bull. Mar. Sci., 29(3):303-311. Hobson, E.S., 1973. Diel feeding migrations in tropical reef fishes. Helgolander wiss. Meeresunters, 24:361-370. Jones, R.S. and Thompson, M.J., 1978. Comparison of Florida reef fish assemblages using a rapid visual technique. Bull. Mar. Sci., 28:159-172. Kanciruk, P. and Herrnkind, W., 1978. Mass migration of spiny lobster, Panulirus argus: Behavior and environmental correlates. Bull. Mar. Sci., 28 (4) : 601-623. Kimmel, J.J., in press. A new species-time method for visual assessment of fishes and its comparison with established methods. Environ. Biol. Fish. Kumpf, H.E. and Randall, H.A., 1971. Charting the marine environments of St. John, U.S. Virgin Islands. Bull. Mar. Sci. Gulf. Carib., 11(4):543-55. Luckhurst, B.E. and Lockhurst, K., 1978. Analysis of influence of substrate variables on coral reef fish communities. Mar. Biol., 49:317-324. Ogden, J.C. and Ebersole, J.P., 1981. Scale and community structure of coral reef fishes: A long-term study of a large artificial reef. Mar. Ecol. Prog. Ser., 4:97-~103. Olsen, D.A., 1972. A survey of the fishes of the St. Thomas Mangrove Lagoon area. Part A. Unpublished Preliminary Report. » Herrnkind, W.F., and Cooper, R.A., 1975. Population dynamics, ecology and behavior of spiny lobster, Panulirus argus, of St. John, U.S.V.I.:(1) Introduction and general population characteristics. Results of the Tektite Program, Vol. 2, Bull. Nat. Hist. Mus. L.A. County, No. 20:11-16. Percharde, P.L., 1968. Notes on distribution and underwater observations of the molluscan genus Strombus as found in the waters of Trinidad and Tobago. Carib. J. Sci., 8:47-53. Randall, H.A., 1964. <A study of the growth and other aspects of the biology of the West Inidan Topshell, Cittarium pica (Linnaeus). Bull. Mar. Sci. Gulf. Carib., 14(3):424-443, Randall, J.E., 1962. Tagging reef fishes in the Virgin Islands. Proc., G.C.F.I., 14:201-241. , 1964. Contributions to the biology of the queen. conch, Strombus gigas. Bull. Mar. Sci. Gulf. Carib., 14:246~295. , 1968. Caribbean Reef Fishes. T.F.H. Publications, Hong Kong, 318 pp. 52 Randall, J.E., and Randall, H.A., 1963. The spawning and early development of the Atlantic parrot fish, Sparisoma rubripinne, with notes on other scarid and labrid fishes. Zoologica 48:49-60. Sanderson, S.L. and Solonsky, A.C., 1980. A comparison of two visual survey techniques for fish populations. Pacif. Sci., 34:237. Stokes, F.J., 1980. Handguide to the Coral Feef Fishes of the Caribbean. Lippincott and Crowell, New York, 160 pp. APPENDIX I 53 ae food WF ey, ~ air] ts tas LE 91105 EBL —e q $ 3 « 4 a Aeg oayuing us bulod IsausymeH WH e5eag ote *a ‘ 6 Aeg jeobwey “ne ‘a Ca6i SON ‘SsudesBoj;oyug feisoy . @3snag 9c a all a | —I 7) SIdIAW UI aJeIg r " t u ooe ood T oor c dVW IASN ‘uYyor “1g SaHluNWWOD oYyjuag auLEW 2h 9 12084 8s e ee iy” ZOE einjorg C861 SON ‘sydesBojoug teysay "81010" UH eFE2g ooe o0z oot 9 dVWN fASN “uYyor “Is SeyuNWWOD s}yJueg oULeEYW Avg umoig e%get 09 MAP 9 18°20' Johnson Bay Marine Benthic Communities St. John, USVI MAP 10 18°20 or) a: ~ cA _ z os Ae yoreus Onn tw mW uv we us z| a N thy anu keg S,uswyoues4 we 7 nie ‘ “ites TT) 4 on ¥u L wy / ar oa a ew fa : Z ~ ww av88 es tw / oe , Cw Vd 19355 . Gon Sater bossy Tetay |. ; F ‘ pres j sitods “ § Lesoye We aNEOG ustae fp! se0000 O; =~ ue . — SSI BIoVOL ‘Pua ISOM ay; ae vee 106 901 a me : us i. ™ ose YAGa nyo IS \ — Er D NOD DYyWWAG auEW 89 Dive Times? Location: 70 APPENDIX II SAMPLE DATA SHEET Radius Scanned: NUMBER OF INDIVIDUALS (Including maximum/minimum size) Description of habitat with list of dominant inver:e- brates. ‘Record depth; time of census and percent live coral cover Queen Triggerfish Blue striped Grunt White Grunt French Grunt Mutton Snapper Dog Snapper Grey Snapper Lane Snapper Schoolmaster Yellowtail Snapper Mahogany Snapper Angel fish Red Hind Graysby Coney Nassau Grouper Yellowfin Grouper Porgies Blue-Tang Doctor/Surgeon Fish ene Yellow Goatfish Spotted Goatfish Hogfish Spanish Hogfish Parrotfish Trunkfish Black Margate Carang Blue Runner egquirrelfish Barracuda Others (List) a 64°48! 18°21! Rada Cay undary St. John , USVI MAP 1 Marine Benthic Communities Aerial! Photographs NO (6) 100 200 300 t 1 4 er C = i a | Scale in Meters Source S.1983 —— Ss Turtle Bay Scott Bay]. nr | 18°21 APPENDIX I 53 21! 18 an 3.6 Hawksnest Point Ss Turtle Bay Ss SBs 64°47! Marine Benthic Communities St. John, USVv} MAP 2 0 100 200 a Cc | a | Scale in Meters Source: Aerial Photographs, NOS, 1983 Bs Profile 3.7 Hawksnest Bay “sR Peace Hill — SR 18°21 64°47! € dv¥W GG NPS Bounda: 56 64%5! Mary’s Pt. Salt Pond SBo-Sy/Halod a Francis Bay Marine Benthic Communities St. John, USVI Map 4 Source Aerial Photographs,NOS. 1983 Profile 3.201 57 Marine Benthic Communities St John, USVI MAP 5 0 100 200 300 Scale in Meters Source Aerial Photographs. NO S.1983 Waterlemon Cay Se \ NN 18°22" Salt Pond 6 4°42! 18°22 Bgo | Protile 3.17 Brown Bay Marine Benthic Communities St. John, USVI N MAP 6 (a) 100 200 300 — ——— Scale in Meters Source Aerial Photographs, NOS.1983 Bg-Sy Bs ‘ N ——] < o ® e Profile 3.20.2 J Salt Pond SR A a SR )f Boo Rtu wl, SR ane Hole 6401 K ! — ~ N \ \\ eco \ | \ \\ | i} Rt SBp ) Re vd Protile 3.18 /® q Sg @ Mennebeck Bay Profile 3.20.3 ) ff Gower aN a D Y Se Profile 3.19 Se X \ oS OA N sm AR \ Salt Pond Risse {/ Haulover Bay - St John, USVI MAP 7 Roo/SBg Newfound Bay Marine Benthic Communities 64°40" East End Sait rons, Sait Pond Salt Pond Privateer Pt. Qe 2 East End Pt. — Marine Benthic Communities St. John, USVI MAP 8 e 100 200 300 Scale in Meters Aerial P 09 18°20' Johnson Bay Ss Marine Benthic Communities St. John, USVI MAP 10 100 200 300 rT j E = — Scale in Meters fe) | Source: Aerial Photographs, NOS. 1983 64°42! 18°20! fos) os 2r— x o9 64°43! 1 Salt Pond ¢ Europa Bay Profile Profile 3.23 White Pt. s 18°19! SBo-Th NPS Boundar a ry ae 64 Marine Benthic Communities St. John, USVI meshur Bay MAP 12 39 N 9 190 200 0 Cc E = reater Lameshur Bay Scale in Meters Source: Salt Pond Aerial Photographs,NOS.1983 LY Profile 3.24.2 Protile 3.24.3 S8g-Th/Sy yPorney Bight 2 Grootpan Bay Cabritte Horn Pt. Kiddel Bay Profile 3.25.1 Profile 3.24.4 Puod 11eS 65 6 ates’ Marine Benthic Communities | SBo-Hal St. John, USVI SBo-ThiSy MAP 13 Reef Bay ° 100 200 300 L 1 1 a | Cc om =j Scale in Meters Source Aerial Photographs, NOS .1983 White Cliffs Y Protile 3.22 18°10 64%ar' — Great Cruz Bay Salt Pond » 8Be Patches Contant Pt. y J, ff Salt Pond —7, Blasbalg Pt. Maria Bluff 18°19" 66 Marine Benthic Communities St. John, USVI MAP 14 100 200 300 — ——— a | Scale in Meters zo (\+ Pond Rendezvous Bay 18°19! 64%s' Stevens Cay zc> Marine Benthic Communities St. John, USVI MAP 15 9 100 200 300 Cc Scale in Meters Source Aerial Photographs, NOS. 1983 Gallows Point Frank Bay 8e 8B La Pond Turner Bay — 89 Enighed Salt Pond SBe SR Contant Pt. a 64%s' L9 18°23 West End, Tortola Steel Pt. Little Thatch Cay 68 64°42! SBg-Th AY Sm Pn 0 106 26 at i i es | Dredge | NS nn | i" Seater Metres Spoils y hour Marine Benthic Communitie: | 1 : Bank o ~—S> Aerial Photugrsgrs MS SR : Frenchman's Cay 64°42! 69 64°sa' z Marine Benthic Communities St. John, USVI MAP 17 ° 100 200 300 Scale in Meters Source Aerial Photographs. NOS. 1983 54°aa Little Thate