Emmanuel Tessier

University of La Réunion, Saint-Denis, Réunion, Reunion

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Publications (10)15.23 Total impact

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    ABSTRACT: A b s t r a c t An annotated checklist of the fish species of La Réunion (southwestern Indian Ocean) comprises a total of 984 species in 164 families (including 16 species which are not native). 65 species (plus 16 introduced) occur in fresh-water, with the Gobiidae as the largest freshwater fish family. 165 species (plus 16 introduced) live in transitional waters. In marine habitats, 965 species (plus two introduced) are found, with the Labridae, Serranidae and Gobiidae being the largest families; 56.7 % of these species live in shallow coral reefs, 33.7 % inside the fringing reef, 28.0 % in shallow rocky reefs, 16.8 % on sand bottoms, 14.0 % in deep reefs, 11.9 % on the reef flat, and 11.1 % in estuaries. 63 species are first records for Réunion. Zoogeographically, 65 % of the fish fauna have a widespread Indo-Pacific distribution, while only 2.6 % are Mascarene endemics, and 0.7 % Réunion endemics. The classification of the following species is changed in the present paper: Anguilla labiata (Peters, 1852) [pre-viously A. bengalensis labiata]; Microphis millepunctatus (Kaup, 1856) [previously M. brachyurus millepunctatus]; Epinephelus oceanicus (Lacepède, 1802) [previously E. fasciatus (non Forsskål in Niebuhr, 1775)]; Ostorhinchus fasciatus (White, 1790) [previously Apogon fasciatus]; Mulloidichthys auriflamma (Forsskål in Niebuhr, 1775) [previously Mulloidichthys vanicolensis (non Valenciennes in Cuvier & Valenciennes, 1831)]; Stegastes luteobrun-neus (Smith, 1960) [previously S. fasciolatus (non Ogilby, 1889)]. Due to rapid economic and agricultural development and population growth during the past centuries and de-cades, the native fish fauna of Réunion is now highly threatened and needs urgent political action to ensure its conservation. The marine fish species of Réunion are threatened by eutrophication/pollution, by overfishing and poaching, by marine aquaculture, and by construction along the shore; additional regional threats include long-ranging marine eutrophication and pollution, destruction of coastal areas, marine acidification, and global warm-ing. Freshwater habitats are threatened by eutrophication and pollution, by the construction of dams, weirs and barrages, water abstraction for irrigation, gravel extraction from river beds, some special fisheries techniques (like 'bichique' fishing, including strong seasonal poaching pressure), introduction of exotic species, and aquaculture. Out of a total of 968 native fish species of Réunion, 374 species (39.2 %) are on the Red List, with 18 species regionally extinct (1.9 %), 27 species critically endangered (2.8 %), 115 species endangered (11.9 %), 160 species vulnerable (16.6 %), 32 species near threatened (3.3 %), and 26 species threatened migrants (2.7 %). An additional 575 species are data deficient (59.4 %). 16 species have been introduced and are thus not native; they were not evaluated for the Red List. Only the remaining 10 species in Réunion are not threatened. In addition to the Red List, a list of taxa proposed for the Annexes II, IV and/or V of the EU Habitats Directive is presented. A set of measures for the conservation of the Réunion fish fauna is proposed. K e y w o r d s : Checklist, Red List, threatened and declining species, Pisces, marine, freshwater, transitional waters, new records, Réunion, southwestern Indian Ocean, IUCN criteria, EU Habitats Directive, EU Water Frame-work Directive. Z u s a m m e n f a s s u n g Die Checkliste der Fische von Réunion (südwestlicher Indischer Ozean) enthält 984 Arten in 164 Familien (ein-schließlich 16 nicht einheimischen Arten). 65 Arten (sowie 16 eingeführte) leben im Süßwasser, mit den Gobiidae als artenreichster Süßwasserfischfamilie. 165 Arten (sowie 16 eingeführte) leben in Übergangsgewässern (Brack-wasser). Im Meer werden 965 Arten (sowie eine eingeführte) gefunden, mit den Labridae, Serranidae und Gobiidae als artenreichste Familien. 56,7 % dieser Arten leben in seichten Korallenriffen, 33,7 % innerhalb des Saumriffes, 28,0 % in seichten Felsriffen, 16,8 % auf Sandböden, 14,0 % in tiefen Riffen, 11,9 % auf der Riffplattform, und 11,1 % in Ästuaren. 63 Arten werden zum ersten Mal in Réunion gefunden. Zoogeographisch haben 65 % der Fisch-arten eine großräumige indo-pazifische Verbreitung, während nur 2,6 % endemisch bei den Maskarenen und 0,7 % endemisch in Réunion sind. Die Klassifikation der folgenden Arten wird in der vorliegenden Arbeit geändert: Anguilla labiata (Peters, 1852) [bisher A. bengalensis labiata]; Microphis millepunctatus (Kaup, 1856) [bisher M. brachyurus millepuncta-tus]; Epinephelus oceanicus (Lacepède, 1802) [bisher E. fasciatus (non Forsskål in Niebuhr, 1775)]; Ostorhinchus fasciatus (White, 1790) [bisher Apogon fasciatus]; Mulloidichthys auriflamma (Forsskål in Niebuhr, 1775) [bisher Mulloidichthys vanicolensis (non Valenciennes in Cuvier & Valenciennes, 1831)]; Stegastes luteobrunneus (Smith, 1960) [bisher S. fasciolatus (non Ogilby, 1889)]. Durch die schnelle ökonomische und landwirtschaftliche Entwicklung und das starke Bevölkerungswachstum in Réunion während der letzten Jahrhunderte und Jahrzehnte ist die Fischfauna inzwischen stark gefährdet und benötigt dringend politische Maßnahmen, um erhalten zu bleiben. Die marine Fischfauna wird durch Verschmut-2 sTuTTgaRTeR beiTRäge zuR naTuRkunde a Neue Serie 2
  • 12th International Coral Reef Symposium, Australia; 01/2012
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    ABSTRACT: The objectives of marine protected areas (MPA), such as Reunion’s Marine Reserve founded in 2007, are (i) protect habitats (ecosystems) and resources (biodiversity) from increasing pressure due to a major urban, economic and recreational development; ii) manage uses and conflicts between traditional fisheries, spear-fishing, diving and recreational activities inside the coastal zone. These goals necessitate monitoring tools such as indicators and diagnostics. The PAMPA programme involves seven MPA including the Natural Marine Reserve of La Reunion (RNMR). It aims for each site to identify and validate indicators according to management objectives and group them in a MPA performance dashboard. This panel will help to visualize temporal trends and define threshold values between different levels of MPA performance. The data used in the analysis are related to natural resources and biodiversity (corals, fish, habitats), uses (traditional fishing, recreational and commercial) and governance (administrative and financial data, users perception surveys). The assemblage of data involved the definition of a common species classification scheme, the compilation of geographic distribution data and the harmonisation of databases to allow cross-analysis. For resources and biodiversity data, the long-term monitoring settled up since 1998 (GCRMN) had allowed testing indicators and the implementation of a dashboard with trends, thresholds and performance classes for each site. For uses and governance data, as monitoring and surveys are recent, little information were implemented on the dashboard. But the approach developed on the program had allowed to target the relevant indicators and to initiate a long-term monitoring necessary to complete the dashboard that will allow monitoring of various performance indicators over time. Continuous cooperation between managers and scientists throughout the project, around RNMR and with other MPA sites, allowed a permanent transfer of the program’s progress towards managers. They were able to integrate the results of the programme to define the framework of the RNMR management plan (2011-2015).
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    ABSTRACT: Difficulties in scaling up theoretical and experimental results have raised controversy over the consequences of biodiversity loss for the functioning of natural ecosystems. Using a global survey of reef fish assemblages, we show that in contrast to previous theoretical and experimental studies, ecosystem functioning (as measured by standing biomass) scales in a non-saturating manner with biodiversity (as measured by species and functional richness) in this ecosystem. Our field study also shows a significant and negative interaction between human population density and biodiversity on ecosystem functioning (i.e., for the same human density there were larger reductions in standing biomass at more diverse reefs). Human effects were found to be related to fishing, coastal development, and land use stressors, and currently affect over 75% of the world's coral reefs. Our results indicate that the consequences of biodiversity loss in coral reefs have been considerably underestimated based on existing knowledge and that reef fish assemblages, particularly the most diverse, are greatly vulnerable to the expansion and intensity of anthropogenic stressors in coastal areas.
    PLoS Biology 04/2011; 9(4):e1000606. · 12.69 Impact Factor
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    Stuttgarter Beiträge zur Naturkunde A Neue Serie. 01/2009; 2:1-168.
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    ABSTRACT: Coral reefs of Reunion Island in 2007 : status report and monitoring network.— Reunion Island is 2500 km2 and belongs to the outermost regions of European Union (EU). The population attained 774 600 inhabitants in 2004 with 25 % living in the western part of the island, 80 % in the littoral zone (called « bas »). The gross domestic product (GDP) per capita is less than 50 % of the mean index of the EU. The rate of unemployment was of 33 % in 2004. Coral reef ecosystems extend over 12 km2 along 25 km of the west and south coasts of the island. In addition to the natural influence of climatic events (global change) coral reef ecosystems are impacted by direct and indirect influence of the increase of human population. Direct impacts are mainly due to human overfrequenting of reef flats and overfishing. Indirect impacts are due to urbanization and to industrial, agricultural and urban pollutions. The competence in marine environment is assumed by an administration (Direction Régionale de l’Environnement). Researches on coral reefs are run by research institutes and NGO. The first coral reef monitoring network was set up in 1998 on the Saint-Gilles/La Saline reef. Since then, it was extended to the three other main reef units (Saint Leu, Etang Salé, Saint Pierre) and the data are gathered for 2001 by ecoguards of the association « Parc Marin de la Réunion », with the partnership of the university (Laboratoire d’Ecologie Marine). Data are stored in a database (CORE MO) and analysed by ARVA M (Agence pour la Recherche et la Valorisation Marine). The operation is funded both by the state administration and a local administration (Conseil Régional). Reunion Island is a part of the South-West Indian Ocean node of the Global Coral Reef Monitoring Network (GCR MN). It is regularly involved in the redaction of the « S tatus of coral reefs of the world ». At the same time another network involving stakeholders is built using the Reef chek protocole. At the present time, coral reefs of Reunion Island are deteriorated. If the density of the targeted species of fish has not changed since 1999, the surface of live corals has shown a significant decrease on half of the 14 stations, particularly after two bleaching events in 2003 and 2004. The various negative impacts due to human activities contribute to weaken these ecosystems and to decrease their resilience. Hence, they are less and less able to resist exceptional climatic events (cyclones, swells) and the bad impacts of global change (bleaching). To face to the stake of long term development, 75 % of the reef units of the island are protected since February 2007 by the status of « R éserve Naturelle Nationale Marine » (35 km2 of marine protected area).
    Revue d Ecologie 01/2008; 63:85-102. · 0.28 Impact Factor
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    ABSTRACT: Artificial coastal reefs were initially installed off Reunion Island (SW Indian Ocean) in order to attract and catch small pelagic fish of economic importance for the local fishery. These artificial reefs also attract a high density of juvenile coral reef fish, especially after recruitment. Because of high species richness and density, a suitable method of evaluating diversity and abundance in such assemblages is needed. An experiment was conducted in situ for 1 year in order to test which of the two visual techniques, slate or video recording, would be the most suitable for sampling artificial reefs. For the quantitative study, a rope framework (four belt transects each measuring 24×3 m) was used to ease the movement of the divers. To avoid bias due to time variations, the study was conducted under limited time in situ. The advantages and disadvantages of the two techniques regarding the accuracy of qualitative and quantitative results are discussed. The qualitative study results show that the slate technique is the most accurate one for determining species richness. In the quantitative study, factors such as species characteristics (ecological type), attractiveness (relationship between fish and diver) and abundance of fish communities around the artificial reefs appear to influence our results on the comparison of the two techniques. Of 13 ‘permanent’ (observed in more than 75% of dives) species, 6 returned a similar frequency of detection by slate and video (Lutjanus kasmira, Lutjanus bengalensis, Priacanthus hamrur, Chaetodon kleinii, Heniochus diphreutes, Mulloides vanicolensis); these were then selected for comparison of the techniques using quantitative data. The correlation between video and slate census results is high, but, in comparison with the slate census, the video census underestimates abundance, especially for low values. A corrected index is proposed to remedy this underestimation; it could be used for video surveys conducted on species responding well to video detection (as below).
    Journal of Experimental Marine Biology and Ecology 02/2005; 315(1):17–30. · 2.26 Impact Factor
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    ABSTRACT: The ichtyofauna of Geyser and Zelee coral banks (north of Mozambique canal) was investigated in 1996, this work being the first quantitative study on this area. Quantitative data were collected on 11 stations (mean depth 18 m) by visual observations along 50 m transect, widened to 2 m for small sedentary species, and to 5 m for commercial species with a large action range. The main descriptors of the fish communities (species richness, abundance per species) and the trophic structure (omnivorous, herbivorous, carnivorous, browsers of sessile invertebrates) were described and analysed.A total of 294 fish species, belonging to 43 families were recorded. The species richness varied from 45 to 83 species / station, and the abundance, from 292 to 1322 individuals / 100 m(2), the lower values being recorded on the inner slope and the higher ones on the outer slope. In terms of number of individuals, diurnal planktivores were highly represented at all sites (mean 63.7%). Pomacentridae and Caesionidae were the most abundant families, damselfishes being mainly represented by Chromis ternatensis (mean 73 ind., max, 148 ind. 100 m(2)), C. dimidiata (mean 33 ind., max. 151 ind. / 100 m(2)) and Dascyllus carneus (mean 38 ind., max. 92 ind. 100 m(2)), and fusiliers by Pterocaesio chrysozona (mean 19 ind., max. 128 ind. / 100 m(2)), P. tile (mean 12 ind., max. 38 ind. / 100 m(2)) and Caesio teres (mean 6 ind., max. 32 ind. / 100 m(2)). The high values recorded showed that small and isolated coral banks can support relatively rich fish faunas and substantial populations of individuals. This result may be explained by different factors such as the oceanographic circulation favourable to a localised enrichment of nutrients from surface water, the low human impact, a good coral cover and a high degree of self-recruitment associated with regional recruitment. Nevertheless, the main commercial species such as Lutjanus bohar and Variola louti, observed at each station, were represented at a low density (mean 0.8 ind., max. 6 ind. / 100 m(2) and mean 0.2 ind., max. 0.8 ind. / 100 m(2) respectively). This result may be due to the exploitation of these coral banks between 1990 and 1992, which was interrupted following the fast decreasing output.Such an experience shows us the fragility of these small coral banks and the necessity to establish a rational management of the resource.
    Cybium (0399-0974) (Soc Francaise D Ichtyologie), 2002 , Vol. 26 , N. 1 , P. 11-26. 01/2002;