Mablouke, C., Kolasinski, J., Potier, M., Cuvillier, A., Potin, G., Bigot, L., et al. (2013). Feeding habits and food partitioning between three commercial fish associated with artificial reefs in a tropical coastal environment. African Journal of Marine Science, 35, 323–334.
Résumé: At Reunion Island (south-western Indian Ocean), artificial reefs were submerged in 2003 in a bay and were soon colonised by fish, among which were the highly abundant commercial species Lutjanus kasmira, Priacanthus hamrur and Selar crumenophthalmus. The high concentration and diversity of fish around the artificial reefs is surprising, considering the low abundance of potential benthic prey. We investigated the diet and food partitioning between the aforementioned species using stomach content and stable isotope analyses (delta C-13, delta N-15). Priacanthus hamrur and S. crumenophthalmus fed on a larger prey diversity and showed significant overlap in their diets, with crustacean larvae the dominant prey. Fish larvae dominated L. kasmira's diet, and delta N-15 values confirmed the species' higher trophic level. Differences in delta C-13 between P. hamrur and S. crumenophthalmus indicated niche segregation, probably as a way to reduce competition, with P. hamrur being characterised by a smaller delta C-13 range and exhibiting a smaller isotopic niche than S. crumenophthalmus. There was a significant correlation between delta N-15 and fish standard length for the three species, suggesting that ontogeny partially explained the niche breadth. There was also a significant correlation between delta C-13 and length for L. kasmira, whereas individual specialisation was prevalent in S. crumenophthalmus.
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Nikolic, N., Jérôme, M., Fonteneau, A., Evano, H., & Verrez-Bagnis, V. (2016). Identification of skipjack tuna juveniles based on DNA control region sequences and potential spawning area around reunion island. Environmental Biology of Fishes, 99(2), 171–178.
Résumé: In this study, we confirmed that DNA control region can be used to identify potential spawning area from pelagic juveniles species. We used the mitochondrial DNA control region to identify tuna juveniles predated by common dolphinfish and sampled in surface waters around Reunion Island. These were skipjack juveniles at an early stage (small length and young age). The biological results confirmed the species identification based on DNA analysis. Catch data by longline reveal a higher number of skipjack from October to December around Reunion Island corresponding to the period of our skipjack juvenile sampling
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Trystram, C., Rogers, K. M., Soria, M., & Jaquemet, S. (2017). Feeding patterns of two sympatric shark predators in coastal ecosystems of an oceanic island. Can. J. Fish. Aquat. Sci., 74(2), 216–227.
Résumé: Stomach contents and stable carbon and nitrogen isotope analyses (delta C-13 and delta N-15) were used to investigate the trophic ecology of two apex predators, tiger sharks (Galeocerdo cuvier) and bull sharks (Carcharhinus leucas), from Reunion Island to describe their dietary habits at both the population and individual levels. In this oceanic island, the tiger and bull sharks were more piscivorous and teutophagous than noted in previous research from other localities. The delta C-13 values suggested that bull sharks depended on more neritic organic matter sources than tiger sharks, confirming a coastal habitat preference for bull sharks. Moreover, the total length of the bull shark influenced delta C-13 values, with smaller individuals being more coastal than larger individuals. All indicators suggest that there is a higher degree of similarity between individual tiger sharks compared with the more heterogeneous bull shark population, which is composed of individuals who specialize on different prey. These results suggest that the two species have different functions in these coastal habitats, and thus, they must be considered independently in terms of conservation and management.
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Zubia, M., De Clerck, O., Leliaert, F., Payri, C., Mattio, L., Vieira, C., et al. (2018). Diversity and assemblage structure of tropical marine flora on lava flows of different ages. Aquat. Bot., 144, 20–30.
Résumé: Recent volcanic lava flows extending into the ocean represent an ideal opportunity to study the long-term successional development of marine floral assemblages on the bare new substratum. We describe the floral assemblages of nine lava flows of different ages (prehistoric to 2007) at Piton de la Fournaise (Reunion Island, Indian Ocean) based on a survey of 37 stations. We identified 159 species including 148 macroalgae, 1 seagrass, and 10 cyanobacteria. Fifty-one of those represent new records for Reunion Island, and at least 9 taxa were identified as new to science. Recent lava flows were characterized by the dominance of ephemeral, opportunistic species, such as Pseudobryopsis hainanensis and Acrocladus dotyanus, while prehistoric lava flows were mainly characterized by perennial species, particularly Sargassum portiericuzum and Turbinaria ornata. A canonical correspondence analysis revealed that the environmental factor that most significantly correlated to the variation in floral assemblages was the distance to the most recent lava flow (2007). This factor was also highly correlated to coral cover. The composition of the different floral assemblages is discussed in relation to abiotic and biotic factors to explain ecological succession in a tropical environment.
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