ATOLL RESEARCII BULLETIN NO. 386 ISSUED BY NATIONAL MUSEUM OF NATURAL HISTORY SMITHSONIAN INSTITUTION WASHINGTON, D.C., U.S.A. JANUARY 1993 MANGROVE SWAMI'S IN BERM lJDA BY MARTIN L H THOMAS Abstract Bermudian m:rngrovc swamps at 32"N arc floristically s i~ni lar to those in thc Gulf of Mexico a t 23"N, both being composed of the red mangrove, Rhizophorn mangle, the black mangrove,Ariccnnio gernlinans and thc buttonwood, Conoctrrpus erec/u.s with the Brazil pepper tree, Schinus tcrcbinlhifolia invading. Thc most frequent associated flora arc the rcd alga, Bostqxhicr nzoninpei and green algae Rhizocloniunz riycrrrunz and R. kcrnerr and thc flowering plants, A.sparngus spwngcri, Borrrrhin fruicsccns and Sesuviunz por~~rloctrsir7tnr. The faunal components are vcry diverse and vary greatly among swamps. Mangroves of coastal bays show typical plant lonation but the trcc stands of inland saltwater ponds are typically non no specific with cithcr R. nznnglc or A. gcrminnns, and the associated flora and fauna Yery spomdic. Once establishcd, red o r black mangroves rcsist invasion and occupy a zone characteristic of both species. INTRODUCTION The mangroves of Bermuda at 32"N are the most northern in the Altlantic (Chapman 1977), their presence being fostered by the warm waters of the Gulf Stream which give the islands a warm, frost free climate (Anon. 1974, Morris el al. 1977). In the North Pacific, mangroves occur as far north as 35"N in Japan and on a world-wide basis those furthest from the equator are at 37% in New Zealand (Walsh 1974). The Bermuda mangroves are isolated, generally small in size and confined to an archipelago of very small land area. The only large swamps are the so-called "Great Mangrove" of Hungry Bay and another around Mangrove Lake (Fig. 1). Bermuda mangroves like other isolated and outlying examples, for example in Japan and New Zealand (Walsh 1974) are low in tree diversity. Only three species occur, Rhizophorn nznrzgle L., the red mangrove, Avicerzrlin gennirznrzs (L.) L., the black mangrove and Coizocnrps erectus L., the buttonwood (Britton 1918). Early accounts that included the white mangrove, Lngurzcularia rncemosa Gaertner (Lefroy, 1884) are probably in error (C. erectus being locally called the "white mangrove") even though more recent accounts still include it (Verrill 1902, Hanlon et al. 1975). The mangrove communities of Bermuda have never been described but aspects of plant components were mentioned by Verrill (1902), Harshberger (1905), Britton (1918) and Taylor (1960). Sterrer (1986) describes many of the commoner fauna and flora. Marine Research Group, University Of New Brunswick, Department of Biology, P.O. Box 5050, Saint John, New Brunswick, E2L 4L5, Canada. M;muscript received 3 October 1990; revised 27 March 1992 An unusual feature of the mangrove swamps of Bermuda is that about one third of them a re located around inland salt-water ponds, the majority of which a re tidal and connected to the sea by submarine fissures. These a re anchialine pools according to Por (1985). Although mangrove communities in Bermuda have not been mapped before, there is no doubt that they were formerly inuch more widespread. They are mentioned in early writings (eg. Lefroy 1884, Verrill 1902) and place names, still currently used, reflect their former presence. For instance, there a r e now no longer any rnangrcrves in "FJangrove Bay" on the west coast. Mangrove bark was used by early settlers in tanning as well as for fuel, additiom~ally they were cleared for coastal ct NI. 1981). Once cleared. mangroves a re generally slow to The locations of mangrove swamps in the Bermuda Islands was determined by reference to 1:2500, Series E811 topographic maps of Bermuda, information from the Bermuda Dept. of Agriculture and Fisheries, and by personal inspection of likely locations. Fringing mangroves, on rocky shores, dominated by C. crectzss were not considered as swamps. At each location where there were more than 10 trees containing either or both of R. mriizgle and A. gcrinitzuizs, the perimeter of the swamp was mapped by measurement and the use of optical rangefinders, with reference to landinarks appearing on topographic maps. T h e edge was defined as the outer limit of the canopy of trees or the community of halophytic plants typical of mangroves, whichever extended further. Areas were determined from the maps produced. O n e to 25 line transects, depending on the size of the swamp were run at right angles to the general shoreline, at low tide, from the back of the mangrove to either, the seaward extent of the canopy, the centre of the main drainage channel, o r the opposite side of the swamp, depending on site characteristics. O n each transect, elevation levels were determined at points where the gradient changed or a t 5 m intervals, whichever was less, by optical leveling and, beyond the water line, by depth. For bay and lagoonal tidal sites (Table I) , heights were corrected to chart datum, by the method of Anon. (1985). For anchialine ponds, tide readings were taken from staff gauges installed in each pond (Thomas et al. 1991) and corrected to a datum of mean low tide level. For non-tidal sites, datum was taken as the normal water level. Along each transect, the first and last occurrences of all macroscopic species were measured. For mangrove trees the following additional points were fixed: the start and end ofA. germiizarzs pneumatophores, canopy, trunks and seedlings; the start and end of R. rrta~zgle prop roots, canopy, trunks and seedlings; and for C. erectus and Sclziizus terebirztlzifolia (L.) the limits of the canopy. At five meter intervals, starting at the landward edge, for each tree species, the heights of the upper and lower canopies were measured. Mangrove abundance was counted in 9-25 m2 plots a t 3-9 m, intervals depending on the transect length. Maximum trunk diameters a t 1.5 m above ground were measured on large specimens. T h e general character of the substrate was noted. Frequency data herein is the percentage of sites at which the species were found. The scientific names of species follow Sterrer (1986) wherever possible. Specimens are deposited in the collections of the University of New Brunswick, and the experts mentioned in the acknowledgements assisted with identifications. The locations of the 33 mangrove swamps surveyed (Fig. 1) are listed together with their local names and areas along with the mangrove tree species present and whether the site is a coastal bay, Iagoon, anchialine pond, non-tidal pond or landlocked and non-aquatic (Table 1). The species found and their frequency of occurrence among the 33 swamps and summaries of the vertical zonation of dominant species in bay and lagoonal (marine) sites found growing above chart datum are given in Tables 2 and 3 respectively. Pond mangroves are not included in this table because the very variable, and often much reduced tidal regime among ponds makes direct correlation difficult. A composite vertical profile of all marine mangroves is shown in Fig. 2a, while Figs 2b and c show Ireland Island Lagoon [#1 Fig. 1, Table 11 and Riddels Bay [#9] as examples of the range of profiles surveyed. Profiles from three pond sites (Fig. 3) include a "mixed" mangrove at Evans Pond (3a)[#7], a red mangrove dominated situation at Mangrove Lake (3b)[#18], and the black mangrove dominated Lovers Lake (3c)[#28]. Profiles of two unique mangrove swamps are the mangrove-salt marsh complex at Mill's Creek [#I21 (Fig. 4a) and the "Great angrove" of Hungry Bay [#I61 (Fig. 4b). . Comparison o f mangrove swamps of Bermuda: mangrove tree species present, type of habitat and area occupied. Key to terms: R = Xlzizopt'~ot-ra marzgle; B = Aviccrzrzia gem.irznrls; B U = Corzocarpr~s erecteq Lagoon = marine with restricted connections with the sea; Pond = saline, non-tidal pond; An. Pond = anchialine (tidal) pond; Land = landlocked without pond. Site # Name Trees Type Area(m2) Ireland Island Head of the Scaur Somerset Long Bay Elys Harbour Pilchard Bay Whale Island Evans Pond Jew's Bay Riddels Bay Tom Wood's Bay Fairyland Creek Mill's Creek, Boss's Cove Lagoon Bay Pond Bay Bay Bay An. Pond Bay Bay Bay Bay Bay Paget Marsh Foot of Crow Lime Mangroville Hungry Bay Spittal Pond Mangrove L,ake Trotts Pond Compston Pond Shelly Bay Mangrove Cornmonland Walsingham Pond Walsingham Bay lue Hole Coney Island Tuckers Town Bay Lovers Lake Mangrove Bay Coot Pond Paget Island Pond Ferry Point U.S. Naval An Base Pond Bay Pond Bay Pond An. Pond An. Pond Pond An. Pond Land An. Pond Bay Ray Bay/Pondl Bay An. Pond Bay Bay Bay2 Bay Pond3 Mean 5310+6495 ' Former pond with channel cut to the sea. 2 Former bay, now divided by causeway. 3 Former bay, now a pond. Table 2. Check-list of plant and animal species and the percentage of localities at which they were collected in all Bermuda mangrove swamps. SPECIES - % SPECIES CYANOBACTERIA E~ztoplzysalis deusta 3 Scytorzerna hofmarzizii CWLOROP Acetabularia cre~zulura Amdyomene stellata Avrainvillea rzign'carzs B m d l t ' ~ p i s p~~.~i l la Ca ~rlerpa mexicaiia Craulerpu pclialu Cm~lerpu rcrcemosn Crarrlerpa serir~karioides Caulerpa verticillara Clzaetomorplza lilzum Akebia quinata Asparagzts plumosrrs Asparagl~s spreizgeri A vice~zrzia germirzaizs Bom'clzia arboresceizs Bomkhia frutescens Carpob rorrts clzilensis Casuariiza equisetifolia Perzicillus cnpitntus 3 Xl~ i zoc lo~z i~~m hookeri 3 3 4 6 Rlzizocloiai~~m r-43apiuw7 55 3 Udotea flabellunz 6 12 Valorziamacroplzysn 3 RHODOP 3 Ceramium n ~ h r u m 3 3 "Falkerzbergia lzilbebrandii" stage of 3 Aspa rragopsis 6 Halyme~zia he~mz~de~zsis 94 Lal~re~zcin oht~~slr 3 3 Wurdema~zrzin ininiara 3 EO A 3 MAGNOLIO 3 Nerium olemzder 9 Opurztia dillerzi Pittosponrm urzdulatum 73 Rlzizoplzorama~zgle 12 Ruppia man'tima 30 Sabal bemudnna 3 Saliconzia peremis 6 Schims tereb i~ztlzifolia 42 Ficus leiztigiizosa Foeniculum foerzicr~lum Halodnle bennudeixis Ipomoea sp. Eeucaeiza glauca ura ca veizdishii Acewoclzaliiza molitha Acewoclz aliiza cr-assilobrr Aplysilla loizgispiiza Biemna microstyla Clzoizdrilla izr~crda Ciiznclzyrella upioiz Desmascrda desdemoiza Dysiderr etlzen'a Ez~r~,poiz clavcrtum Geodia gih berosa Hymeizicrcidoiz ssp. Leucaizdra aspersa Aiptasia pnllida Bartlzolomea aiziznlata Areizicola cristata Spirorbidae Assimiizea succiizea Batillaria minima 6 Sesuvium portrdacastn~m 22 Syr-iizgodium filifonne 3 Tamarix gallica 3 Tamarix lzispida 6 Tlzalassia testudiizum Typlza aizgwtiJolia 3 Leucet fa iinherbis Lissodeizdoryx isodictyalis 3 Megalopastas izra 3 Mycale microsigmatosa 3 Niplzates erecta 5 Oceaizapin coela 3 Suberites ssp. Tedcr i zia igi zis Terpios aura iztiuca 3 Tetliya crctiizia 3 Ulosa n~etzleri 3 CNIDAR 9 Cassiopea xamaclzaiza 6 Palytlzoa maminilosa ANNELIDA 9 Sabellidae 9 MOLLUSCA 6 Eittoriiza aizgulifera 15 Melainpus coffezls Brnclzydoizres doiniizgerzsis Cerithiccin lutosuin Hyciro bin bennudne Isogizonzoiz nl~trls Lasnea ctdcrizsoizi Aim thin vidovici Bugc~la i~eriti iz~ Schizoporella scr-ialis Alpheus sp. Calliaizassa brmzileri Cnlliizecres sapidus Cnrdisoina gu~izlluini Clibaizarius tricolor Garrerncmzflzn sp. Gccnrcii ILLS lnter(11is C;oiziopsis cmeiz tla tcr Aplidium b e n n d n e Aplidiuin exile Borfylloides i l igmn Clnveliiza obloizgn Claveli~za picta Qstodyres delleclziajei Didemiz ~iin caizdidum Disrnplia bemudeizsis 3 Mitrelln ocellnra 15 Ovotelln myosotis 6 Pedipes miro bilis 6 Tnmcnrella cnribaeeizsis 4 ria subovoiden Zoobor/yoiz verticillntum 3 Ligi(tbnudirziarzn 3 Mithrnx forceps 3 Neplzilu clavipes 6 Pncllygropsus grncilis 4 Pnilopeus llerbsrii 30 Sesamn ricordi 9 Stenopus lzispidus 33 6 TUNICATA 3 Ecreiilnscidia coizkliizi 3 Ecreiizrascidin turbiizafa 3 Leprocliizuin macdoizuldi 3 Peropllora viridis 3 Plzallusia izigra 3 Polycitor capsulatus Styela plicafa 3 Aizolis gralzami Bufo marii~us Clzeloizin mydas CHORDATA 24 Eleutherodactylus jolzizstoizi 12 Malacleinys terryiiz 3 e m vertical zones above low-water level and their standard deviations: of the dominant plant species in Bermudian bay and lagoon mangrove swamps. Tidal heights a re in cIn above chart datum. Tidal Heights Species Part of plant Lower Limit Upper Limit Rlzizoplzora maizgle Rhizoplzora maizgle Rlzizoplzora maizgle Aviceimia germiizaizs Avicerzizia gemziizarzs A viceizizia gennirzaizs Coizocarpus erectus Conocarpus erectus Sclzimls terebintlzifolia Sclzims terebintlzifolin Bostryclzia moiztagnei Rlzizoclonium kenzeri Rlzizocloizium riparium Boniclzia frutescens Prop Roots Canopy1 Trunks1 Pneumat. Canopy' Trunks1 Canopy1 Trunks1 Canopy' Trunks' Entire Entire Entire Entire Sesuvium portulacastn~m Entire 'At sediment surface vertically below limit. For comparison, tidal levels are: Mean Low Tide Level 30 cm, Mean Tide Level 70 cm, Mean High Tide Level 105 cm and Extreme High Tide Level 150 cm. The average bay or lagoonal mangrove in Bermuda is about 25m wide, dominated intertidally by R. ~nar~glc and A. gemzinums, the former forming the seaward fringe and the latter the mid-portion of the community, but usually with considerable overlap. Above the high-tide mark, C. erectn and S. ~crz,hin~llifolia intermingle on rising drier ground. The height of the canopy top for these four species lies between 5 and 6 m. On prop-roots and pneumatophores in the lower to mid-intertidal, the red alga Bost~ychia mo~ztagmei Harvey is ubiquitous together with the green filamentous alga Rlzizocloizi~~m kenleri Stockmeyer, whereas R. riparitsm Harvey occurs in patches throughout the intertidal but not generally on the mangroves. Sesuvit~m port~~lacasm~rn L. is scattered above mean tidal level, giving way to an irregular band of Bon-iclzin fiz~rescerzs (L.) A. P. de Candolle around high tide mark. A wide variety of associated fauna and flora were found but none were regular and many were at a single location only (Table 2). The best developed and most diverse mangrove is at Hungry Bay on the south shore (Fig. 4a). This is the only Bermuda mangrove with a well developed drainage channel. The width of the swamp reaches 90 m, the canopy height exceeds 10 m in places, and their is no zonation among red and black mangroves, which are completely intermingled. The giant land crab, Cardisoma guailhumi Latreille, rare in Bermuda is common on the landward fringe, and the coffee-bean marsh snail, Melamptrs coffezls (L.), is found at only three locations, abundant in the upper intertidal. Trunk diameters of mangrove trees were largest here, with A. germimnils reaching 36 cm and R. mangle to 27 cm. The structure of pond mangroves (Fig. 3) differs considerably from that of bay mangroves. They are narrower, only 14.8 211.2 m wide compared to 30.6 520.1 for bay mangroves, but have a similar canopy height and are more varied. stands of either R. mamgle or A. genniizam, are typical (Table 2) in Bermuda ponds, but red and black mangroves are sympatric in Evans pond and Walsingham Pond. However, in Evans Pond, black mangroves dominate and red mangroves are scattered individuals except at the eastern end (see profile Fig. 3a). In the largest pond mangroves of Mangrove Lake and Trotts Pond, black mangroves are absent, as they are at the smaller Compston Pond and they are not abundant at Walsingham Pond. In contrast at Lovers Lake, red mangroves are absent. In the former pond (now connected to the sea) at Paget Island, red mangroves are confined to a few young trees at the seaward margin of the swamp, suggesting an earlier monospecific stand of A. gerrniiza~u. m a. BERMUDA AVERAGE MARINE MANGROVE PROFILE ................ ?Ah, b . IRELAND ISLAND B. rnontognei b 'd Red Mangrove seedlings A. crenulata ....... H. rnonile - - * - - - I I I 1 0 2 4 6 8 10 12 14 16m Figure 2. Profiles of Bermudian marine mangrove swamps: 2a, Profile for the average marine mangrove and key. 1 =Sclzirzns terebintlzifolia, 2= Coizocarpus erectus, 3=Aviceizizia gemiizans, 4=Rhizophora rnarzgle; 2b, Ireland Island Lagoon; and 2c, Riddells Bay. Species a re as in Table 2. MHW = Mean high water. MLW = Mean low water. T Red Mangrove seedlings 4 $* Syringodium --- c. LOVERS LAKE Figure 3. Profiles of Bermudian pond mangroves swamps: 3a, Evans Pond; 3b7 Mangrove Lake; and 3c7 Lovers Lake. Key and abbreviations as in Figure 2. a. HUNGRY BAY R . kerneri t P R.ripariurn 4 Red Mangrove seedl~ngs b 4 b C. Iinurn 4 B * I I I I I 1 I I i 0 4 8 12 16 20 24 28 32 36 4 Block Mangrove seedlings tb 4 Red Mangrove seedlings b Figure 4. Comparison of two profiles: 4a, Profile of the "Great Mangrove" at Hungry Bay; and 4b, Profile of a mangrove swamp-salt marsh complex at Mill's Creek. Key and abbreviations as in Fig. 2. About 150 species of macrobiota (Table 1) have been identified from the Bermuda mangroves but only a few species have wide distribution among the mangrove swamps. Seventy-three species (48.7%) were found at a single locality, while only 16 species (10.7%) occurred at 10 or more sites and only four species were present in over 50% of the mangroves. This unexplained discontinuity of distribution generally obscurs correlations with obvious physical environmental factors but, the pond mangroves tend to have unique assemblages of associated species. For example, B. montclpci, ubiquitous in the bay mangroves, occurs only in the mangrove ponds lsinghanl Pond and Lovers Lake. The mangrove oyster, Isngi~nunolz rrlrr~~~s melin)? and the sponges, Terpios mrtll acck Duchassaing Rt Chomirilla ~ L K L L ~ Q Schmidt, occur only in angrove Lake and Trotts Pond, the ascidian Styela pliclrfcr (Lesueur) only in Evans Pond, the holothurian 5ynnplr~ln hydrironnis (Lesueur) only in Evans Pond and Lovers Lake, and a host of species, including the endemic Scrrgcr.ccurn ~ C ~ ~ L L ~ C I C Grunow, is unique to YValsingham Pond. In a few locations, mangrove swamps adjoin small salt inarshes dominated by Sesuvium pormlactlstnun and/or Snliconlicl peremis Miller with associated Bnn-ichin clrboresce~zs (L.) A. P. de Candolle. At Mill Creek (Fig. 3b) the salt inarsh lies landward of the mangrove whereas at Foot of Crow Lane it fringes the mangrove to the seaward. The abundance of trees is highly variable among the swamps, the overall mean for 19. mmgle being 3842 +2415 ha.' and for A. gennimuts 2044 k2200 ha-'. The high standard deviations prevent any correlations with physical or biotic factors. D ON ay and lagoonal mangrove swamps in Bermuda, although they are smaller, are structurally and floristically similar to those of Florida (Davis 1940, Lugo and Snedaker 1975, Ball 1980), except that overall plant diversity is lower, a situation normal in oceanic islands where opportunities of immigration and colonisation are reduced (Mac Arthur and ilson 1967). Lot-Helgueras et (11. (1975) have described floristic characteristics of mangroves at their northern limit in the Gulf of Mexico, a situation comparable to Bermuda, except for latitude and the significant rainfall change within the transitional belt in Mexico. In the Gulf of Mexico, A. gennimns extends furthest north to 27.3"N, followed by C erectus to 25.7"N; 19. mmzgle and L. racemosa both stop at about 24"N, however, north of about 23"N, 19. mmgle trees are stunted and poorly developed; at this latitude the floristic composition of the swamp and tree size is similar to Bermuda, except that Batis maritima L., very common in the Gulf of Mexico, is absent in Bermuda. South of this latitude in the Gulf of Mexico the mangrove swamps have many more plant species than in Bermuda (Lot- Helgueras et (11. 1975). Monospecific stands of either A. genninans or R. ma~zgle are common in Bermudian pond mangroves at different locations (Table 1). All the Bermudian ponds are relatively close to the sea and the anchialine ones are very close, thus opportunities for colonisation via the sea may not differ greatly among the ponds. It might be expected that the smaller propagules of A. germiizaizs would be transported overland more readily than the larger ones of R. maizgle, however, several of the more inland swamps such as Mangroville, Paget Marsh and Compston Pond, are colonised by R. maitgle, while only one, Commonland Marsh supports A. germiiwizs. Three of the anchialine ponds have large connections to the sea through which propagules could pass. Of these, Lovers Lake has a monospecific black mangrove stand, Evans Pond supports a community strongly dominated by black mangroves, and Walsingham Pond is principally a red mangrove forest with a few black mangroves. There is no evidence that the presence of either species is related to tidal range or salinity. Both red and black mangroves appear to be equally capable of colonising marine ponds, however, once either alone is established, it appears to be able to occupy the entire zone colonised by both species in Bermudian bay mangroves, resulting in the essentially monospecific stands in inland mangroves. Even where the black mangrove has become established, either through man-made connections as in Paget Island, human introduction as in Evans Pond or natural processes as in nlsingham Pond, typical zonation never develops and the red mangrove characteristically exists as scattered trees or in small clumps. The times of colonisation of the Bermuda ponds by mangroves are not known, most were basically as they are now when the first settlers arrived (Lefroy 1884), however, Paget Island pond was connected to the sea about 1950 and red mangrove embryos were introduced into Evans pond in the 1970's (D. ingate pers. com.). In the latter case, it is likely that there were a few red mangroves present prior to the introduction since the examination of a few old trunks showed greatly in excess of 20 annual rings, however, a noticeable increase in red mangrove abundance has occurred near to the introduction site but not elsewhere. The high overall, but low site, total species diversity in the Bermudian mangroves is difficult to explain. Opportunities for colonisation in all but a few isolated inland stands appear not to differ greatly. It seems probable that environmental differences between sites may result in differential rates of settlement, mortality and growth. Some species may have had their distributions reduced by coastal pollution, since it is known that this has happened in the case of I. alntus, the mangrove oyster, formerly common in coastal mangroves (Sterrer 1986). There is no evidence of active succession in Bermudian mangroves most are remarkably stable, reductions being mainly attributable to man's activities. Sclziizr~s terebi~ztlzifolia, a fairly recent introduction is invading the drier, landward fringe of the mangroves. Ball (1980), in studying secondary succession, found long-term stability in Florida mangroves. In fact active succession in mangroves is mostly confined to areas of active sediment accretion ( e.g., Davis 1940, Chapman 1944, 1977). (1977) observation that there is such great variation in zonation patterns that they do not form a good model for succession, is borne out in the Bermudian mangroves. Mangrove tree abundances are very similar to those cited for Florida by Lugo and Snedaker (1975). ACKNOWLEDGEMENTS I am grateful to M. L. Harley for assistance in the field throughout the study, to Mr. T. McEachreon for help at Trotts Pond, to Ms. B. Blanchard who assisted at Lovers Lake and to Ms. K. Eakins at Walsingham Pond. Dr. J. Schwede of St. Petersburg, Florida, verified or identified many of the smaller algae collected, Dr. K. Ruetzler, Smithsonian Institution, Washington D.C. identified the sponge films. Dr. David Wingate, Bermuda Conservation Officer assisted with terrestrial plants and Dr. J. Winston of the American Museum of Natural History, New York identified Sclzizoporellu spp., to them I am most grateful. Financial assistance was provided by a Natural Sciences and Engineering Research Council of Canada operati@ grant and through a grant from the Canadian Associates of the Bermuda Biological Station for Research. The Bermuda Biological Station for Research and the Bermuda Aquarium, useum and Zoo provided laboratory facilities. Mrs. S. Rouja and Mrs. L. Marsland dly granted access to Evans Pond, Sir. H. Tucker to Mangrove Bay, the Riddells y Golf Club to Riddells Bay, the Mid Ocean Golf Club to Mangrove Lake, Trotts Pond and Cornpston Pond, and Mr. and . 23. 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