TAMAR

URI permanente desta comunidadehttps://bdc.icmbio.gov.br/handle/cecav/1402

Centro Nacional de Pesquisa e Conservação de Tartarugas Marinhas e da Biodiversidade Marinha do Leste

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Resultados da Pesquisa

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    The Interplay of Homing and Dispersal in Green Turtles
    (2012-10-08) Naro-Maciel, E.; Bondioli, Ana Cristina Vigliar; Martin, Meredith; Almeida, A. P.; Baptistotte, C.; Bellini, C.; Marcovaldi, M. A.; Santos, A. J. B.; Amato, G.
    Current understanding of spatial ecology is insufficient in many threatened marine species, failing to provide a solid basis for conservation and management. To address this issue for globally endangered green turtles, we investigated their population distribution by sequencing a mitochondrial control region segment from the Rocas Atoll courtship area (n = 30 males) and four feeding grounds (FGs) in Brazil (n = 397), and compared our findings to published data (nnesting = 1205; nfeeding = 1587). At Rocas Atoll, the first Atlantic courtship area sequenced to date, we found males were differentiated from local juveniles but not from nesting females. In combination with tag data, this indicates possible male philopatry. The most common haplotypes detected at the study sites were CMA-08 and CMA-05, and significant temporal variation was not revealed. Although feeding grounds were differentiated overall, intra-regional structure was less pronounced. Ascension was the primary natal source of the study FGs, with Surinam and Trindade as secondary sources. The study clarified the primary connectivity between Trindade and Brazil. Possible linkages to African populations were considered, but there was insufficient resolution to con clusively determine this connection. The distribution of FG haplotype lineages was nonrandom and indicative of regional clustering. The study investigated impacts of population size, geographic distance, ocean currents, and juvenile natal homing on connectivity, addressed calls for increased genetic sampling in the southwestern Atlantic, and provided data important for conservation of globally endangered green turtles.
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    Coastal habitat degradation and green sea turtle diets in Southeastern Brazil
    (2011-06) Santos, R. G.; Martins, A. S; Farias, J. N; Horta, P. A.; Pinheiro, H. T.; Torezani, E.; Baptistotte, C.; Seminoff, J. A.; Balazs, G. H.; Work, T. M.
    To show the influence of coastal habitat degradation on the availability of food for green turtles (Chelonia mydas), we assessed the dietary preferences and macroalgae community at a feeding area in a highly urbanized region. The area showed low species richness and was classified as degraded. We examined stomach contents of 15 dead stranded turtles (CCL = 44.0 cm (SD 6.7 cm)). The diet was composed primarily of green algae Ulva spp. (83.6%). In contrast, the macroalgae community was dominated by the green alga Caulerpa mexicana. We found a selection for red algae, seagrass and Ulva spp., and avoidance for C. mexicana and brown alga Dictyopteris delicatula. The low diversity of available food items, possibly a result of environmental degradation, likely contributed to the low dietary diversity. The nutritional implications of this restricted diet are unclear.