MARINE BIODIVERSITY IN FRENCH GUIANA: ESTUARINE, … · 302 gayana 67(2): 302-326, 2003 issn 0717-652x marine biodiversity in french guiana: estuarine, coastal, and shelf ecosystems

302

Gayana 67(2): 302-326, 2003 ISSN 0717-652X

MARINE BIODIVERSITY IN FRENCH GUIANA: ESTUARINE, COASTAL, ANDSHELF ECOSYSTEMS UNDER THE INFLUENCE OF AMAZONIAN WATERS

LA BIODIVERSIDAD MARINA EN GUYANA FRANCESA: LOS ECOSISTEMASDE ESTUARIOS, LAS COSTAS Y PLATAFORMAS BAJO LA INFLUENCIA DE

LAS AGUAS AMAZONICAS

Luis Felipe Artigas1, Philippe Vendeville2, Marc Leopold2, Daniel Guiral3

& Jean-François Ternon3

1L.A.B.E.L. (UMR 8013 ELICO) - Université du Littoral Côte d’Opale - M.R.E.N. - 32, av. Foch – 62 930Wimereux – France. Email: [email protected]

2Institut Français de Recherche pour l’Exploitation de la MER – IFREMER Délégation Guyane – Domaine de Suzini– BP 477 – 97 331 Cayenne - French Guiana

3L.E.L. (UR R053 ELISA) – Institut de Recherche pour le Développement – IRD Centre de Cayenne – route deMontabo – BP 165 – 97 323 Cayenne Cedex – French Guiana

ABSTRACT

Marine biodiversity in French Guiana is strongly influenced by the amagon River waters of the river Amazon, which constitute amajor structuring factor for the estuarine, coastal, and shelf marine ecosystems. Moreover, the marked seasonal and interannualvariabilities play important roles in the stability or fluctuations in the environmental parameters that influence biodiversity at theecological, population, and genetic levels. Previous and ongoing studies of the marine and littoral biota relate mostly to commercialmarine species, protected species in danger of extinction and, specially, to the biodiversity and functioning of local coastal andlittoral ecosystems such as estuaries, mudflats, sandy beaches and, particularly, littoral mangroves. A more integrated approachinvolving local, regional, and international scientific collaboration is needed for a better assessment and understanding of marinebiodiversity. Such studies would benefit from international cooperation that would allow the gathering of new information and thecomparison of previous data, the organization of common oceanographic surveys, the homogenisation of analytical protocols, andalso favour the exchange of scientists and postgraduate students for a real transfer of ideas, techniques, and know-how. Moreover,research on the comparative biodiversity of analogous littoral and marine ecosystems in different parts of South America wouldallow a more accurate estimate of marine biodiversity on a continental scale.

KEYWORDS: French Guiana, marine biodiversity, coastal systems, Amazon river waters, Intertropical Convergence Zone,ecological and conservation studies

RESUMEN

La biodiversidad marina en la Guyana Francesa está fuertemente influenciada por los aportes amazónicos, los cuales constituyenun factor estructurante de los ecosistemas estuarianos, costeros y de plataforma continental. Además, debido a las cambiantescondiciones meteorológicas y oceanográficas, la variabilidad estacional e inter-anual puede jugar un rol importante en la estabilidado la modificación de los parámetros medio-ambientales que afectarían la biodiversidad ecológica, poblacional y genética de losecosistemas locales. Los estudios llevados a cabo sobre la biología de las especies marinas y litorales se refieren principalmente aespecies de interés comercial, especies protegidas en peligro de extinción, y sobre todo a las características del funcionamiento deciertos ecosistemas costeros y litorales característicos como los estuarios, bancos de fango, playas de arena, y sobre todo losmanglares. La idea de estudios o series de estudios mejor coordinados entre sí a nivel regional e internacional, emerge como unanecesidad para una mejor estimación y comprensión de la biodiversidad marina. Estos estudios beneficiarían de una importantecooperación internacional que pemitiese comparar e integrar el conjunto de datos obtenidos en el pasado, llevar a cabo misionesoceanográficas conjuntas, mutualizar y homogeneizar los protocolos analíticos, y favorecer el intercambio de técnicas y estrategiaspor intermedio de intercambios de científicos y estudiantes en formación de postgrado. Finalmente, estudios comparativos sobre labiodiversidad de sistemas costeros análogos sudamericanos permitirían de alcanzar una mejor estimación de la biodiversidadmarina de este continente.

PALABRAS CLAVES: Guayana Francesa, biodiversidad marina, sistemas costeros, aportes de aguas Amazónicas, Zona Intertropical deConvergencia, estudios ecológicos y de conservación.

Simposio.p65 05-04-04, 11:12 a.m.302

303

Gayana 67(2), 2003

INTRODUCTION

Until recently, most of the marine researchprograms developed in French Guiana dealt withsedimentology and geomorphology (e.g.Moguedet 1977, Bouysse et al. 1977, Prost 1989,Pujos & Froidefond 1995) or fisheries (e.g. Bullis/Thompson 1959 ; Morice Warluzel 1968 , Abbeset al. 1972, Bonnet et al. 1975, Venaille, 1979,Dintheer et al. 1989a, Blanchard et al. 2000 ; Rivotet al. 2000). In 1997, however, the first integratedprogram (PNEC: National Program of CoastalEnvironment) supporting coastal oceanographicresearch in French Guiana (Fig. 1) was set up withthe participation of several French research insti-tutes and universities (Clavier 1996). Thisprogram focuses mainly on the characterizationand quantification of the influence of the Amazonriver on the continental shelf and littoral zone ofFrench Guiana, in terms of coastal oceanography(physical and bioge-ochemical characteristics inrelation to living resources), geomorphology(mudflat displa-cements along the coastline), andmangrove ecosystems (particularly thosecolonizing the stabilized mudflats). The ultimateobjectives of the PNEC program are to establisha better monitoring system of economicallyexploited living resources (fishes and shrimps)as well as improve economical management andecosystem preservation of the coast where about90% of the population of French Guiana live.At present, in addition to fisheries studies andfish and shrimp stock assessments carried out asparts of the IFREMER programs, ongoing ma-rine research is concerned with 4 different spa-tial scales: 1) the continental shelf (the ‘‘CHI-CO’’and ‘‘GREEN’’ oceanographic projects -PNEC), 2) the littoral the ‘‘ELISA’’ coastal (0-20 m depth) project of the IRD, the PNECprogram, and the Cayenne Island ‘‘LITEAU’’program 3) estuaries (e.g: the Kaw River estuary-PNEC and ELISA-IRD, programs), 4) islands(Grand Connétable Island Natural Reserve).Three complementary strategies are beingemployed: 1) observations and measurements onvarious spatial scales (continental shelf, mudflats,estuaries), 2) the development of a hydrodynamicnumerical model for the continental shelf andcoastal zone, and 3) the analysis of satellite data.The nutritional requirements of certain targeted

marine species have also been investigated aswell as the biological colonisation of the mudflats.As well as this large scale institutional approach,local naturalist and ecological associations areinvolved with more specific studies (e.g. marineturtles). This paper reviews, firstly, our presentknowledge of the structure of the marine, coastal,and littoral ecosystems, in order to assess localand regional marine biodiversity in FrenchGuiana, and then discusses possible perspectiveson short and medium term bases.

CLIMATIC AND OCEANOGRAPHIC CONDITIONS

French Guiana has a typical wet equatorialclimate, driven mainly by the seasonal meridionalmigration of the Intertropical Convergence Zone(ITCZ). In its southern position, the ITZC cau-ses northeast trade winds in French Guiana fromJanuary to July while, for the rest of the yearwhen it is in its northern situation, the countryexperiences southeast trade winds. There are 2periods of high rainfall, May - June (the princi-pal one) and January- February (secondary). Thedry season lasts from July to December when sta-ble south-eastern trade winds are dominant. Theflow of the rivers of French Guiana is similar tothat of the rainfall being maximum in May-Juneand minimum generally in November, when theflow rate of the Amazon River is considerablylower. The tide in French Guiana is semidiurnal,with an amplitude of up to 2.5 meters (springtides, mesotidal regime). With its 320 km ofcoastline from the Oyapock estuary in the eastto the Maroni estuary in the west, French Guianais included in the Amazon-Guianas ecotone thatextends from the Amazon River mouth to theOrinoco River mouth and is considered to be partof the “Guianas Coastal Province” (Longhurst1998). The coastal waters of this province arehighly turbid, specially north of the Amazonmouth, and extensive mudflats occur and migratealong the coast (Froidefond et al. 1988). Indeed,from January until July, the meso-scale coastalcurrent (North Brazil Current, NBC) and its ex-tension, the Guianas Current (GC), flow north-westwards, carrying the low-salinity and nutrient-and sediment-rich water coming from theAmazon along the sorelines of French Guiana,Suriname, Guyana and Venezuela (Fig. 2). During

Simposio.p65 05-04-04, 11:12 a.m.303

304

Gayana 67(2), 2003

the period of NBC retroflection, more saline andless turbid surface waters cover most of the con-tinental shelf. These 2 well differentiatedhydroclimatic situations, together with a markedspatial and temporal variability, representmajor constraints for the coastal ecosystemsand their biota. Moreover, constant upwelling,that is not accompanied by a pronounced

lowering of the sea surface temperature butprovides additional nutrient enrichment, wouldle generated by the direction of the prevailingwind and the geos t rophic s lope of thei sopycna ls assoc ia ted wi th the GuianasCurrent, which is enhanced by the outflowingAmazon water (Cadée 1975).The “SABORD 0” cruise in May 1996 was the first

FIGURE 1. French Guiana Coastal and Shelf areas (from Frouin 1997). Protected areas are shown in rectangles.

FIGURA 1. Areas costeras y de plataformas en Guyana Francesa (Frouin 1997). Las áreas en rectángulos son protegidas.

Simposio.p65 05-04-04, 11:12 a.m.304

305

devoted to the French Guiana continental shelf. Asteep salinity gradient found at about 10 m depthshowed the presence of a low salinity surface layer.Geochemical measurements made on the surfacewater showed that it was of Amazonian origin (lowsalinity / high silicate / low CO

2). The area acts as a

sink for atmospheric CO2, unlike the equatorial ocean

which is generally considered to be a global sourceof CO

2 (Ternon et al. 2000). The “CHICO” project,

which started in 1999 within the framework of the“PNEC” program, consists of physical and bio-geochemical oceanographic cruises over the wholecontinental shelf during 3 periods with differentcharacteristics: February (the start of the wet season;no NBC retroflection; increase in the Amazon flow),May (the wet season; start of NBC retroflection;maximum Amazon flux), and November (the dryseason; NBC retroflection; minimum Amazon flux).Physical, chemical and biogeochemical parametersare being determined from the coast (20 m depth)out to the shelf break (200 m depth), on an east towest transect across the continental shelf. At thesame time, cruises for fish and invertebrate speciesbiology (‘‘GREEN’’) are conducted over the samearea. A numerical model of the dynamics over the

shelf is currently being developed (C. Chevalier, IRD-Marseille) and will eventually be linked to abiological model (M. Baklouti, IRD-Marseille). Thepreliminary “CHICO 0” cruise confirmed (Ternonet al. 2001, 2002) that the hydrodynamics of theFrench Guiana continental shelf present remarkablefeatures caused by the presence of a large area oflow salinity water at the surface (8 to 10 m depth),mainly from the Amazon, over most of the shelf(out to 120 km from the coast). Four water classeswere identified using radiometric measurements atwavelengths corresponding to those of the SeaWIFSsensors and could thus represent water masses ofwell differentiated biogeochemical characteristics(Froidefond et al. 2002).

THE HISTORY OF BIOLOGICAL OCEANOGRAPHY IN FRENCH

GUIANA

Knowledge about the marine resources of FrenchGuiana followed the development of fishingactivities over the continental shelf and slope(Frouin 1997, Bernadac et al. 1999). The firststudies occurred after the second world war, at

FIGURE 2. Surface circulation in the tropical Atlantic Ocean (from Johns et al. 1998, in Ternon et al. 2002).

FIGURA 2. La circulación superficial en el Oceáno Atlántico tropical (Johns et al. 1998, en Ternon et al. 2002).

Marine biodiersity in French Guiana: ARTIGAS, L. ET AL.

Simposio.p65 05-04-04, 11:12 a.m.305

306

Gayana 67(2), 2003

the end of the 1940s, with the compilation of aninventory of marine fish species from artisanalcoastal fishery landings (Puyo 1949). During the1950s, when the American shrimp fisheries in theGulf of Mexico extended to Central America andthen to north South America, trawling surveyswith R.V. Oregon covered both the northernBrazil and Guianas areas and were concernedmainly with shrimp species, but included theassociated fish species. Between 1954 and 1958,ORSTOM (IRD) scientists studied the benthicand demersal continental shelf fauna between 15and 100 m depths (Durand 1955, 1959). Later,during the 1960s and 1970s, ships from the USA,Japan, Korea, Venezuela, and Cuba operated offthe Guianas and northern Brazil for shrimp andred snapper fisheries (Venaille 1979) and this ledto an improvement in the knowledge of thedemersal and benthic fauna. The local ISTPMlaboratory, founded in 1971 (IFREMER), carriedout trawling surveys between 20 and 1000 mdepths with the R.V. Thalassa (Abbes et al. 1972),the R.V. Phaeton (1975) and the Deana T (1976-1978). It also participated in scientific cruisesorganised by other countries (Dragovich et al.1978), Kaiyo Maru in 1973 (Japan) and OregonII from 1972-1976 (NMFS-USA), and, in 1975,carried out its own trawling in the littoral areabetween 5 and 15 m depths, focusing on seabob,a coastal penaeid shrimp (Bonnet et al. 1975).The first primary productivity measurements(CICAR Dutch cruises) in both the Suriname andFrench Guiana shelf zones were also made duringthis period (Cadée 1975).Surveys during a Japan Marine Fishery ResourceResearch Center (JAMARC) program conductedoff Suriname and French Guiana from 1979 to1983 resulted in the identification of 452 speciesof bottom fish, 146 species of crustaceans, and143 species of molluscs trawled in the area from10 to 1000 m depth (Aizawa et al. 1983, Takedaand Okutani 1983). This survey program alsoincluded an analysis of the shrimp species caughtincidentally and a resource assessment(Vendeville 1984).The IFREMER PENJU (1987-88) and ORSTOMJUVECREV (1989-90) trawling surveys bothfocused on the spatio-temporal distributions ofshrimps (Dintheer & Rosé 1989, Vendeville &Lhomme 1997). In the same periods, IFREMER

conducted surveys of red snapper populations(Perodou 1994, Rivot 2000; Rivot et al. 2000).Similar surveys (IFREMER RESUBGUY) in1993-94 updated incidental shrimp catchassessment in the 15 to 60 m depth area in terms ofcommunities and assemblages as well as providingfurther spatial distribution information (Guéguen1993a, b, Nérini 1994, Rosé 1994, Rosé & Achoun1994, Moguedet et al. 1995).In 1994, another trawling survey (the EPAULARDcruise) was carried out in the littoral area from thecoast out to 15 m depth and focused on shrimp andjuvenile fish population distribution (Vendeville1995) and, in 1999, a preliminary survey (GREEN0 cruise, PNEC project) was made.Research in the infralittoral area began in 1971 withthe study of a coastal marsh in the western part ofFrench Guiana and the biology of the young stagesof the shrimp Penaeus subtilis; this was in relationto the ORSTOM (IRD) project for the developmentof shrimp aquaculture in the country (Rossignol1970, 1972a, b, c). After the introduction of ricecultivation in the area in 1984, a short study wasconducted by ORSTOM and IFREMER to evaluateits impact on marine resources (Lointier & Prost1986, Dintheer et al. 1985). Between 1988 and mid1994, numerous data and observations on the youngstages of shrimps (postlarvae and juveniles ofPenaeus subtilis, Xiphopenaeus kroyeri andMacrobrachyum sp.), in relation to the variabilityof shrimp recruitment in the fishery, were collectedin several estuaries (Vendeville & Lhomme 1997).

FISHERIES IN FRENCH GUIANA

The continental shelf shrimp fishery in FrenchGuiana started to develop with the arrival of UStrawlers at the end of the 1950s and Japanese fishingboats a few years later. The fishing fleet was largestin 1983 and then declined steeply until 1991.Nowadays, the shrimp fleet is exclusively Frenchand has 63 trawlers. With the departure of theforeign fishing companies, shrimp production wasdirected to the European market where smallershrimps were commercially acceptable, and thefishing activity tended to move into shallowerareas (Moguedet et al. 1995, Béné 1996, Charuauet al. 2000). The two main species beingexploited are Penaeus subtilis (the brown shrimp)and Penaeus brasiliensis (the pink spotted

Simposio.p65 05-04-04, 11:12 a.m.306

307

shrimp), but Penaeus schmitti (the white shrimp)and Penaeus notialis (the pink shrimp) are alsoencountered in mixed catches from the area. Thecoastal shrimp Xyphopenaeus kroyeri (the sea-bob)is sometimes kept as a bycatch product for the lo-cal market. The maximum shrimp landings occurbetween February and June. Since 1999, however,the fishery has markedly declined, productionfalling by 30% from 1998 to 2000 (IEDOM 2001).The same decrease has been observed in theneighbouring countries and is, in part, linked tounfavourable hydroclimatic conditions affectingrecruitment (Charuau in FAO/WECAFC 2001a,2001b, 2002, Dintheer Kalaydjian 2002).The continental slope shrimp fishery started in 1988.It is seasonal and very small (2 to 4 boats) andconcerns 2 species: Plesiopenaeus edwardsinus (thescarlet prawn) and Solenocera acuminata (theorange shrimp) (Guegen 1991 a, b). Landings havebeen decreasing since 1988.The second significant continental shelf fishery isthat of the red snapper (Lutjanus purpureus). Otherspecies (Rhomboplites aurorubens and Lutjanussynagris) are also found but less commerciallyexploited. This fishery is mainly practiced byVenezuelan long line trawlers.About 30 species are commonly exploited by thesmall scale coastal fishery. The principal types areweakfishes (Cynoscion acoupa, C. virescens,Plagioscion squamosissimus), sharks (Syphyrnaspp., Carcharinus spp.), sea catfishes (Arius proopsand A. parkeri), Tripletail (Lobotes surinamensis),snooks (Centropomus spp.), Tarpon (Megalopsatlanticus), mullets (Mugil spp.), Crevalle Jack(Caranx hippos), stingrays (Dasyatis guttata), andGiant grouper (Epinephelus itajara).

MARINE MACROFAUNAL POPULATIONSDEMERSAL AND BENTHIC CONTINENTAL SLOPE ORGANISMS

Of the 40 Decapod (Crustacea) species observedduring 4 surveys conducted over the continentalslope between 200 and 900 m depth from August1990 to July 1991, 2 deep-water shrimps have beenthe target of the industrial fishery since 1988: theorange shrimp Solenocera acuminata (Soleno-ceridae) and the scarlet prawn Plesiopenaeusedwardsianus (Aristeidae). The shrimp A.antillensis was also widely distributed in the muddy

sediments of the deep slope from 456 to 818 m depth(Guéguen 1991 a, b, 2001). In earlier trawling surveys(JAMARC; 1979-83) on the Suriname and FrenchGuiana continental slopes, 68 species of Decapodand 63 of Molluscs were identified (Takeda &Okutani 1983).

DEMERSAL A N D BENTHIC CONTINENTAL SHELF

ORGANISMS

Four studies based on trawling surveys on thecontinental shelf concerned the demersal andsometimes the benthic macrofauna:· In the first detailed study of demersal and benthiccontinental shelf macrofauna, Durand (1959)identified 21 Echinoderm species, 38 Crustaceans,34 Molluscs, and 133 Osteichtyan species. Fromthe analysis of the 400 stations sampled, theauthor concluded that there was a strong linkbetween the fauna, the depth, and the substratumquality.· An analysis of the 4 Japanese surveys conduc-ted on the continental shelf of French Guiana,based on 144 sampling stations and using 143taxonomic references, pointed out thepredominant role of the depth and, secondarily,the nature of the sediment cover, in determiningthe composition of the demersal assemblages(Vendeville 1984).· The results of the 1993-94 RESUBGUY surveysconfirmed the roles of depth and substratum indetermining the fish and invertebrate biodiversitybetween 20 and 60 m depths (Nérini, 1994;Moguedet et al. 1995; Guéguen 2000). The resultsrevealed 3 distinct faunal assemblages: 1) a littoral(or shallow-water) community present from 0 to30 m depth in coastal brackish waters of salinities< 25‰ characterized by muddy bottoms; 2) amiddle-shelf community distributed from 30 to 50m depth in turbid marine waters characterized bymuddy bottoms; and 3) a lower-shelf communityin deeper marine waters of low turbidity (depths> 50 m) characterized by sandy bottoms withoccasional rocks. In an attempt to simplify thisdistribution pattern, Moguedet et al (1995)proposed to distinguish between only 2 majortypes of demersal communities, coastal and deep-sea (Table I) . Most of the 110 differentmacrobenthic species observed in that study hadalready been encountered in the 1980-81 Japa-nese


Simposio.p65 05-04-04, 11:12 a.m.307

308

Gayana 67(2), 2003

surveys, including 8 Decapod Crustaceans (5Penaeidae, one Palinuridae, one Portunidae and oneCalappidae), 2 Cephalopods (one Loliginidae andone Octopodidae), one sea turtle (Cheloniidae), and99 demersal fish, mainly 9 Sciaenidae, 5 Ariidae, 5Serranidae, 4 Lutjanidae, 6 Carangidae, and 9Pomadasyidae. Despite the high species richnessof the benthic and demersal macrofauna, mostspecies showed a low count, and only 12 of them

comprised more than 80 % of the total capturesobtained from 0 to 60 m depth: Dasyatis america-na, Orthopristis ruber, Macrodon ancylodon,Stellifer rastrifer, Upeneus parvus, Ariusgrandicassis, Arius rugispinis, Lutjanus synagris,Chloroscombrus chrysurus, Cynoscion simileis,Gymnura micrura and Xiphopenaeus kroyeri.The most recent study carried out on themacrofauna was the preliminary survey cruise,

TABLE I. Summary of the specific composition of the principal demersal communities on the French Guiana continentalshelf (from Moguédet et al. 1995 and Frouin 1997).

TABLA I. Resumen de la composición específica de las comunidades demersales principales en la plataforma conti-nental de Guyana francesa (de Moguédet et al. 1995 y Frouin 1997).

Demersal communities Families Species

Coastal 0 – 30 m depth Sciaenidae Cynoscion virescens, Nebris microps,

Macrodon ancylodon, Stellifer rastrifer

Ariidae Bagre bagre, Arius parkeri, Arius rugipinis

Batrachoididae Batracoides surinamensis

Clupeidae

Dasyatidae Dasyatis americana

Penaeidae Xyphopenaeus kroyeri, Penaeus subtilis

Gimnuridae Gimnura micrura

Sciaenidae

25 – 30 m depth Penaeidae Penaeus subtilis

Pomadasyidae Genyatremus luteus, Pomadasys corvinaeformis

Engraulidae Anchoa spinifer, Anchoviella lepidentostole

Deep sea 30 – 60 m depth Lutjanidae Lutjanus purpureus, Lutjanus synagris

Gerreidae Eucinostomus argenteus

Carangidae Chloroscombus chrysurus, Selene vomer

Pomadasyidae Orthopristis ruber

Bothidae Syacium papillosum

Mullidae Upeneus parvus

Simposio.p65 05-04-04, 11:12 a.m.308

309

GREEN 0, realised in April 1999. The role ofbathymetry as the principal structuring factor of thebenthic and demersal ecosystem, already identifiedin previous studies as mentioned above, wasconfirmed and defined by the observations madeduring the GREEN 0 cruise (Le Loeuff & Von Cosel2000; Vendeville et al. 2000, 2002), which took placein the middle of the wet season and the period ofmaximum discharge of both the local estuaries andthe Amazon River. The importance of the nature ofthe substrate was pointed out and the nychtemeralrhythm was also defined as a structuring factor. Thesalinity gradient probably does not have a directinfluence on the spatial distribution of the benthicand demersal populations because the low salinityis localised in the upper layer.During the CHICO 0 cruise, an inorganic nutrientlayer was observed near the sea bottom, whereshrimps were abundant. This may in part beexplained by the remineralisation by heterotrophicbacteria of the organic matter arriving on the bottomas waste from shrimp fishing. As many as 107benthic species (Cnidaria, Polychaeta, Crustacea,Mollusca, and Echinodermata) were then identified,as well as 139 demersal species belonging to 3zoological groups (Cephalopods, Chondrichtyans,and Osteichtyans). An analysis of the specificrichness and abundance of these communitiesshowed that only a few species in shallow sea-bedsare characterized by high abundances, whereasnumerous species identified in the deep sea-bottomsare characterized by weak abundances. Four typesof communities were distinguished, 3 of them beingassociated with the principal regional Penaeidshrimps: 1) Deep communities of the ‘‘clear wa-ters’’ at 55 to 85 m depths, in mid and coarse-grainsands and coral reefs: shrimps (Penaeusbrasiliensis), soles (Gymnachirus nudus), coral reeffishes, red snappers (Lutjanus purpureus), andgrunts (Orthopristis rubber); 2) Mid-depth (55 –65 m) communities, in fine-grain sands and rocks:lane snappers (Lutjanus synagris), grunts(Orthopristis ruber) and searobins (Prionotuspunctatus); 3) Mid-shelf (45 – 55 m) communities,in muddy sands of fine and very fine grains: shrimps(Penaeus subtilis), some Sciaenidae (Micro-pogonias furnieri, Stellifer rastrifer, Cynoscion si-milis); 4) Littoral communities of ‘‘turbid waters’’at 15 to 35 m depths, of mud and muddy sands:‘‘seabob shrimp’’ (Xiphopenaeus kroyeri), Ariidae

(Arius grandicassis, Bagre bagre), with increasingnumbers of Sciaenidae (Cynoscion virescens,Macrodon ancylodon, Paralonchurus elegans,P.brasiliensis ), and Dasyatidae (Dasyatisamericana). While the nature of the sediment layeris the principal structuring factor of the benthic anddemersal communities of the French Guiana conti-nental shelf, in shallow regions, the brackish coastalwater has a great influence on the littoralcommunities. In the latter ecosystem, nychtemeralrhythms would be the third structuring factor.Therefore, the principal causes of the temporalvariability of fishery resources have to be definedin terms of the strict spacial limits of this ecosystem.Definitely, 3 adjacent ecosystems seem to interactin controlling nutrient inputs and the biologicalcycle, and determining the productivity of thesystem: the continental shelf, the littoral zone, andthe local rivers.

DEMERSAL AND BENTHIC LITTORAL ORGANISMS

During the 1994 li t toral trawling survey,“Epaulard”, carried out between the coast and15 m depth, 52 species were observed in thecatches at the 81 stations sampled: 8 Crustaceans,including 5 shrimps, two Penaeidae (Penaeussubtil is and Xiphopenaeus kroyeri), onePalaemonidae (Nematopalaemon schmitti);sometimes very abundant), one Hippolytidae(Exhippolysmata oplophoroides) and oneSergestidae (Acetes sp.), two crabs, and one sto-matopod.Molluscs were represented by only one gastro-pod, Bursa bufo.Three species represented Batoid fish, two spe-cies of Dasyatidae and one of the Gymnuridae.Among the 40 bone fish species encountered, themain families were Ariidae (7 species), Sciae-nidae (9 species), and Carangidae (5 species).Most of the catches concerned young individu-als. AFC and CAH analysis showed that bottomquality and hydrology (temperature and salinity)were structuring factors of these communitiesand, in particular, the role of Guianese riverplumes in the distribution of these species(Vendeville 1995; Vendeville & Lhomme 1997).Most of the knowledge on coastal fish diversitycomes from a study on small scale fishery landings(Blanchard et al. 2000).


Simposio.p65 05-04-04, 11:12 a.m.309

310

Gayana 67(2), 2003

FISH AND INVERTEBRATES IN THE INFRALITTORAL AREA

(COASTAL MARSHES AND ESTUARIES)

In 1971-72, preliminary investigations wereconducted in a western coastal marsh near Mana inorder to introduce brown shrimp (Penaeus subtilis)aquaculture. Biological data were collected on thejuveniles and postlarvae of the brown shrimp andaquatic fauna (Rossignol 1972c). A later study byIFREMER in 1985 concerned mostly the brownshrimp (Dintheer 1986). A brief study in 1994discovered that the marsh had evolved and that itsfunction as a shrimp nursery had been greatlyreduced (Le Cour Grandmaison 1995). Thepresence of predators of the brown shrimp(Mugilidae, Tarpon atlanticus, and Centropomusundicimalis) and of some juvenile fish (Achirusachirus, Batrachoides surinamensis, and Hemi-gramus ocelifer) was noted.A study of the life-cycle, recruitment, and youngstages of the brown shrimp was carried out from1988 to 1994. Bi-monthly samples were collectedin several estuaries in order to assess the seasonaland interannual variations in its postlarval andjuvenile abundances. The postlarvae entered theestuaries on the flood tide and left on the ebb tide.The recruitment of postlarvae occurred all the yearround on the French Guyana coast with between 2and 4 intensive periods, and it was concentratedmore in the western area. Data on other shrimp andprawn species were also collected (Xiphopenaeuskroyeri, Nematopalaemon schmitti, Acetes sp., andMacrobrachium sp.).The Kaw estuary was also sampled, betweenAugust 2000 and July 2001, for brown shrimptogether with its associated fish community(Vendeville 2002). The sampling showed 3seasonal peaks of brown shrimp postlarvalabundance: in September, a weaker one inDecember with the third, also weaker, inFebruary-March. These periods of abundancecoincided with those which had been observedin other estuaries (Vendeville & Lhomme 1997).The transport of the postlarvae during a tidalcycle, as characterized in other estuaries, wasalso observed in the Kaw River estuary andextended to juvenile fish coming from the coastalzone.

A REVIEW OF MARINE ICHTHYOLOGICAL DIVERSITY IN

FRENCH GUIANA

Marine fish species are not systematically stud-ied in French Guiana and it is difficult to quan-tify fluctuations in the populations. IFREMER(Cayenne) focused its studies mainly on the ex-ploited fish (targeted species and incidentalcatches). Species associated with rocky substratesremain badly identified, as are pelagic speciesand the small benthic species of the littoral. Inparticular, some uncertainties persist with regardto certain families such as the Scianidae(Plagioscion genera), Mugilidae, Serranidae,Engraulidae, Clupeidae, and Gobiidae.The data available on the ichthyological faunacomes from various sources, not all published,and are enriched by information gathered duringscientific surveys conducted by French and for-eign institutions throughout the 20th century (seeearlier paragraph on the history of biologicaloceanography in French Guiana). Fourmanoir(1971) provided the fi rst record ofCarcharhinidae species in French Guiana waters.The atlases of the freshwater fish of FrenchGuiana published by the MNHN (Paris) (Keithet al. 2000; Le Bail et al. 2000, Planquette et al.1996), and some INRA publications (Le Bail etal. 1984a, b, Rojas-Beltran 1984, Boujard & Rojas-Beltrán 1988) allow an approximate estimation ofthe number of brackish water fish species foundin the littoral to be made. Information is at presentbeing compiled by M. Léopold (IFREMER) onfishes of the Guiana continental shelf. This listcould be updated and supplemented in the nextfew years if the project of the Ichthyological In-ventory of French Guiana led by the MNHN (Paris)materializes, and also if the planned GREENcruises (PNEC program) take place.A 2 nautical mile margin around the ConnétableIslands (4°51’N, 51°26’W) to protect the birdpopulation constitutes the only real marine re-serve of French Guiana. These small islands arecolonized by a large community of sea birds (frig-ates, sterns, noddis, and gulls) that feed on cer-tain fish species. No study has yet been made ofits marine fauna but a survey could take placesoon of the numbers of the giant grouper,Epinephelus itajara, there.

Simposio.p65 05-04-04, 11:12 a.m.310

311

PLANKTONIC BIODIVERSITY IN COASTALWATERS

THE ECOLOGY OF THE MICROPLANKTON IN COASTAL AND

ESTUARINE WATERS

The coastal waters of French Guiana are subject tolarge inputs of dissolved and particulate matter fromthe Amazon River, from the local hydrological sys-tem, and also from the extensive mudflats byresuspension processes (Froidefond et al. 1988). Ofthese, the Kaw River carries most of the drainagefrom the Kaw swamp. Near the littoral mudflats,the high levels of suspended particulate matter limitlight penetration, modify the N/P mineral balancedue to the adsorption of phosphate (Guiral &Plenecassagne 2002) and reduce phytoplanktongrowth (DeMaster et al. 1991). A zone of high chlo-rophyll and primary production has been observedoutside the turbid coastal waters on the continentalshelf (Cadée 1975, Ternon et al. 2001, 2002). Artigas& Guiral (2001, 2002) carried out a comparativestudy of the phytoplankton and bacterial biomassespresent during 2 extreme seasonal conditions. Atthe end of the wet season (July 2000), the high lev-els of degraded pigments in the riverine and transi-tional zones suggested the presence of large amountsof allochtonous matter from the flooded lands andthe Kaw swamp, and forest marshes and wetlands.The would have been in an advanced state of degra-dation and thus stimulated bacterial production lead-ing to large numbers of these microorganisms asso-ciated with the very low chlorophyll a concentra-tions. Transport from the mudflats and young man-groves seems to contribute to the high pigment con-centrations measured, in July 2000, in the mudflatlittoral waters. The resuspension of benthic diatomsand/or their grazing by benthic organisms mightexplain the prevalence of large forms and degradedpigments. In November, mean total estuarine chlo-rophyll concentrations were up to 10 times higherthan in July, and were correlated, along the estua-rine gradient, with bacterial abundances. The high-est photosynthetic rates in coastal waters were ob-served in November, probably due to the combina-tion of senescence and the grazing of a largephytoplankton bloom enhancing and diversifying thepathways of organic matter transfer betweenphotoautotrophs and heterotrophic bacteria. Newstudies of phytoplankton species cycles and their

productivity and competition with heterotrophicbacteria for nutrients are in progress.

THE BIODIVERSITY OF THE PHYTOPLANKTON IN THE

MARINE AND BRACKISH WATERS OF FRENCH GUIANA

Only a few surveys of the phytoplankton specieshave been made. The first data for the area camefrom the adjacent zones (Teixeira & Tundisi 1967;Margalef & González-Bernáldez 1969) and, onlylater, from 1976 to 1979, were the microplanktonof local marine and brackish waters studied(Paulmier 1993).Skeletonema tropicum was prevalent in the estuarinezone with Chaetoceros subtilis var. abnormis,Dytilum sol, Thalassionema nitzchioides,Coscinodiscus jonesianus, C. aculeatus, C. oculus-iridis, C. curvatulus, and Odontella mobiliensis alsopresent. Resuspended benthic diatoms (pennateforms) and thycopelagic (centric and pennate) formstogether with sessile or pedonculata types werecharacteristic of the estuarine waters. The mostrepresentative taxa were the Naviculaceae andNitzschiae-Navicula sp., Entomoneis alata var.pulchra, Nitzschia sp., Nitzschia longissima, N.sigma var. intercedens, N. circumsuta, Bacillariaparadoxa. Some Cyanobacteria (Lyngbya andOscillatoria) were also occasionally present insamples. The Dinophyceae were rare except forScrippsiella sp.The coastal zone includes the archipelagos(Connétable Is., Rémire Is., Salut Is.). Although thehydrographical parameters have wide ranges(salinity varying from 12 to 35‰ for instance), thiszone is more stable and highly productive, especiallythe surface waters. Pelagic diatoms are predominantin the phytoplankton, though the Dinophyceae arealso important during certain seasonal periods.Skeletonema tropicum is responsible for majorblooms in May that are often coupled with lowernumbers of Ceratium fusus (Dinoflagellate).Coscinodiscus asteromphalus, Thalassionemanitzschioides, Odontella mobiliensis, Chaetocerossubtilis var. abnormis, and Cerataulina dentata(Diatomophyceae) are also present in this area, asare Noctiluca scintillans, Ceratium lineatum, andProtoperidinium oblongum (Dinophyceae). Dytilumsol is dominant in August, associated with Nitzschiapungens, Chaetoceros appendiculata, and Ceratiumlineatum. In October, Coscinodiscus jonesianus is


Simposio.p65 05-04-04, 11:12 a.m.311

312

Gayana 67(2), 2003

the dominant species, associated withCoscinodiscus karstenii, Chaetocerosappendiculata, Thalassio-nema nitzschioides,Diplopeta bomba, and Ceratium lineatum.The shelf province (>50 m depth) is dominated bya single diatom, Thalassionema nitzschioides anda cyanobacterium, Oscillatoria (Trichodesmium) cf.thiebautii; the other secondary species belong todifferent pelagic genera: Proboscia (Rhizosolenia)alata, Pseudosolenia (Rhizosolenia) calcaravis,Hemialus sinensis, and Climacodium fraufel-dianum. Dinoflagellates are also characteristic ofthis system, especially Ceratium tripos var.atlantica, C. massiliense, C. trichoceros, C. vultur,C. contortum, etc. Paulmier (1993) indicates thatthe dominant species in the coastal area from De-cember to July are the “Skeletonema-Thalassio-nema-Coscino-discus-Ceratium society” which cor-responds to Group II of Margalef & González-Bernáldez (1969) who characterized a similarphytoplanktonic coastal community in Venezue-lan waters. This is temporarily followed by a“Coscinodiscus association”.The oceanic area is dominated by the speciesNitzschia pungens and the genus Rhizosolenia.This association corresponds to Group II as de-fined by Dandonneau (1971) for the Ivory Coastwaters, confirming the ubiquity of the tropicalAtlantic species. Even if the phytoplankton isdominated by Diatomophyceae (Chromophytes)and by Dinoflagellates (Pyrrhophytes), other taxasuch as Euglenophytes (Euglena spp.), andChlorophytes (Spirogyra spp., Closterium spp.)are often present in brackish estuarine and litto-ral waters. The Chrysophyceae is particularlyimportant with Phaeocystis (Order: Prymne-siales) represented by 2 species, P. pouchetii anda larger form which is very abundant under cer-tain hydrochemical conditions. The Cyano-bacterie of the Schizobacteria group also peri-odically constitute a significant biomass in pre-oceanic neritic waters and in the littoral area.Maia de Oliveira (2000) studied the phytoplank-ton in 2 estuarine systems (the Sinnamary andIracoubo Rivers). The effect of tidal changes onthe phytoplankton diversity of the Kaw Riverestuary, were reported by Vaquer (2000). At neaptides, the dominant genera were largeCoscinodiscus, Thalassionema, and Odontella,whereas at spring tides, the community was domi-

nated by Skeletonema associated with Odontella.These species were also detected in in the sub-surface layer of shelf waters, associated with thegenera Denotula, Hemiaulus, Chaetoceros, Rhizo-solenia (Diatoms), and Ceratium furca and C. fusus(Dinophyceae). Very low cell abundances charac-terized the wet period. The majority of the freshwater genera were represented by differentDesmiidae (Closterium, Pleurotaenium,Micrasterias torreyi, M. furcata, M. abrupta, andM. laticeps, Staurodesmus, Staurastrum, Xan-thidium, Desmidium, Cosmarium, Sphaerozosma,Spondylosium), Chlorophyceae (Eudorina,Ankistrodesmus falcatus, Botryococcus braunii),Euglenophyceae (Lepocinclis, Traochelomonashispida, Euglena, Phacus), and Dinophyceae(Ceratium, Peridinium).

ZOOPLANKTON IN THE ESTUARINE AND COASTAL WATERS

OF FRENCH GUIANA

Protozoans make up an important part of thepelagic biomass and are normally flagellates,dinoflagellates and diatom consumers, such asthe Sarcomastigophora, classes of the Rhizopodaand Actinopoda represented by the generaGranuloreticulosia (Foraminidae), Radiolariansand Acantharians, and also the Ciliophoracomprising the Spirotriches (Tintinnidae). Thegenera Tintinnopsis, Favella, and Coxliella arecommon in estuarine and littoral waters, whereasRhabdonella, Epiplocylis and Eutintinnus aremore oceanic (Paulmier 1993). In the estuarinezone, zooplankton population’s maxima are inMay, July, and December and, very often, consistof holoplanktonic larvae, such as copepod naupliiand adults of the genera Oithona, Cyclops, andParacalanus (P. cf. crassicornis). The Cladocerae.g. Bosminia probably originate from fresh-water. The Rotifers and especially the Tin-tinnidae, Tintinnopsis karajacensis, Tintinnopsissp., Codonaria fimbriata, and Favellapanamensis are the other major representativesof the zooplankton. The composition of thezooplankton is mostly homogeneous from thecoastline out to 50-60 m depth. Oithona sp.,Acartia tonsa, the nauplii of various copepodsand Tintinnopsis sp., are the most frequent speciesof this area. The zooplankton is very much morediversified in the oceanic area and includes pelagic

Simposio.p65 05-04-04, 11:12 a.m.312

313

molluscs. Two size-classes were considered byLam Hoai & Rougier (2000, 2002) in their study ofthe zooplankton: microzooplancton (40-150 µm)and mesozooplancton (>150 µm).The mudflat station is different from the 2 otherstations of the Kaw River estuary, in the channelof the river itself and in the Paul Emile creekwhich drains a mature mangrove. During the wetseason and high flow period, the Kaw Riverestuary becomes an extension of the riverineecosystem. The drainage waters from the Kawswamp are characterized by very low abundancesand biomasses of zooplankton with a strongpredominance of Rotifers, in terms of abundance.Sixty-one taxa corresponding to 27 taxonomicgroups have been identified. Tintinnopsis is theprincipal genus present in microplankton assem-blages. The dominant species of Copepods wereParacalanus crassirostris, Oithona ovalis, andAcartia giesbrechti whereas the dominantTintinnids were Codonellopsis and Favella inneap-tides and Tintinnopsis in spring-tides. Thepelagic copepods, Paracalanus crassirostris,Acartia giesbrechtii , and Oithona ovalis ,provided 63% of the total biomass in neap-tidesas opposed to only 31 % in spring-tides. Rotiferpopulations were represented in neap-tides bySynchaeta and Trichocerca but were practicallyabsent in spring-tides. On the other hand, theChaetognatha Sagitta frederici constituted a ma-jor part of the biomass in spring tides. Thedetection of rare taxa such as Pseudodiaptomusmarshi, Ostracods, Oikopleura, Cletodidae,Diosaccidae, Canthocamptidae, the hydromedusaObelia, the Copepod Eucalanus, Decapod larvae,Polychaeta larvae, Anthomedusa, Isopod larvae andNematods varied greatly between flow and ebb tidesand day and night periods. This hydrological contextfor the wet season is radically different from thatof the dry season and the reduced flow of the riverwhen the estuary is regularly subjected to tidal in-trusions of saline water. This period is characterizedby relatively significant estuarine biomasses ofzooplankton whereas populations and biomassesupriver are considerably smaller. This seasonalenrichment of the estuarine zone is thus relateddirectly to the penetration of the littoral waterswhich fertilize and increase the local productivityand also transport the zooplankton communitiespresent in both the littoral and coastal waters.

LITTORAL BENTHIC COMMUNITIES ANDPOPULATIONS OF FRENCH GUIANA

LITTORAL MANGROVE ECOSYSTEMS: THEIR STRUCTURE

AND ECOLOGICAL FUNCTION

When the massive migrating mud waves, whichstretch 1,100 km along the northeast coast of SouthAmerica, from the mouth of the Amazon River tothat of the Orinoco River, settle out, they producethe mudflats that are progressively colonized bymangroves which extend along almost all of the320 km coastline of French Guiana (Fig. 3; Prost1989), occupying a band from a few meters to about15 km wide (Vignard 2001). The mudflats are rap-idly covered by mats of microalgae that find thelight conditions optimal for their growth. Thesemicroalgae, dominated by colony forming diatoms,have the ability to migrate into the sediments, ac-cording to the tidal and daily irradiation cycles.Progressively, a benthic community of Nematods,Tanaidacea, and Foraminifera becomes establishedwithin the mudflat (Vignard 2001, Guiral 2002). Anumber of species use the tidal cycles to benefitfrom these resources: limicole birds and crabs atlow-tide, and numerous fish and postlarval and ju-venile shrimp at high water. Despite high levels ofspecies biodiversity in the ecosystem as a whole,the number of plant species is relatively few in thecoastal mangroves, only 4 indigenous genera be-ing represented-Avicennia, Rhizophora, Lagun-cularia and Conocarpus (Dodd et al. 1998). Fivespecies of mangrove trees have been identified: thered type (Rhizophora mangle and R. racemosa,Rhizophoracea), the grey-black type (Lagunculariaracemosa, Combretacea), and the white type(Avicennia germinans, Verbenaceae). A very rarespecies, Conocarpurs erecta (Combretaceae), islocated at only one site in French Guiana. Thesemay be separated into coastal and estuarine man-groves (de Granville 1986). The white type pre-dominates in coastal mangroves, but recently de-posited mudflats are colonized firstly by the grey-black type and only later by A. germinans. The ge-nus Rhizophora dominates upstream from the es-tuaries. In parallel with the changes in hydrography,a sequence can be recognised in the shoreline-main-land direction: young trees growing on the even,fluid muds in the intertidal zone, then mature for-ests of large trees (medium density and low mortal-


Simposio.p65 05-04-04, 11:12 a.m.313

314

Gayana 67(2), 2003

ity). On the older alluvia are the senescent stagesof the trees (high mortality). The aim of the ongo-ing mangrove study (PNEC program, Fromard et

al. 2003) is to analyse the process of mangrovecolonization and to identify its role within thecoastal food webs.

FIGURE 3. Migration of the mudflats along the Guianese Littoral. Situation in 1988 (from Prost 1989, in Frouin 1997).

FIGURA 3. La migración de las marismas a lo largo del litoral de Guyana; la situación en 1988 (de Prost 1989, enFrouin 1997).

THE PHYSICAL CHEMISTRY OF THE LITTORAL MUDFLAT

WATERS AND ITS ECOLOGICAL IMPLICATIONS FOR

BIODIVERSITY

As already mentioned, in the dry season, ‘‘marine’’waters contribute to the transport of phosphate intothe rivers, whereas, in the wet season, the ebb tidescarry particulate suspended mineral and organicmatter out to sea (Vignard 2001, Guiral 2002); inthis context, a large part of the phytobenthos couldalso be moved within the water column.The water draining from the coastal mangroves isrich in nutrients and suspended matter and tends tobe brackish though its salinity varies greatly, de-pending on the rainfall. The fauna which live inthese habitats is thus characterized by euryhalinespecies. According to Rojas-Beltrán (1986), themangroves in French Guiana shelter some 100 spe-

cies of fish and 34 species of crabs and shrimps.Some of them live in these habitats permanently,while others, e.g fish and crustaceans, temporarilyvisit the mangroves to feed (Hogarth 1999), to pro-tect themselves from predatory pressure (Primavera1997), or to acheive part of their life cycle. Thus,various species find that these systems provide thebest conditions to ensure part of their developmentcycle: shrimps (Primavera 1998), postlarval andjuvenile fish, and the adult stages of crabs (Jones1984). The young stages of these species are mainlydetritivores (Rojas-Beltrán 1986) and are thereforeat the base of the trophic chain of the estuarine sys-tem. Significant populations of Penaeus subtilis andPlagioscion sp. of small average size and the ab-sence of sexually mature individuals indicate therole of the mudflats as nurseries for these species.These two taxa make up the largest trophic level,

Simposio.p65 05-04-04, 11:12 a.m.314

315

their juvenile stages being omnivores capable offeeding on detrital material produced by the sur-rounding mangrove. The adults of Platystachuscotylephorus and Potamotrygon hystrix constitutea secondary trophic level, the primary being carni-vores. Lastly, the adults of Plagioscion sp. andCentropomus sp. are intermediate carnivores (Rojas-Beltrán 1986). Of the 22 species found in this mudflatsystem, 9 are considered to be permanently estua-rine, seven mainly freshwater, and six mainly ma-rine. Based on the stage of maturity and the diets ofthe taxa in samples described by Odum & Heald(1972) and (Rojas-Beltrán 1986), it would appear that41% of the captured species would be shrimp con-sumers when adults (Caranx sp., Lutjanus sp.,Centropomus sp., Arius sp., Plagios-cion sp.,Platystacus cotylephorus, Potamotrygon hystrix,Gobioides sp., and the crabs, Callinectes sp.).

PROKARYOTE DIVERSITY AND AN ANALYSIS OF COMMUNITY

STRUCTURE IN THE MOBILE MUD DEPOSITS OF FRENCH

GUIANA

Venkateswaran et al. (1998) were the first to haveisolated a bacterium (Shewanella amazonensis)from Amazonian shelf coastal muds in the north-ern Amapá region where shore-attached mudwaves are first formed. Madrid et al. (2001) havesince provided a molecular census ofprokaryotes in a shore-attached coastal mudwave, 3-4 m thick, migrating to the northwestover a relict mud surface. These authors exam-ined the relationships between the inferred mi-crobial community and a range of seabed sedi-mentary and geochemical properties, and itspotential as an indicator of hydrodynamic proc-esses. A sequence analysis, extracted from asubsurface sediment layer (10-30 cm) of 96 non-chimeric sequences showed the majority of themicrobes to be bacteria. The diversity was high,with 64 unique sequences, and Proteobacteriawere dominant. Bacterial sequences belonged tothe Cytophaga-Flexibacter-Bacteroides group,Actinobacteria, Planctomycetes, Cyanobacteria,low-GC Gram-positive, K, Q, and N subdivisionsof Proteobacteria. A sizeable fraction of se-quences from the Kourou-Sinnamary library arenormally found in water column populations,reflecting the frequent entrapment of suspendeddebris into the underlying sediments. Dominant

sequences were related to Gelidibacter algens(Cytophaga-Flexibacter-Bacteroides group),Actinobacteria, Sulfitobacter and Ruegeria spp.(K-proteo-bacteria), all of which are chemo-organotrophs, consistent with abundant labileorganic carbon. Frequent resuspension,reoxidation of bottom sediments, and re-deposi-t ion, coupled with the entrapment ofallochthonous organic particles including organ-isms, create transient environmental complexityand promote high microbial diversity. Further workon the microbiology and biogeochemistry of thesemobile muds is being planned.The productivity and adaptation of the photosyn-thetic biofilms that colonize the littoral mudflatsStrong ecological interactions, including compe-tition, exist between microphytobenthos and man-grove vegetation. Photosynthetic biofilms, onemainly consisting of cyanobacteria and another ofdiatoms, were sampled on a mudflat of the Kawestuary (Guiral et al. 2001, Sygut 2002). Foursediment samples were taken from the Kawmudflat: one from the central part of the mudflatin the course of being colonized by a phytobenthiccommunity including diatoms and cyanobacteria,another from the upper sector colonized by aphytobenthic mat, very largely dominated byChlorophyceae, a third from the central part of thissector dominated by mobile pennate diatoms withinthe sediment, depending upon the irradiance, andthe last from the lower part, where there was onlyone settlement of very large centric diatoms,inherited from of the oceanic area. A fifth sample,taken from the zone of a mature Rhizophora andAvicennia mangrove, was of a sediment verypartially colonized by cyanobacteria and activelyexploited by crabs. New studies are planned todetermine the factors which control the deve-lopment of autotrophic biofilms and theirproductivity.

DIATOM DIVERSITY IN THE MUDFLATS AND MANGROVES

OF THE KAW RIVER ESTUARY

The diatom communities in 85 samples of surfacesediments taken from habitats ranging from mo-bile mud to stabilized mangroves of the Kaw Riverestuary during 3 cruises-at the beginning of the dryseason (July 2000) and in the rainy season (Janu-ary 1999 and December 2000)- were studied by


Simposio.p65 05-04-04, 11:12 a.m.315

316

Gayana 67(2), 2003

Sylvestre et al. (2002). 178 taxa belonging to 51 gen-era were identified. The diatom communities weredominated by periphytic species; only 34 specieswere identified as holoplanktonic forms. Thetychoplanktonic species were represented by 2 typesof Synedra in 3 samples. All of the identified spe-cies were characteristic of saline conditions. Thestrictly marine forms were all planktonic. Mostof the periphytic forms were species observed inlittoral as well as in continental saline situationswhereas the diatom communities were all char-acteristic of coastal systems. Five species(Coscinodiscus centralis, Cymatodiscusplanetophora, Cyclotella stylorum, Gyrosigmapeisonis and Thalassionema nitzschoides) werepresent in all of the samples.The periphytic forms were mostly of the generaGyrosigma, Pleurosigma and Nitzschia; these liveboth on and in the mud, their migration into thesediment depending upon sediment resuspensionand the irradiance conditions. A freshwater spe-cies (Eunotia spp.) was observed in only one sam-ple taken upstream of the estuary. The samplestaken on the unstabilized mudflat contained thetypically marine planktonic species,Coscinodiscus centralis, Cyclotella stylorum, andThalassionema nitzschoides, which are charac-teristic of the Atlantic Ocean. These are found,however, not only on unstabilized mudflats alsoin mature mangroves and are indicators of thepenetration of oceanic waters far into the estu-ary. The samples taken on the fluid mudflat andthe slikke were dominated by Gyrosigma spp.,which possesses a high degree of mobility withinthe sediment. Finally, in the samples from themangrove swamps stabilized by vegetation,Nitzschia spp., considered to be mobile epipelicforms, and Navicula spp., characteristic of muddyshores, were predominant. The mature mangrovesamples were characterized by a greater specificrichness and a greater diversity than those fromthe other locations. The parameters such as sa-linity, nutrient concentrations, and pH have agreat influence on species diversity. This studysuggests that the motile epipelic species(Gyrosigma spp. and Nitzschia spp.) are indica-tors of fluid mudflats, with a gradation from theoceanic influenced area mostly dominated byGyrosigma spp. to progressively more stable ar-eas dominated by Nitzschia spp. Species of the

genus Navicula characterize the settling areaswhich are subject to higher variations of the en-vironmental parameters. This study demonstratedthat the penetration of oceanic waters has a biginfluence on the ecosystems of the Kaw estuary,purely freshwater habitats occurring well up-stream from the estuary.

FORAMINIFERAL BIODIVERSITY

In the 37 surface sediment samples collected inJanuary 1999 and July 2000 for the study of themicrofaunal biodiversity in the mangrove swampsand mudflats of French Guiana where strong sea-sonal variations occur, 44 species were identified(Debenay et al. 2002). The main factor regulatingthe distribution of foraminiferal assemblages is thehydrodynamics of the estuary, characterized by theinfluence of both saline coastal water and low cal-cium fresh water, with major seasonal differences.The coastal end member is dominated by the cal-careous species Ammonia tepida, A. parkinsoniana,and Cribroelphidium spp. whereas the continental(freshwater) end member is characterized by theagglutinated species Miliammina fusca andTrochamminita irregularis. The calcareous speciespenetrate the estuary, even as far as the mangroveforests, during the dry season but totally disappearfrom the estuary during the rainy season. The otherfactor affecting the distribution of the Foraminiferais their vertical elevation which determines the pe-riod of aerial exposure and the colonization bymangrove trees. Foraminifera are very rare on oreven absent from exposed mud banks containingcracks, but begin to grow as soon as youngAvicennia are present. Both the canopy and the de-tritus of the mangrove forest protect the sedimentfrom heating and drying and, thus, increase in sa-linity caused by the sun and wind. The distributionof the agglutinated species in the mangrove swampsis, as a result, closely related to the presence of themangrove trees.

MEIO- AND MACRO-BENTHIC BIODIVERSITY IN THE LIT-TORAL MUDFLATS OF FRENCH GUIANA

The meiofauna of the Kaw mudflats are largelydominated by Nematods (Ragot 1999, Boucher2000). The “marine slikke” zone has significantpopulations of adult and nauplii stages of

Simposio.p65 05-04-04, 11:12 a.m.316

317

Harpacticoidae Copepoda (Crustacea) andTurbellariae (Annelida). Due to their high indi-vidual biomasses, the insect larvae found withinthe inner mudflats represent 50% of the totalbiomass. The importance of the Tanaïdaceae atsome locations on the Kaw river mudflat and the“estuarine slikke” of the mudflat were confirmedby a comprehensive meiobenthic survey that in-cluded the young stages of this group.The Nematods were the numerically dominantgroup of the meiobenthic fauna. A total of 66species were identified with a mean of 16 spe-cies per sampling site and a maximum of 28 spe-cies in the mature Rhizophora mangrove. TheMonhysteridae family was the most abundant andthis characterizes the nematofauna as a commu-nity of non-selective detritivores. Two species ofthis family represented over 25% of the nematodsanalyzed. The second community is representedby the specific epistratum grazers, Dicromodoraand Metacrhomadroides. These genera areadapted to the grazing of diatoms and are domi-nant on the marine slikke.Justou (1999), Glevarec (1999) and Clavier(2000) have reported the presence of 26macrobenthic taxa in the Kaw mudflat area. TheTanaïdacea Crustacea is the most abundant taxa,representing 75% of the total abundance, fol-lowed by the Polychaeta and Oligochaeta(Annelids). The communities were found to below in diversity though the populations covereda wide range of abundances; this structure is com-mon in an environment subject to a major physi-cal constraint. It was possible, as a result, to dif-ferentiate between the stations of the stabilizedmudflat, the mangrove and mudflat at the youngstage of tree colonization, the mudflat marineslikke, and the areas colonized by the dense com-munities of Tanaidaceae. The total biomass wasvery low over the mudflat (a factor of 10 lessthan the mean biomass) except within the drain-age channels. The macrobenthic biomass was, onthe other hand, high in the estuary border slikkesand, especially, in the mangrove zones.The small-sized macrobenthos was dominated bydeposivores, mostly little Peracarid Crustacea andCapitellidae Annelida. Suspensivores were veryrare and only some Cirripedae (Crustacea) andMytilidae (Mollusca) were observed on floatingbranches. The low numbers of suspensivores are

related to the highly turbid littoral and estuarinewaters.

THE CARCINOLOGICAL FAUNA OF A FRENCH GUIANA

MUDFLAT COLONIZED BY MANGROVES

The extremely rapid establishment of a mangrovemakes it possible to follow, on a very short timescale (3 to 5 years), the progressive transformationof an unstabilized mudflat into a mangroveinhabited by the carcinological fauna specific to thistype of habitat. The interactions between vegetationand crabs is demonstrated by the occurrence ofspecies which depend first on the shade providedby the trees and then on the production of leavesand litter which constitute their food (Amouroux& Tavares 2002): Goniopsis sp. feeds on the youngfoliage of trees and Ucides sp. consumesdecomposed leaves, whereas Aratus pisonii dependson the primary production of Rhizophora trees andthe epibiontes of their stilt roots.The gradual disappearance of Uca maracoani isrelated to changes in its habitat. Initially, the lossof mud without vegetation narrowed its surface andthe mud covered with vegetation became compacted.Uca maracoani is now, therefore, confined to thesloping edges of the river. Its place has been occupiedby other Uca spp. and also by Ucides cordatus. Thesettlement of Rhizophora at the edge of the river allowsthe development of Aratus sp. The population densitiesof the various species increase as the mangrovedevelops. The appearance of Ucides sp. and the anas-tomoses of the burrows of Uca sp. in 2001 were indi-cations of increasing bioturbation. The survey of thismudflat made it possible to show a process of faunalsuccession and colonization of the different habitatsnear the littoral mudflats. There are plans to continuethis research, as part of the PNEC program, over alonger period, to supplement it with a study of theriver margins colonized by Uca sp., and to follow itup with a senescent mangrove area.

STUDIES ON PARTICULAR PROTECTED SPE-CIES CONSERVATION STRATEGIES

The coast of the Guianas is a mix of vast mudflats,narrow sandy beaches, mangrove swamps, wetsavannas, and brackish water creeks. The mangroveforests of the Guianas are among the most impor-tant and least degraded in the world and are home


Simposio.p65 05-04-04, 11:12 a.m.317

318

Gayana 67(2), 2003

to millions of North American migratory birds. Off-shore, the strong Guianas Current flows east to westcarrying the nutrient-rich mud of the Amazon andthe local smaller rivers and creeks. In a continualprocess of erosion and rebuilding, the Guianas Cur-rent seasonally creates and then washes away hugemudflats and wide stretches of sandy beach (Fig.3). This process is important because the Guianasprovide nesting sites and feeding grounds for someof the largest remaining populations of 4 speciesof sea turtle. Mangroves provide critical habitatsfor many marine species such as shrimp, tarpon,bonefish, and rays. Within the Guianas, the mainthreats to biodiversity are the removal of man-groves; over-hunting of turtles, birds, and othermammals; incidental catches of turtles by shrimptrawlers and fisheries activities, the poaching ofturtle eggs; over-fishing; increasing pesticide andfertilizer use in expanding rice fields; bauxite min-ing operations; and land clearance for livestock. Inaddition to the known threats, there is the possibil-ity that other industries, such as sandmining,goldmining, and oil development may also be di-minishing the biodiversity of this ecoregion.

STUDIES OF THE BIOLOGY AND ECOLOGY OF MARINE

TURTLES (FROM THE WWW SITE OF WWF ©)

Together with partners at STINATSU (the Foun-dation for Nature Conservation), indigenous com-munities in Suriname, and KAWANA in FrenchGuiana, the WWF has been supporting sea turtleconservation in the Guianas for over 20 years.Since 1999, with the assistance of WWF Guianas,this regional approach has gradually taken shape.In recent years, local organizations and commu-nities have begun to play an even more pivotalrole in the conservation and management of thesespecies (Talvy et al. 2001, Fretey et. al. 2002);recently, they have completed a Regional SeaTurtle Conservation Strategy that will provide theregional program with a framework and goals forfuture conservation work. In all 3 countries, seaturtle conservation activities include research andenforcement, and developing ecotourism and al-ternatives to unsustainable fishing practices andthe harvesting of turtle meat and eggs. Classicresearch techniques, such as surveys, and newresearch techniques, like satellite tracking, PIT-tagging, and genetic research, are enabling

Guianese and WWF scientists to better under-stand turtle biology. In French Guiana, sea turtleconservation activities are coordinated by theDIREN (the Ministry of Natural Resources forFrench Guiana). Partners working with DIRENinclude associations such as SEPANGUY andAmerindian organizations such as Kulalasi. TheAmana Nature Reserve, WWF, ONCFS, Kwata,Université d’Orsay and CNRS are also active part-ners in local sea turtle conservation.Leatherback (Dermochelys coriacea), green (Che-lonia mydas), olive ridley (Lepidochelys olivacea),and hawksbill (Eretmochelys imbricata) turtles neston the beaches of French Guiana. With the exceptionof the hawksbill, for which there are not enough data,the nesting seasons are well-known: green turtles(January-May), olive ridleys (May-September), andleatherbacks, almost all the year round but dividedinto two distinct nesting seasons, whit a minor peakin December/January and a major peak during April-July.The primary nesting sites in French Guiana are lo-cated at Awala-Yalimapo, along the Point-Isère/Organabo coastline, and at the urban sites of Kourouand Cayenne. The Awala-Yalimapo Beach (AmanaNature Reserve) is historically considered the mostimportant single nesting site in the world for theleatherback sea turtle; during the primary peak sea-son (May-June), more than 200 of them may nest therein a single night. It is also an important nesting sitefor green turtles, though this species has not been for-mally monitored. Olive ridley turtles (on average, lessthan 10 nests per year) and hawksbill turtles appear tobe only occasional nesters. WWF-France has gradu-ally refocused its activities on to the protection of nest-ing females during the leatherback egg-laying season(the Kawana Campaign, Talvy et al. 2001), in col-laboration with Kulalasi (an Amerindian organizationbased in Awala-Yalimapo) and the Amana NatureReserve staff.Beaches along the Pointe-Isère/Organabo coastlineshift with changes in the shoreline structure, mak-ing consistent monitoring difficult. Nevertheless, thearea is known to be an important nesting habitatand is considered to be the main nesting area forgreen turtles in the country.Finally, there are 2 important “in-town” sea turtlenesting sites, in Kourou and Cayenne, in FrenchGuiana. They nest on 4 beaches, covering a distanceof about 4 km, in the vicinity of Kourou. In Cay-

Simposio.p65 05-04-04, 11:12 a.m.318

319

enne, nesting sea turtles are currently using 6 mainsites, spread over about 12 km. These beaches are inan urban setting with buildings and other man-madestructures often only a few meters away from thenests. Two local organizations, KWATA andSEPANGUY, are monitoring these sites. Their re-ports show the importance of these sites for oliveridleys and leatherbacks (Talvy et al. 2001).

THE DISTRIBUTION, HABITAT, AND CONSERVATION STATUS

OF THE WEST INDIAN MANATEE IN FRENCH GUIANA

The manatees, Trichechus manatus, may be lessabundant than in the recent past (de Thoisy et al.2002), but are still present and regularly sighted allalong the coast and in estuaries, up to 80 km inlandfrom the open sea. The main habitats for the mana-tees are estuarine mangroves. At the moment, theirsecretive behaviour, fairly undisturbed estuarinehabitats, species scarcity, and protection laws cre-ate an optimistic outlook for the future of the mana-tee populations in French Guiana. The manatees arealso encountered on nearby rocky shores (CayenneIsland, Malmarouny, Ilet-la-Mère and Rocky pointat Kourou) and up to 80 km upstream in some ofthe larger rivers as the Maroni, the Approuague andthe Oyapock. As the alluvial coastal plain is quitenarrow, their habitats are naturally restricted.

A STUDY OF SOTALIA FLUVIATILIS (CETACEA, DELPHINIDAE)IN COASTAL WATERS

The results of a bibliographical study coupled withfield work (direct observations and the collectionof data since 1997) on the distribution and possiblethreats to Sotalia fluviatilis in the waters of FrenchGuiana have been reported by S. Bouillet (2002).These dolphins are observed along almost all of thelittoral area. They seem to be present all throughthe year towards the east of the French Guiana coastbut seem to be more frequent in the dry seasontowards the west; this could be connected with theoccurrence there of less turbid water and better foodstocks. They are rarely observed at the mouths ofand within the principal rivers (Oyapok and Ma-roni) where river traffic is rather heavy, but morefrequently within the mouths of the secondary rivers(Larivot and Mahury) and around the “du Salut”and “Connétable” Islands. Habitat destruction seemsto be less important than the 3 year decline in the

shrimp populations, which has greatly reduced amajor food supply for the dolphins.

THE BIRDS OF THE LITTORAL ZONE OF FRENCH GUIANA

More than 200 of the 700 species of birds whichpopulate French Guiana are essentially or com-pletely habitants of the littoral wetland areas (Hansen& le Dreff 2002), and more than two-thirds of the30 birds cited in the “Red book of the endangeredspecies of the French overseas regions” (Thiollay1988) live in these wet coastal systems. The wild-life of the littoral of French Guiana, which has beenless studied than that of the rainforest, presents avery particular evolutionary dynamic which con-stantly modifies its structure.Three of the 10 species of ducks (Anatidae) observedin French Guiana are strictly migratory Anas discors,A. americana, and A. clypeata (Hansen & le Dreff2002). Dendrocygna autumnalis and Anasbahamensis are nesting species in French Guiana.The great majority of the Anatidae are located onthe western part of the coast and particularly in theMana lagoon. This particular location has been pro-tected by creating the Amana Regional Natural Re-serve, as well as the Kaw swamp Regional NaturalReserve.The emblematic red ibis, Eudocimus ruber, is a pro-tected species along the whole of the French Guianacoast and lives at the mouths of rivers or in the coastalmarshes. Not less than 24 species of herons are presentin French Guiana, occupying various habitats such asmudflats and littoral lagoons, freshwater marshes andforest creeks. The most abundant species are Egrettathula and E. caerulea. These species share their habi-tats and nesting sites with 6 other species, e.g. Egrettatricolor. Egretta alba is frequently observed in marshesand rice plantations as well in the littoral. Ardea cocoiis the most numerous representative species of theArdeidae in South America.Among the rarest species, the pink “spatule”, Ajaiaajaja, is present at littoral sites of difficult accessand Mycteria americana is mostly observed incoastal lagoons. Some small groups of pink flamin-gos (Phoenicus ruber) are regularly seen comingfrom Suriname and Amapá State in Brasil.Nycticorax nycticorax, N. violacea, and Cochleariuscochlearius are small Ardeidae species that live indense mangroves and reproduce with other Ardeidaeand the red ibis.


Simposio.p65 05-04-04, 11:12 a.m.319

320

Gayana 67(2), 2003

Some birds, not strictly marine, inhabit the littoralfreshwater marshes; typical of these are Ixobrychusinvolucris, I. Exilis, Botarus pinnatus, and Zebrilusundulatus. On the other hand, Butorides striatus isa very common green heron that occupies differentparts of the coastal plain, as does Bubulcus ibis.Twenty-seven species of North American limicolousbirds have been recorded in French Guiana. “Small”limicolous birds include most of the sandpipers,Calidris pusilla being the most abundant, and thenCharadrius semipalmatus. Recent new censusesof limicoles were carried out by ONFCS and GEPOG.Small species arrive during their post-nuptial migra-tion between August and October. Thereafter, a partof the community migrates towards the Braziliancoast and, in January-February and April, they re-turn to the Arctic. Some of the large limicoles ob-served are Tringa flavipes and T. melaneuleuca,Arenaria interpres and Calidris canutus.The rocky islands in the coastal zone of FrenchGuiana provide refuges for marine birds such asFregata magnificens that travel up to 100 km awayfrom the coast, following the shrimp fishing ves-sels, as do seagulls. Nearly 500 couples of F.magnificens are observed all through the year inthe “Grand Connétable” Marine Natural Reserve.The numbers of the seagull, Larus atricilla, inFrench Guiana represent 20% of the Caribbean popu-lation and the most southerly community of thisspecies.The Cayenne stern, Sterna eurygnatha, is one ofthe most endangered species in the “GrandConnétable” Natural Reserve, as very few nestingcolonies are known. An international cooperativeconservation program has been established withAruba Island off the Venezuelan coast which hostsa similar sized colony of this stern. Sterna fuscata isrepresented by 250 couples on “Grand Connétable”island. Like Anous stodilus, this species often fliesaway from the highly turbid littoral areas as far as90 km offshore. The royal stern, Sterna maxima, isoften seen associated with the Cayenne stern onthe “Grand Connétable”.

DISCUSSION AND PERSPECTIVES

The information about marine biodiversity inFrench Guiana which has been described in thispaper is the result of studies carried out by re-

search teams coming from Metropolitan France,together with some local scientists, temporarilybased in French Guiana, working for various re-search institutions (IRD, IFREMER, CNES,Institut Pasteur, Université Antilles Guyane - UAG,CNRS, etc.), Governmental Agencies (DIREN,Natural Regional Parks) or different types of Non-Governmental Organizations, national (KWATA,GEPOG, SEPANGUY, etc.) and international(WWF). These scientists were or still are involvedin projects of limited duration (PNEC, PNRZH,LITEAU, etc.). Therefore, except for the programsthat dealt with species of particular commercialinterest or those already identified as endangeredspecies, the present review describes the outcomeof mainly short-term studies which focussed onspecific parts of the different ecosystems underprecise hydroclima-tological conditions. There is,therefore, a need for a more generalized long-termseries inventory of the existing data (includinggeographical distributions) and a more detailedassessment of marine biodiversity at the ecologi-cal, population and genetic levels. In addition,the available information needs to be comparedwith and, indeed, extended to the neighbouringcountries of the “Amazon-Guiana Ecotone” ormarine “Guianas Province”, from the mouth of theAmazon River to that of the Orinoco River andthe southern Caribbean Sea. A large reservoir ofexisting expertise could be called upon for carry-ing out these studies, if there were greater finan-cial and logistical support from national Frenchscientific institutions (Universities, CNRS, IRD,IFREMER, MNHN, INSU, and CNES). Thecreation of new academic careers to deal withthe environment, planned for the near future bythe local university, UAG, together with the for-mation of a local unit of the National ResearchCouncil (CNRS) and the renewal of IRD andIFREMER research groups in French Guiana,involving a significant number of local and met-ropolitan French scientists, are elements thatshould ensure the success of projects of medium-term duration involving also neighbouring coun-tries, financially and scientifically supported bynational and inter-regional programs. At present,only the ECOLAB network, initiated in 1993, isimproving coastal studies in all disciplinesthrough the communication and collaborationbetween scientists from northern Brazil, French

Simposio.p65 05-04-04, 11:12 a.m.320

321

Guiana and Suriname. Cooperation in marine re-search between an institute in French Guiana andanother in Venezuela has also been proposed.All these ongoing initiatives could be strengthedwithin the CoML Program. First of all, some studiescould be carried out at the ecological level for abetter understanding of the functioning and energyand material fluxes in the different estuarine, litto-ral, coastal, and open sea ecosystems already indi-vidually studied in previous and ongoing programs.Existing data, at different levels and scales, need,first of all, to be brought together in a commonGeographical Information System data base.Coastal oceanographic cruises covering the entirearea, supported by satellite imaging, would then bea good strategy for integrating local studies, thoughthe protocols used for data gathering would needto be standardised in order to compare the meas-urements and estimations of stocks and fluxes madein the different countries of the region.A major research effort is required to increase andcoordinate field observations of the littoral, not onlyby scientists but also by the local populations thatknow and benefit from these ecosystems. In thisway, an improved inventory of the known and stillunknown marine species, from microbes to turtles,dolphins, and birds, could be produced. For this, itwould be essential to cross fertilize the capabilitiesof all of the scientists involved in the area. It is alsoimportant to stress that most classifications arechanging rapidly as microscopic (SEM, TEM) andbiochemical and genetic probe techniques improveour knowledge and ability to discriminate betweendifferent species and taxa in general, and betweenmicrobial organisms in particular. Moreover, assess-ments of genetic diversity could be made by meansof international cooperation, in order to establishthe in situ diversity of communities and populations.This would allow the accurate identification, clas-sification, and incorporation into an inventory ofthe organisms present at different locations andduring the various seasons. The exchange of scien-tists and of students involved in postgraduate stud-ies and research should be facilitated in order toimprove the global vision of the personnel study-ing marine biodiversity in South America. Finally,comparative research on the biodiversity of analo-gous littoral and marine ecosystems in SouthAmerica (large river coastal plumes, upwellingzones, estuaries, narrow or extended shelves, shelf

edges, characteristic habitats of the littoral) wouldallow the development and application of commonstrategies for the assessment and management ofthe marine biological richness of the continent.This could begin with different strategies at local,interregional, and international levels, within a me-dium-term project such as the CoML program (10years), which envisages two or three projects as arecurrently being developed in French Guiana. Thefirst need would be to compare capabilities in or-der to see how much each participant can achieveonce the goals and time scales have been defined.The aim would be to identify what local studiescan be made fairly quickly in order to prepare thedifferent stages in the research strategy during thenext 10 years and thereafter.

ACKNOWLEDGMENTS

We would like to thank all of the colleagues men-tioned for the use of their published and/or unpub-lished data, and their long-distance or close sup-port, in the achievement of this review. Specialthanks go to J.P. Debenay and F. Sylvestre for theirdata and comments. Thanks are also due to Dr. G.H.Sala for allowing Dr. L.F. Artigas to work at theIRD Cayenne Center since 2000, and to all the tech-nical and administrative staff of the IRD Cayennefor their help. Dr. B. de Thoisy of the KWATA As-sociation in Cayenne is gratefully acknowleged forhis information concerning the conservation actionsthat are currently being undertaken in FrenchGuiana. Finally, we want to express our gratitudeto the local and national coordinators of the PNECProgram for their support.

REFERENCES

ABBES, R., Y. ALDEBERT, D. DOREL, C. LEROY, R. LEMEN, J.PRADO & C. SAINT-FELIX. 1972. Reconnaissancedes fonds de pêche de la Guyane Française. Cam-pagne de la THALASSA dans la région Antilles-Guyane, 15 juin - 1er septembre 1971 - Science etPêche, Bull. Inst. Pêches marit. 210: 1-22

AIZAWA, M., T. ARAI, E. FUJII, T. INADA, K. MATSUURA, T.MIYAKE, K. SASAKI, Y. SATO, T. SHIMIZU & T.UYENO. 1983. In: Fishes trawled off Suriname andFrench Guiana. Uyeno T., K. Matsuura E. Fujii(Eds). JARMAC: 1-519

AMOUROUX, J.M. & M. TAVARES. 2002. La faune


Simposio.p65 05-04-04, 11:12 a.m.321

322

Gayana 67(2), 2003

carcinologique de la vasière de Kaw (GuyaneFrançaise). In Compte rendu d’activité 2001-2002du Programme National Environnement Côtier -Chantier Guyane : 47-50. D. Guiral & J.P. Debenay(Ed.), IRD Cayenne, French Guiana.

ARTIGAS, L.F. & D. GUIRAL. 2001. Seasonal evolution ofphytoplankton size classes in an estuarine andcoastal system influenced by the Amazon Riverdischarge (French Guiana). Joint IAPSO/IABOAssembly: 2001. An Ocean Odissey. 21-28October 2001, Mar del Plata, Argentina.

ARTIGAS, L.F. & D. GUIRAL. 2002. Seasonal dynamics ofmicroplanktonic biomasses, along a dilutiongradient, from the Kaw River to the coastalwaters off French Guiana. VI WorkshopECOLAB, 23-29 September 2002, Belém –PA,Brazil.

BÉNÉ, C., 1996. Effects of market constraints, the remu-neration system and resource dynamics, on thespatial distribution of fishing effort. Can. J. Fish.Aquat. Sci., 53 : 563-571.

BERNADAC, L, G. DIALLO- BOURGUIGNON, J. ROSÉ & P.VENDEVILLE. 1999. Ressources halieutiques etappropriation de l’espace sur le plateau deGuyane Française.– 4ème Forum halieumétri-que, les espaces halieutiques-Juin 1999-Rennes,29 juin- 1er juillet 1999. Poster et résumé (Lesespaces halieutiques-Colloques et séminaires,591- 592).

BLANCHARD, F., A. CHARUAU, J. ROSE & J. ACHOUN. 2000.Analyse de la structure du système de pêche ar-tisanal guyanais. Introduction à sa dynamique.DOCUP Regis II 6.3. Rapp. Ifremer. 65 pp.

BONNET, M., M. LEMOINE & J. ROSE. 1975. Possibilitésde développement de la pêche côtière en Guyane.Première prospection (17 février au 1er mars1975). Science et Pêche, Bull. Inst. PêchesMarit., 245 : 1-12.

BOUCHER, G. 2000. Communautés benthiques des va-sières et des mangroves: le méïobenthos. In Bi-lan des opérations de recherche 1999-2000 duProgramme National Environnement Côtier -Chantier Guyane, dynamique des apports Ama-zoniens: 13-14. D. Guiral (ed.), IRD Cayenne,French Guiana.

BOUJARD, T. & R. ROJAS-BELTRÁN. 1988. Zonation longi-tudinale du peuplement ichtyque du fleuve Sin-namary (Guyane française). Rev. Hydrobiol.Trop. 21 (1) : 47-61.

BOUILLET, S. 2002. Etude du Sotalia fluviatilis (Cétacé,Delphinidé) en Guyane Française. Report of theKWATA Association, Cayenne, French Guiana.

BOUYSSE, P., H.R. KUDRASS & F. LELANN. 1977. Recon-naissance sédimentologique du plateau conti-nental de la Guyane française (missionGuyanmer 1975). Bull. BRGM, 4 (2):141-179.

BULLIS, H.R. & J.R. THOMPSON. 1959. Shrimp explora-tion by the M/V OREGON along the northeastcoast of South America. Comm. Fish. Rev., 21(11), 9 pp.

CADÉE, G.C. 1975. Primary production off the Guyanacoast - Netherl. Journ. of Sea Res., 9: 128-143.

CHARUAU, A., J. ROSÉ & J. ACHOUN. 2000. Évaluation dustock de crevettes Penaeus subtilis du platreaucontinental de Guyane française sous de nouvel-les contraintes. Influence des fermetures spatia-les et saisonnières. Rapp. Ifremer DG XIV/C/2,98/1212975/F, 69 pp.

CLAVIER, J., OCT. 1996. Centre ORSTOM de Brest. Chan-tier Guyane: Propositions d’actions de recher-che et demandes budgétaires pour 1997. Pro-gramme National d’Océanographie Côtière.

CLAVIER, J. 2000. Communautés benthiques des vasiè-res et des mangroves: le macrobenthos. In Bilandes opérations de recherche 1999-2000 du Pro-gramme National Environnement Côtier - Chan-tier Guyane, dynamique des apports Amazo-niens: 13. D. Guiral (ed.), IRD Cayenne, FrenchGuiana.

DANDONNEAU, Y. 1971. Etude du phytoplancton sur leplateau continental de Côte d’Ivoire. I. Groupesd’espèces associées. Cah. ORSTOM, ser.Oceanogr., 9(2): 247-265.

DE MASTER, D.J., B.A. MCKEE, W.S. MOORE, D.M. NEL-SON, W.J. SHOWERS & W.O. SMITH JR. 1991.Geochemical processes near the mouth of theAmazon River/ocean boundary. Oceanography,4: 15-20.

DEBENAY, J.P., D. GUIRAL & M. PARRA. 2002. Ecologicalfactors acting on the microfauna in mangroveswamps. The case of Foraminiferal assemblagesin French Guiana. Est. Coast. Sh. Sc., 55(4): 509-533.

DINTHEER C. 1986. Le développement économique guya-nais et ses ambiguïtés: la controverse pêche-ri-ziculture. Rapp. IFREMER, in L’environnementaux Antilles-Guyane, 17 pp.

DINTHEER, C. & J. ROSE. 1989. Distribution spatio tem-porelle de Penaeus subtilis au large de la Guyanefrançaise. Bien-fondé de l’interdiction de pêchedans les 30 mètres et propositions d’aménage-ment. Rapp.IFREMER, 88 pp.

DINTHEER, C. & R. KALAYDJIAN. 2002. Expertise sur lasituation de la pêcherie crevettière guyanaise2000-2001. Rapp. Ifremer 01/1214037F. 86 pp.

DINTHEER, C., R. ABBES, J.M. FRITSCH & P. CHARLIER.1985. Pêche et riziculture au Surinam. Impactde la riziculture sur les ressources halieutiques.Rapp. IFREMER, 50 pp.

DINTHEER, C., B. GILLY, J.Y. LE GALL, M. LEMOINE & J.ROSÉ. 1989. La recherche et la gestion de la pê-cherie de crevettes pénéidés en Guyane françaisede 1958 à 1988: trente années de surf. Equinoxe,28: 21-33.

DODD, R., Z.A. RAFFI, F. FROMARD & F. BLASCO. 1998.Evolutionary diversity among Atlantic coastmangroves. Acta Oecologica 19(3): 323-330.

DRAGOVICH, A., A.C. JONES & G.C. BOUCHER. 1978.United States shrimp surveys off Guinas andNorthern Brazil (1972-76). NMFS-NOAA Rep.

Simposio.p65 05-04-04, 11:12 a.m.322

323

DURAND, J. 1955. Possibilités de pêche des crevettes enGuyane Française - Campagne de l’ORSTOM II- Rapport IFAT

DURAND, J. 1959. Notes sur le plateau continental. Leséléments principaux de la faune et leurs relationsavec le fond. Cahier de l’ORSTOM. 3. 93 pp.

FAO/WECAFC. 2001a. Regional reviews and nationalmanagement reports. Fourth Workshop on the As-sessment and Management of Shrimp andGroundfish Fisheries on the Brazil-Guianas Shelf.Cumaná, Venezuela, 2-13 October 2000. FAOFisheries Report, No. 651. Rome, FAO. 152 pp.

FAO/WECAFC. 2001b. Report of the Meeting of Fish-eries Managers and Ministers of the WECAFCAd Hoc Working Group on Shrimp andGroundfish Resources in the Brazil-GuianasShelf. Port of Spain, Trinidad and Tobago, 26-29 March 2001. FAO Fisheries Report. Nº 650.Rome, FAO. 61 pp.

FAO/WECAFC. 2002. Report of the first Regional Con-ference on the Sustainability of Fisheries Re-sources in the Brazil-Guianas Shelf. Paramaribo,Suriname, 5-7 March 2002. Fisheries Report. No.676. Rome, FAO, 27 pp.

FOURMANOIR P. 1971. Requins de Guyane. FAO FisheriesReport: Symposium on investigations andresources of the Caribbean Sea and adjacentregions. Nº 71(2): 51-55.

FRETEY J., L. KELLE, G. TALVY & J. CHEVALIER. 2002. Lestortues marines. In C. Richard-Hansen & R. LeGuen: Guyane ou le voyage écologique: 224-239.Editions Roger Le Guen, PANACOCO, Garies,France.

FROIDEFOND, J.M., M. PUJOS & X. ANDRE. 1988. Migrationof mud banks and changing coastline in FrenchGuiana. Marine Geology, 84 (1-2): 19-30.

FROIDEFOND J.M., L GARDEL, D. GUIRAL, M. PARRA & J.F.TERNON. 2002. Spectral remote sensingreflectances of coastal waters in French Guianaunder the Amazon influence – Remote Sensingof Environment, 80: 225-232.

FROMARD, F., C. VEGA, C. PROISY & L. CADAMURO. (IN

PRESS). Coastal evolution and mangrove dynamicsin French Guiana over the last fifty years. A casestudy based on aerial and satellite remote sensingdata and field survey. Mar. Geol.

FROUIN P. 1997. Revue des connaissances sur la zonecôtière de Guyane Française – Document“Programme National d’Océanographie Cô-tière”, 85 pp.

GLEVAREC, M. 1999. Peuplements méiobenthiques d’unevasière au cours de son évolution vers un éco-système de mangrove. Maîtrise de Biologie desPopulations et des Ecosystèmes, Université Pa-ris VI, 30 pp.

GRANVILLE DE, J.J. 1986. Les formations végétales de labande côtière de Guyane française. In Le littoralguyanais. Fragilité de l’environnement. Ier con-grès régional de la SEPANGUY. Xème colloqueSEPANRIT. SEPANGUY/SEPANRIT. 1985,

Cayenne. 47-64.GUEGUEN, F. 1991a. Les crevettes profondes du talus con-

tinental de la Guyane française. 1 - Résultats desdeux campagnes de prospection réalisées en 1990(août et novembre) Rapp. IFREMER, 66 pp.

GUEGUEN, F. 1991b. Les crevettes profondes du talus con-tinental de la Guyane française. 2. Etudebiométrique de quatre crevettes profondes de laGuyane française. Rapp. IFREMER, 91pp.

GUEGUEN, F. 1993a. Compte rendu de la campagne‘‘RESUBGUY2’’ (mai 1993) sur le plateau conti-nental de la Z.E.E. guyanaise. Contrat F.E.D.E.R.DG XVI. Rapport intermédiaire, 50 pp.

GUEGUEN, F. 1993b. Compte rendu de la campagne‘‘RESUBGUY3’’ (octobre 1993) sur le plateau con-tinental de la Z.E.E. guyanaise. Contrat F.E.D.E.R.DG XVI. Rapport intermédiaire, 58 pp.

GUEGUEN, F., 2000. Distribution et abondance des pois-sons démersaux et de quelques autres organis-mes benthiques marins du plateau continental (0-60m) de Guyane Française. C.R. Acad. Sci. ParisLife Sciences 323: 775-791.

GUEGUEN, F. 2001. Notes sur la biologie de la crevette deprofondeur Aristeus antillensis en Guyane Fran-çaise. C.R. Acad. Sci. Paris Life Sciences 324:689-700.

GUIRAL, D. 2002. De vasière à mangrove et de mangroveà crevettes In C. Richard-Hansen & R. Le Guen:Guyane ou le voyage écologique: 196-201. Edi-tions Roger Le Guen, PANACOCO, Garies,France.

GUIRAL, D. & A. PLENECASSAGNE. 2002. Nature des ex-portations en fonctiondu stade de développementde la mangrove. Communication Colloque PNEC- 22-27 January 2002, Cayenne, France.

GUIRAL, D., R. DE WIT & F. SYLVESTRE. 2001. Caractéri-sation des communautés phytobenthiques aucours du stade de pré-colonisation biologique desvasières littorales de la Guyane (Estuaire de Kaw).8è Congrès Français de Sédimentologie, Orléans(France), November 2001.

HANSEN, E. & A. LE DREFF. 2002. Oiseaux d’eau du litto-ral guyanais. In C. Richard-Hansen & R. Le Guen:Guyane ou le voyage écologique: 202-217. Edi-tions Roger Le Guen, PANACOCO, Garies,France.

HOGARTH, P.J. 1999. The Biology of Mangroves. Ox-ford University Press, New-York, 228 pp.

IEDOM. 2001. La Guyane en 2000. Rapport annuel.172 pp.

JONES, D.A. 1984. Crabs of the mangal ecosystem. InHydrobiologia of the Mangal. F.D., & Dor I.,(Ed.). W. Junk, La Hague, 89-109.

JUSTOU, C. 1999. Caractérisation spectrale des diversesespèces majeures colonisant le marais de Kaw.Maîtrise de Biologie des Populations et des Eco-systèmes, Université de La Rochelle, 30 pp.

KEITH, P., P.Y. LE BAIL, P. PLANQUETTE. 2000. Atlas despoissons d’eau douce de Guyane. Tome 2, fas-cicule I. Batrachoidiformes, Mugiliformes,


Simposio.p65 05-04-04, 11:12 a.m.323

324

Gayana 67(2), 2003

Beloniformes, Cyprinodontiformes, Synbran-chiformes, Perciformes, Tetraodontiformes.Patrimoines naturels (M.N.H.N./S.P.N.), 43(I): 286 pp.

LAM HOAI, T. & C. ROUGIER. 2000. Communautésplanctoniques des vasières et des mangroves: lezooplancton. In Bilan des opérations 1999-2000de recherche du Programme National Environ-nement Côtier - Chantier Guyane, dynamiquedes apports Amazoniens: 13-14. D. Guiral (Ed.).IRD Cayenne, French Guiana.

LAM HOAI, T., C. ROUGIER & D. GUIRAL. 2002. Zooplanc-ton dans un estuaire du littoral de la Guyane. InCompte rendu d’activité 2001-2002 du Pro-gramme National Environnement Côtier - Chan-tier Guyane: 37-44. D. Guiral & J.P. Debenay(Ed.). IRD Cayenne, French Guiana.

LE BAIL, P.Y., P. KEITH & P.GERY. 1984a. Clé dedétermination des poissons continentaux etcôtiers de Guyane. Fascicule I. Bulletin de liai-son du Groupe de recherche de Guyane, Centrede recherches agronomiques des Antilles et dela Guyane-Institut national de la rechercheagronomique (6). 63 pp.

LE BAIL, P.Y, P. KEITH & P.GERY. 1984b. Clé de détermi-nation des poissons continentaux et côtiers deGuyane. Fascicule III. Bulletin de liaison duGroupe de recherche de Guyane, Centre de re-cherches agronomiques des Antilles et de laGuyane-Institut national de la recherche agro-nomique (8). 67 pp.

LE BAIL, P.Y, P. KEITH & P. PLANQUETTE. 2000. Atlas despoissons d’eau douce de Guyane. Tome 2, fas-cicule II: Siluriformes. Patrimoines naturels(M.N.H.N./S.P.N.), 43 (II): 307 pp.

LE COUR GRANDMAISON, S. 1995. Etude de la localisa-tion des nurseries de crevettes Penaeus subtilisen Guyane. Mém. ISTOM, 46 pp + annexes.

LE FLOCH, J. 1955. Esquisse de la structure hydrologi-que de l’Atlantique équatorial au large de laGuyane et de l’embouchure de l’Amazone. Bul-letin d’information du Comité Centrale d’Océa-nographie et d’Etude des Côtes, VII, 32 pp.

LE LOEUFF, P. & R. VON COSEL. 2000. Aperçus sur lamacrofaune benthique du plateau continental dela Guyane française (résultats de la campagneGREEN0, 16 au 20 avril 1999). Doc. Sci. Tech.Cent. IRD Bretagne, octobre 2000, Nº 86: 39 pp.

LINDNER, M.J. 1957. Survey of shrimp of Central andSouth America. Fish. Wild. Serv., Spec. Sci.Rep., 235, 166 pp.

LOINTIER, M. & M.T. PROST. 1986. Morphologie et hy-drologie d’un marais côtier équatorial: La sa-vane Sarcelle. Rapp. ORSTOM, 16 pp.

LONGHURST, A. R. 1998. Ecological Geography Of TheSea. Academic Press. 398 pp.

MADRID, V.M., J.Y. ALLER, R.C. ALLER & A.Y.CHISTOSERDOV. (2001). High prokaryote diversityand analysis of community structure in mobilemud deposits off French Guiana: identification

of two new bacterial candidate divisions. FEMSMicrob. Ecol. 37: 197-209.

MAIA DE OLIVEIRA, C. 2000. Le phytoplancton estuariende deux fleuves de Guyane Française (l’Iracouboet le Sinnamary): caractérisation du milieu,composition et diversité spécifique. Thèse deDoctorat (PhD), Université de Paris 6, 254 pp.

MARGALEF, R. & F. GONZÁLEZ/BERNÁLDEZ. 1969. Gruposde especies asociadas en el fitoplancton del marCaribe (NE Venezuela). Invest. Pesq., 33(1): 33-96.

MOGUEDET, G. 1977. Etude sédimentologique du plateaucontinental de la Guyane française. Rev. Trav.Inst. Pêches Marit., 41 (4): 389 - 402.

MOGUEDET, P., C. BENE & D. NERINI. 1995. Etude desressources en crevettes du plateau guyano-bré-silien. Etude de la variabilité du recrutement dela crevette Penaeus subtilis. Rapp. IFREMER,164 pp.

MORÁN, M.A., R.J. WICKS & R.E. HODSON. 1991. Exportof dissolved organic matter from a mangroveswamp ecosystem – evidence from natural fluo-rescence, dissolved lignin phenols, and bacte-rial production. Mar. Ecol. Prog. Ser., 76: 175-184.

MORICE, J. & N. WARLUZEL. 1968. La pêche à la crevettesur le plateau guyanais, les techniques améri-caines et l’analyse des captures. Rev. Trav. Inst.Pêches Marit., 32 (4) : 477-506.

NÉRINI, D. 1994. Elaboration d’un protocole d’analysesde données pour une typologie des peuplementsdémersaux du plateau continental Guyanais.Rapp. DEA Univ. Aix-Marseille II, IFREMER,60 pp.

ODUM W.E. & E.J. HEALD. (1972). Trophic analyses ofan estuarine mangrove community. Bull. Mar.Sci., 22, 671-738.

PAULMIER, G. 1993. Microplancton des eaux marines etsaumâtres de la Guyane et des Antilles Françai-ses. Editions de l’ORSTOM, Institut Français derecherche scientifique pour le développement encoopération, Collection Etudes et Thèses, Paris,436 pp.

PERODOU, J.B. 1994. Dynamique de la population devivaneau rouge (Lutjanus purpureus) deGuyane. Complémentarité des analyses globaleet structurale. Thèse Doct. Univ. Lille 1, 262 pp.

PLANQUETTE, P., P. KEITH & P.Y. LE BAIL. 1996. Atlas despoissons d’eau douce de Guyane (tome 1). Col-lection du patrimoine naturel, vol. 22. IEGB–M.N.H.N., INRA, CSP, Min. Env., Paris, 429 pp.

PRIMAVERA, J.H. 1997. Fish predation on mangrove as-sociated penaeids. The role of structure andsubstrate. Journal of Experimental Marine Bi-ology and Ecology, 215: 205-216.

PRIMAVERA, J.H. 1998. Mangrove as nurseries: ShrimpPopulations in Mangrove and Non-mangroveHabitats. Estuarine, Coastal and Shelf Science,46: 457-464.

PROST, M.T. 1989. Coastal dynamics and cheniers sands

Simposio.p65 05-04-04, 11:12 a.m.324

325

in French Guiana. In: Cheniers and CheniersPlains, PGEF Augustinus, ed. Marine Geology,Elsevier Science Publishers B.V., Amsterdam,90(4): 259-267.

PUJOS, M. & J.M. FROIDEFOND. 1995. Water masses andsuspended matter circulation on the FrenchGuiana continental shelf - Cont. Shelf Res., 15, 9:1157-1171.

PUYO, J. 1949. Poissons de la Guyane française. Faune del’empire Français. ORSOM, Paris, 12, 280 pp.

RAGOT, C. 1999. Structure des peuplements de nématodesde la mangrove de l’estuaire de Kaw (Guyane Fran-çaise) DEA (MSc.) Université de Paris VI. 30 pp.

RIVOT, E. 2000. Le vivaneau rouge (Lutjanus purpureus)dans la ZE de Guyane française. Bilan des con-naissances sur la biologie de l’espèce. analysede quelques aspects de la pêcherie vénézuélienne.Rapp. Ifremer. 100 pp.

RIVOT, E. A. CHARUAU., J. ROSE & J. ACHOUN. 2000. Lapêche du vivaneau rouge en Guyane. Un bilan del’exploitation sous le régime vénézuélien, destechniques de captures à adapter et à dévelpper.Contrat FIDOM/Ifremer. Rapp. Ifremer. 98 pp.

ROBERTSON, A.I. & N.C. DUKE. 1987. Mangrove as nurs-ery sites of fish and and crustaceans in mangroveand others near-shore habitats in tropical Aus-tralia. Mar. Biol. 96: 193-205.

ROJAS-BELTRÁN, R. 1984. Clé de détermination des pois-sons continentaux et côtiers de Guyane. Fasci-cule II - Siluriformes. Bulletin de liaison duGroupe de recherche de Guyane, Centre de re-cherches agronomiques des Antilles et de laGuyane – Institut national de la recherche agro-nomique, (7). 63 pp.

ROJAS-BELTRÁN, R. 1986. Rôle de la Guyane françaisecomme nourricerie des crustacés et des poissonsen Guyane. Le littoral guyanais. Fragilité de l’en-vironnement. Ier congrès régional de laSEPANGUY. Xème colloque SEPANRIT.SEPANGUY/SEPANRIT. 1985, Cayenne. 97-110.

ROSE, J. 1994. Compte rendu de la campagne‘‘RESUBGUY 4’’ (mai 1994) sur le plateau con-tinental de la Z.E.E. guyanaise. ContratF.E.D.E.R. DG XVI. Rapport IFREMER DRV-94RH/Cayenne, 59 pp.

ROSE, J. & J. ACHOUN. 1994. Compte rendu de la campa-gne ‘‘RESUBGUY 5’’ (octobre 1994) sur le pla-teau continental de la Z.E.E. guyanaise. ContratF.E.D.E.R. DG XVI. Rapport IFREMER DRV-95RH/Cayenne, 60 pp.

ROSSIGNOL, M. 1970. Projet d’élevage de crevettes enGuyane française. Rapp. ORSTOM, 6 pp.

ROSSIGNOL, M. 1972a. Etude d’un marais de la Guyanefrançaise: le marais Sarcelle - Biologie des cre-vettes: Penaeus aztecus subtilis (formes juvéni-les). Rapp. ORSTOM, 39 pp.

ROSSIGNOL, M. 1972b. Mariculture dans la règion deMana. Projet de création d’une station maricoleexpérimentale. Rapp. ORSTOM, 5 pp.

ROSSIGNOL, M. 1972c. Penaeus aztecus subtilis (PerezFarfante, 1967), dans le marais Sarcelle. Rapp.ORSTOM, 13 pp.

ROSSIGNOL, M. 1979. Milieu marin. In Atlas des départe-ments français d’outre-mer. IV. La Guyane,ORSTOM / CNRS.

SABORD, O. 1997. Opération SABORD 0 - Recueil de don-nées - Centre ORSTOM de Cayenne, Doc. ScientN°OP 26.

SYGUT, A. 2002. Productivité et adaptations des biofilmsphotosynthétiques colonisant les vasières litto-rales en zone tropicale (Guyane Française). Mé-moire de DEA (M.Sc.), Université de Bordeaux-I, 30 pp.

SYLVESTRE, F., D. GUIRAL & J.P. DEBENAY. 2002. Moderndiatol distribution in mangrove swamps from theKaw estuary (French Guiana). Submitted to Mar.Geol. (Ed. Baltzer).

TALVY, G., I. NOLIBOS & B. DE THOISY. 2001. Suivi de lapopulation de tortues luths (Dermochelyscoriacea) sur les plages de l’Est Guyanais. Reportassoc. Kwata / Sepanguy / DIREN Guyane.

TAKEDA, M. & T. OKUTANI. 1983. Crustaceans andmollusks trawled off Suriname and FrenchGuiana. JAMARC, Tokyo, 354 pp.

TEIXEIRA, C. & J. TUNDISI. 1967. Primary production andphytoplankton in equatorial waters. Bull. Mar.Sci., 17(4): 884-891.

TERNON, J.F., C. OUDOT, A. DESSIER & D. DIVERRES. 2000.A tropical sink for atmospheric CO

2 in the Atlan-

tic ocean: the role of the Amazon River discharge–J. Mar. Res., 68: 183-201.

TERNON, J.F., J.P. LEFEBVRE & D. GUIRAL. 2001. Physicaland chemical characterization of the FrenchGuiana continental shelf : spatial distribution andtemporal variability – Joint IAPSO/IABO Assem-bly: 2001 An Ocean Odyssey – 21-28 October2001 – Mar del Plata – Argentina.

TERNON, J.F., J.P. LEFEBVRE & D. GUIRAL. 2002. The in-fluence of the Amazonian waters over the FrenchGuiana continental shelf: the CHICO program.VI Workshop ECOLAB, 23-29 September 2002,Belém –PA, Brazil.

THIOLLAY, J.M. 1988. Les oiseaux menaces de Guyane.In: Livre rouge des oiseaux menacés des régionsfrançaises d’outre-mer. J.C . Thibault & I. Guyot(Eds.), CIPO, 61-80.

THOISY DE B., T. SPIEGELBERGER, S. ROUSSEAU, G. TALVY, I.VOGEL & J.C. VIE. (2002). Distribution, habitat,conservation status of the West Indian ManateeTrichechus manatus in French Guiana. (submit-ted).

TOSTAIN, O. 1986. Etude d’une succession terrestre enmilieu tropical: les relations entre la physiono-mie végétale et la structure du peuplement avienen mangrove guyanaise. La Terre et la Vie, 41:315-342.

VAQUER, A. 2000. Communautés planctoniques des va-sières et des mangroves: le phytoplancton. In Bi-lan des opérations de recherche 1999-2000 du


Simposio.p65 05-04-04, 11:12 a.m.325

326

Programme National Environnement Côtier -Chantier Guyane, dynamique des apports Ama-zoniens: 14-15. D. Guiral (ed.), IRD Cayenne,French Guiana.

VENAILLE, L. 1979. La pêcherie de crevettes pénéidés duplateau continental guayano-brésilien. Science etPêche, Bull. Inst. Pêches Marit., 297: 1-18.

VENDEVILLE, P. 1984. La pêcherie de crevettes tropicalesde Guyane française - Le problème des capturesaccessoires: estimation et implications. Thèse Doc.Ing. Inst. Polytech. Toulouse, 293 pp + annexes.

VENDEVILLE, P. 1990. Tropical shrimp fisheries: types offishing gears used and their selectivity. FAO Fish.Tech. Pap. , 261 Rev.1, 75 pp.

VENDEVILLE, P. 1993. Des nurseries estuariennes dePenaeus subtilis en Guyane. Mythe ou réalité?Quelques réflexions à partir de données re-cueillies sur les estuaires d’avril 1988 à juin1992. Centre ORSTOM de Cayenne, 56 pp.

VENDEVILLE, P. 1995. Reconnaissance des fonds de labande littorale du plateau continental guyanais-Campagne ‘‘Epaulard 94’’. Rapp. ORSTOM,111 pp.

VENDEVILLE, P. 2002. Estimation des paramètres de crois-sance des juvéniles de crevette Penaeus subtilisà partir de micro-cohortes journalières. In Halieu-tique: complexité et décision. 5éme Forumhalieumétrique Lorient, 26-28 juin 2001. Poster.Actes de colloques, recueil des résumés, Ifremered. 33, 74-75.

VENDEVILLE, P. & LHOMME F. 1997. Le cycle vital et le

recrutement de la crevette Penaeus subtilis enGuyane. Rap. ORSTOM, 282 pp.

VENDEVILLE, P., P. LE LOEUFF, R. VON COSEL & J. BOURGEAIS.2000. Éléments de structuration des communau-tés benthiques et démersales du plateau continen-tal de Guyane Française. Véme WorkshopECOLAB, Macapa, Brésil, 19– 24 novembre2000. Poster and abstract.

VENDEVILLE, P., P. LE LOEUFFX & R. VON COSEL. 2002.Eléments de structuration des communautés ben-thiques et démersales du plateau continental deGuyane française. Communication ColloquePNEC - 22-27 Januar 2002, Cayenne, France.

VENDEVILLE, P., P. L E LOEUFF & R. VON COSEL. 2002. Élé-ments de structuration des communautés benthi-ques et démersales du plateau continental deGuyane Française. 5éme Forum halieumétrique– Halieutique: complexité et décision. Lorient,26-28 juin 2001. Communication. Résumé à pa-raître dans la série ‘‘Actes de colloques’’ del’Ifremer.

VENKATESWARAN, K., M.E. DOLLHOPF, R. ALLER, T.E.STACKEBRAND & K.H. NEALSON. 1998. Shewanellaamazonensis sp. nov., a novel metal-reducing fac-ultative anaerobe from Amazonian shelf muds.Int. J. Syst. Bacteriol. 42, 965-972.

VIGNARD, C. 2001. Caractérisation et quantification desexportations de mangroves sous influence ama-zonienne. DEA Exploitation Durable des Ecosys-tèmes Littoraux (MSc.), University of La Ro-chelle, France, 40 pp.

Fecha de recepción: 05/05/03Fecha de aceptación: 121/09/03

Gayana 67(2), 2003

Simposio.p65 05-04-04, 11:12 a.m.326

MARINE BIODIVERSITY IN FRENCH GUIANA: ESTUARINE, … · 302 gayana 67(2): 302-326, 2003 issn 0717-652x marine biodiversity in french guiana: estuarine, coastal, and shelf ecosystems

Documents