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  • Fisheries Legislation in Seychelles

    Christy, L.C. (FAO, 1985-10)
  • Coral Bleaching in The Seychelles Impacts and Recommendations

    Goreau, T.J. (1998)
    Coral bleaching was assessed by underwater digital video in reefs at 14 locations around the Seychelles in late May 1998 as part of a continuing assessment of reef health with the Seychelles Marine Park Authority. Preliminary estimates are that around three quarters of all corals were recently dead, ranging from around 50% to over 90% at different sites. More precise measurements of mortality will be available later from detailed quantitative analysis of video records, but these will be underestimates of final mortality because many corals that were still partially alive at the time were still dying. The catastrophic mortality was due to excessively high sea surface temperatures, whose effect exceeds all previous threats to reefs to date. Strong international action to halt global warming is essential to prevent further recurrences of high temperature mortality in the future. Reef restoration efforts using mineral accretion technology to grow breakwaters and speed up the growth of corals will be essential to accelerate the recovery of lost environmental services such as reef fisheries, sand generation, tourism, and shore protection.
  • Distribution of commercially important fish species of Curieuse Marine National Park

    Pittman, S.J. (1997)
    Coral reef associated fisheries provide an important source of economically affordable animal protein for the populations of the Seychelles. In addition to satisfying the domestic market, demersal fishery supports a buoyant export market of fresh and frozen fish. Demersal nearshore fish are primarily caught from small boats, including pirogues and small boats with both outboard and inboard motors using a variety of gear types. Highest effort and catch rates are from outboards using handlining, traps and encircling gill nets. From 1990 to 1994, the catch from the small boat fishery of Praslin and La Digue includes a large range of demersal and pelagic species. Pelagics comprise a large proportion of the catch recorded at landings from small boats, including Carangidae (Jacks), Scombridae (Tuna/Mackerels) and Caesionidae (Fusiliers) and others. This accounted for some 47% of the catch from 1990 to 1994. The remaining component of the catch were species associated with coral reefs or have largely nearshore demersal life histories. These fish were largely the Lutjanidae (Snappers) and Lethrinidae (Emperors) 18.8%; the Siganidae (Rabbitfish), 15.2%; other trapfish including Acanthuridae (Surgeonfish), Scaridae (Parrotfish), Haemulidae (Sweetlips) and Mullidae (Goatfish) and others, 12.8%; Serranidae (Groupers), 3% and Sphyraenidae (Barracuda) caught mainly with handlines making up a very small proportion. Other significant catches included sharks, rays and octopus. These figures give some indication of the importance of particular target fish families to the artisanal fishery of Praslin. Further analysis shows a declining catch rate over 5 years from 54.2 kg/boat/day in 1990 to 36.03 kg/boat/day in 1994. Although these types of statistics are prone to large variations and a longer time scale study would be necessary to elucidate a trend. Most notably, landings of grouper have declined significantly from 16.8 MT in 1990 to 4.4 MT in 1994 in the Praslin and La Digue fishery. In this time statistics show a general increase in effort i.e. mean number of boats (SFA, 1990-94). Fisheries biologists in the Seychelles have suggested that the average catch of recent years is close to sustainable levels and that future exploitation must be closely monitored (Khadun, 1991). Efforts are being taken to encourage exploitation of fish stocks further offshore by improving the design and long-range efficiency of boats and their engines. This is a management strategy designed to relieve pressure on near shore populations and provide a refugia that will allow populations to increase to a more sustainable level and provide for a smaller scale nearshore artisanal fishery. Statistics show a general decrease in mean number of Pirogues operating per month (185 in 1985 to 64 in 1994) and increase in number of whalers (from 37 in 1985 to 91 in 1994) indicating an increased mechanisation of the Seychelles artisanal fishery fleet.
  • Coral reef fish assemblages of coralline and granitic habitats of Curieuse Marine National Park

    Pittman, S.J. (1997)
    Curieuse Marine National Park encompasses a diverse range of shallow water marine and brackish habitats including coralline fringing reefs, granitic boulder reefs, deep patch reefs, algal flats, seagrass meadows, intertidal rocky shore, sandy beach and mangrove habitat. Many of these shallow water habitats support an abundance of varied marine life, which in turn supports a burgeoning interest from tourist divers and snorkellers. Curieuse Marine National Park includes Curieuse Island and the surrounding waters including the channel between the island and the north-eastern coastline of Praslin. The designated boundary extends from Chevalier Point in the west to Pointe Zanguilles in the east up to high water mark, and includes the outlying islets of St. Pierre in the south-west. In 1971 a government White Paper states ‘’ It is intended that the reefs lying between Curieuse Island and Praslin should form an area to be designated as a Special Reserve, the object of which will be to protect the rich and varied reef community. The Commission is satisfied that traditional methods of fishing will not interfere unduly with the efficient management of this Special Reserve, and it is accordingly intended to permit fishing by traditional methods to continue in the area’’. Marine park designation began in 1979 when the area was declared a Marine National Park under the Curieuse Marine National Park (Designation) Order of 1979, S.I. 55, under the National Parks and Nature Conservancy Act, 1971. Additional areas, were designated shell reserves under Protection of shells regulations, S.I. 91, 1969 and The Conservation of Marine Shells Act,1981. Legislation permits no marine shell to be taken when such shells are on a reef, rock, bed of a lagoon or the sea or sea floor, within 400 m from the low water mark. There are a number of specifically exempted species, and the possession of explosives within such a reserve is prohibited. The total area is some 1370 ha including 283 ha of land (Curieuse) to 30 m below sea-level. The area is mostly government owned with some land areas such as the land around Anse Petit Cour privately owned.
  • The Reefs of the Granitic Islands of the Seychelles

    Klaus, R.; Turner, J.; Engelhardt, U. (2000)
    The status of coral reefs in the granitic islands of the Seychelles archipelago has been assessed by two independent surveys following the mass mortality caused by the 1997/98 bleaching event. Engelhardt (2000), working in collaboration with the Seychelles Department of Conservation surveyed 15 sites located mainly on the north west coast of Mahe during November and December 1999. During January 2000, Turner, Klaus, Hardman and West, working in collaboration with the Seychelles Marine Park Authority, surveyed 46 reef sites mainly to the east of Mahe, including Ste Anne, Ile Moyenne, Ile Cerf, Cousine, Praslin, Curieuse, La Digue, Grand Soeur and Felicite. Reefs around the granitic islands are shallow and rarely exceed 15 m depth. Both surveys aimed to assess reef structure over the full depth range, with corals identified to genus and species where possible, and assessed reef recovery by recording new colonies believed to have established since the bleaching event.
  • The Status of the Aldabra Atoll Coral Reefs and Fishes Following the 1998 Coral Bleaching Event

    Teleki, Kristian; Downing, N.; Stobart, B.; Buckley, R. (2000)
    It is important to establish benchmark reef locations that are remote from centres of human activity and free from anthropogenic disturbances, against which human impacts elsewhere can be assessed and rates of recovery evaluated. Aldabra Atoll in the southern Seychelles, is free of anthropogenic disturbances and an ideal location in which to study reefs and adjacent ecosystems. It has further significance with it being in the middle of a region which has been classified as having a number of reefs at high risk (Bryant et al., 1998) and has been designated as a UNESCO World Heritage site.
  • Reef Systems of the Islands of the Southern Seychelles

    Spencer, Tom; Teleki, Kristian (2001)
    There are 74 coralline islands in the Southern Seychelles, from which representative reefs have been selected for this report, comprising an atoll (Alphonse), a raised platform island (St Pierre), a carbonate bank (Providence-Cerf) and a drowned atoll (Cöetivy) (Figure 1). Aldabra Atoll is treated in a separate section in this publication (see Teleki et al., this volume). Qualitative observations of reef morphology, coral community composition and reef health in the southern Seychelles were made between March and May 1998 (Southern Seychelles Atoll Research Programme - SSARP), February and March 1999 (Thalassi/Shoals of Capricorn Expedition) and November 1999 (Aldabra Marine Programme – AMP). These observations were supplemented by quantitative descriptions of coral communities at 48 sites at four study locations. Twenty-five meter long transects were set out at water depths, where possible, of 5 m, 10 m, 15 m and 20 m. Transects were surveyed using both a line point intercept method and digital videographic imagery which was subsequently analysed using point sampling to generate estimates of benthic cover. Digital stills of individual coral species were obtained from each site for taxonomic inventory purposes.
  • Do recent data from the Seychelles Islands alter the conclusions of the NRC Report on the toxicological effects of methylmercury?

    Stern, A.H.; Jacobson, J.L.; Ryan, L.; Burke, T.A. (2004-01-30)
    Environmental Health: A Global Access Science Source, 3:2
    In 2000, the National Research Council (NRC), an arm of the National Academy of Sciences, released a report entitled, "Toxicological Effects of Methylmercury." The overall conclusion of that report was that, at levels of exposure in some fish- and marine mammal-consuming communities (including those in the Faroe Islands and New Zealand), subtle but significant adverse effects on neuropsychological development were occurring as a result of in utero exposure. Since the release of that report, there has been continuing discussion of the public health relevance of current levels of exposure to Methylmercury. Much of this discussion has been linked to the release of the most recent longitudinal update of the Seychelles Island study. It has recently been posited that these findings supercede those of the NRC committee, and that based on the Seychelles findings, there is little or no risk of adverse neurodevelopmental effects at current levels of exposure. In this commentary, members of the NRC committee address the conclusions from the NRC report in light of the recent Seychelles data. We conclude that no evidence has emerged since the publication of the NRC report that alters the findings of that report.
  • Coral reef fish assemblages of Baie Ternay National Marine Park and Baie Beau Vallon, Mahé, Seychelles

    Pittman, S.J. (1995-11)
    The two most important foreign exchange earning activities in the Seychelles are tourism and fisheries and therefore, the coastal areas and their management are of the greatest importance to the Seychelles government (Khadun, 1991). In recent years government policy has encouraged marine conservation (Procter, 1970; 1984-1989 National Development Plan) and is part way to fulfilling the programme outlined in the Environmental Management Plan of the Seychelles (EMPS, 1990-2000). To date, five marine areas have been designated as national marine parks covering about 23 000 ha with several more proposed parks and protected areas. However, financial constraints, a deficit of qualified personnel, lack of boundary delimitation, inadequate legislation and increasing development has meant that the parks have never been managed or protected adequately. Increased tourism and poaching is leading to damage to reef integrity and decreasing aesthetic appeal due to anchor drops, illegal collecting and fishing, land based pollution and sedimentation as well as increased littering (EMPS, 1990-2000 and pers. obs.). Many natural communities worldwide are experiencing large and fundamental changes in structure, often as a result of anthropogenic activities and often manifesting themselves as a decrease in diversity (Sebens, 1994). The difficulties of monitoring reef ‘health’ through indicator species or species distributions is well documented. Problems usually arise due to a lack of baseline data, lack of fixed location monitoring sites, variation in methodology and often unsuitable comparative data. It is also particularly difficult to isolate some early stages or low level impacts, from normal variation. An important initial phase of any effective program of action is the collection and interpretation of baseline data on the distribution and richness of fish and invertebrate communities and assessments of the state of the reef habitat. A wealth of studies have examined distributions of reef-associated fish throughout the tropics yet remarkably few studies have sought to quantify the reef fish communities of the granitic Seychelles. It has become increasingly evident that assemblages of reef fish and their physical and biological environments vary greatly among habitat patches at all spatial scales (Bouchon-Navaro, 1980, 1981; Sale, 1980a; Harmelin-Vivien, 1981; Bouchon-Navaro and Harmelin-Vivien, 1981; Williams, 1982, 1983a, 1983b; Galzin et al, 1979, 1983, 1990, 1994; Bell and Galzin, 1984; Russ, 1984a,b; Williams et al., 1986a; Doherty and Williams, 1988a; Thresher, 1991; Roberts et al, 1992; TMRU, 1993, 1994, 1995; Caley, 1995a,b; and others). Generalisations concerning population dynamics and management strategies for fish communities must take into account spatial and temporal variation in diversity and abundance. Many factors have been attributed to variation in fish assemblages on coral reefs, including niche diversification, spatial and temporal variation in recruitment, food availability, live coral cover, substratum type, current flow, water quality, exposure to wave action, topographic complexity, availability of hiding places, and human extraction. Clearly, comparisons between reefs and within reefs must include information on a variety of influencing factors in any attempt to describe and explain species distributions. Analysis of data should provide meaningful baseline information from which to effectively manage, an increasingly important natural resource. Most published work on reef-associated fish in the Seychelles region has focused on taxonomy, with intensive collecting for museum curation. Smith and Smith (1969) and Randall and van Egmond (1994) give good historical accounts and bibliographies of this work to date. A brief account is given below. During French colonialism from 1743 until 1810, specimens were collected and sent to Paris, where they joined the collections to be later studied by Cuvier and Valenciennes and contributed to those species published in the volumes of Histoire Naturelle des Poissons in the early 19th century. The first species list of Seychelles fishes was compiled by Col. R.L. Playfair (1867) who recorded 211 species followed by Mobius (1880) and Mobius and Peters (1883) who listed fishes from Mauritius and Seychelles, Regan (1907) from Stanley Gardiner`s collecting in the Indian Ocean, and various resident collectors. Most notable is the work of Smith and Smith whose extensive collecting in 1954 culminated in the publication of Fishes of Seychelles in 1963 and a revised 2nd edition in 1969. 475 species were added to the known species list, with some 775 species described and illustrated from the Seychelles proper, (northern islands) including many pelagic and deep water species. However, many of these species have been regrouped since and some (particularly Labridae and Scaridae) are in fact juveniles or dichromatic variants of the same species. More recently expeditions to Seychelles (Seychelles Coral Reef Expedition, 1972, Catford, 1972 and RV Tyro Netherlands Indian Ocean Programme, 1992-3, van der Land, 1994) have added to the record of fishes. Polunin (1984) lists a further 79 records for the wider Seychelles and Randall and van Egmond (1994) a further 108 new records. Often overlooked and uncited in any of the recent literature and possibly the first paper on habitat and reef fish distributions in the Seychelles is by Landini and Sorbini (1988) on the ichthyofauna of back reef zones and sea grass environments of Mahe and Praslin. Artisanal fisheries and coral reef community structure in the Seychelles is currently an area of increasing interest and artisanal reef fisheries impact studies by Jennings et al. (1996a, 1996b) have compared fish community structure in areas exposed to varying fishing intensities.
  • Coral Recovery From Bleaching in Seychelles

    Goreau, T.J. (GCRA, 1998-12-12)
    Digital video transects were filmed at nine coral reef locations around Mahe in March 1997, and at 14 locations including additional sites in Curieuse, Coco, La Digue, and Cousin in May1998 as part of at he Seychelles Marine Park Authority Monitoring program. This report describes preliminary observations made at 16 locations, including most of the previous sites and some new ones during early December1998. The first series of videos recorded the condition of the coral reef prior to the impact of coral bleaching, the second recorded conditions during the intense coral bleaching event of early 1998, and the current observations record conditions in the aftermath of the event, allowing the first accurate estimates of overall mortality and survivorship and of the differences in them between habitats. Due to lack of time and bad weather it was unfortunately not possible to re-film the sites around Curieuse, Cousin, and La Digue, however some new sites were examined near Mahe, and additional sites in the Amirantes will be covered in a separate report. This report contains preliminary field notes, and much more detailed quantitative information on coral species abundance, survival, and mortality will be available after the digital videos are analyzed. All three series of observations will be contrasted in more detail in a longer study to be published in a forthcoming IUCN volume of bleaching studies from around the world to be edited by T. Goreau, T.McClanahan, andR. Ormond.
  • Coral Recovery From Bleaching in Alphonse and Bijoutier

    Goreau, T.J. (GCRA, 1998-12)
    Global Coral Reef Alliance
    Mortality of corals in the Alphonse group following the 1998 bleaching event was somewhat less than in the high islands of the Mahegroup. Overall mortality of corals on fore reef slopes was around 90%in shallow water and around 70-80% on vertical slopes, in comparison to values around 95 and 99% in the inner islands. Although mortality of Acroporas was nearly total, several small surviving colonies were found at a range of depths including very shallow seagrasses. In contrast with the high islands, many partially surviving Pocilloporaverrucosa colonies were found. The major survivors were Helioporacoerula (rare in the inner islands), Porites head species (probablylutea), Porites cylindrica,Porites nigrescens, Astreoporamyriophthalma, Hydnophora microconos, and Favid corals. Coral diversity was lower than in the high islands and no iploastreas or Gonioporas were seen in the Alphonse group, although these were found at every site in the high islands. Survival of corals was very high, roughly 80%, inside the Alphonse lagoon, also higher than equivalent habitats in the Inner Islands. Although the tiny human population is insufficient to cause eutrophication, evidence of high natural nutrient sources was seen. Strong upwelling is the cause of significant algae abundance in deep waters, while the lagoons at Alphonse and Saint Francois (but not Bijoutier, which lacks a lagoon) have green water which affects surrounding reefs and promotes algae growth, apparently as the result of recycling of nutrients from sea grass decomposition. Areas not affected by such sources, such as Bijoutier, are predominantly overgrown by encrusting pink calcareous algae, creating the surfaces needed for new coral settlement.