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- Nesting Biology and conservation of the leatherback sea turtle (Dermochelys coriacea) in Espírito Santo State, Brazil, 1988-1989 to 2003-2004.(Chelonian Conservation and Biology, 2007-05-01) THOMÉ, J. C. A; BAPTISTOTTE, C; MOREIRA, L. M. P; SCALFONI, J. T; ALMEIDA, A. P; RIETH, D. B; BARATA, P. C. RIn Brazil, the only area where regular leatherback sea turtle (Dermochelys coriacea) nesting is known to occur is located on the northern coast of the state of Espı´rito Santo, around latitude 198S. In this study, we present the field methods used by Projeto TAMAR-IBAMA (the Brazilian Sea Turtle Conservation Program) in the state of Espı´rito Santo and analyze data on leatherback nesting from 1988–1989 to 2003–2004. In that period, 527 nests were observed in the study area. The annual number of nests varied between 6 (in 1993–1994) and 92 (in 2002–2003). Between 1995–1996 and 2003–2004, the annual number of nests increased at about 20.4% per year on average. Among the 527 clutches observed, 358 (67.9%) were left in situ, 50 (9.5%) were relocated to another spot on the beach, 88 (16.7%) were relocated to open-air beach hatcheries, and 31 clutches (5.9%) did not have their management decision recorded. Curved carapace length of nesting females was in the range of 139–182 cm (mean ¼ 159.8 cm). At present, there is no significant alteration of the nesting habitat in Espı´rito Santo, egg poaching has been reduced to very low levels, and there is no subsistence hunting for sea turtles of any species. The main challenges to leatherback conservation currently are the incidental capture in artisanal fisheries operating close to nesting beaches and in high seas fisheries operating in the South Atlantic, as well as activities related to the oil industry. An overview of Projeto TAMAR’s actions addressing current sea turtle conservation issues in the State of Espı´rito Santo is presented.
- Sea turtle feeding grounds of Brazil.(1998) MARCOVALDI, M. Â; SILVA, A. C. C. D. da; GALLO, B. M. G; BAPTISTOTTE, C; VIEITAS, C. F; BELLINI, C; LIA, E. H. S. M; CASTILHOS, J. C. de; THOMÉ, J. C. A; SANCHES, T. M
Item Reducing threats to turtles.(1999) MARCOVALDI, M. Â. G. dei; THOMÉ, J. C. A.; ECKERT, K. L; DONNELLY. M; ABREU-GROBOIS, F. A; BJORNDAL, K. AAround the world, the survival of seven species of sea turtle is threatened by a variety of man-induced factors, including the direct and indirect harvest of adults and juveniles (see Oravetz, this volume), threats to eggs and hatchlings (see Boulon, this volume; Mortimer, this volume), the degradation or loss of nesting habitat (see Witherington, this volume), and pollution of the seas (see Gibson and Smith, this vol ume). Perhaps no threat is as pervasive and devastating to declining populations as the persistent take of adult and juvenile turtles. The take continues, often in contravention of existing national and international legislation, largely because of familiar and ineffective "top-down" approaches to conservation, and a lack of grassroots support for or understanding of conservation initiatives. In response, conservation organizations and regulatory agencies alike are investing heavily in community-based conservation (see Frazier, this volume). Community-based conservation involves changing habits and outlooks, neither of which happens easily.- Educational campaign to reduce the impact of artificial light on sea turtle nesting beaches in Brazil.(2000) MARCOVALDI, M. Â; BELLINI, C; CASTILHOS, J. C de; SILVA, A. C. C. D. da; GALLO, B. M. G; BAPTISTOTTE, C.; LIMA, E. H. S. M; LIMA, E. P; SANCHES, T. M; THOMÉ, J; PATIRI, V. J. ASeveral important stages of reproduction by sea turtles normally take place at night, under the cover of darkness on beaches. Artificial lights on or near beaches often reduce the number of female sea turtles that emerge from the ocean to nest (Witherington, 1992; Ehrhart et al. 1996). When females do lay their eggs on beaches that are subject to artificial lighting, seafinding of the resultant hatchling turtles is often disrupted and they often go away from the sea (e.g. Philibosian, 1976; Peters and Verhoeven, 1994). Misoriented hatchlings face increased mortality from land predators, accidental trampling by people or vehicles, or desiccation following sunrise. Development of coastal areas, in the form of homes, hotels, industrial complexes, and recreational areas, leads to an increase of nighttime lighting. Unchecked lighting on beaches used by sea turtles can have serious impacts on nesting populations, and as such management of lighting on or near beaches is a priority for most sea turtle conservation programs.
- Reproductive biology and conservation status of the loggerhead sea turtle (Caretta caretta) in Espirito Santo State, Brazil.(2000) BAPTISTOTTE, C; THOMÉ, J. C. A; BJORNDAL, KThe reproductive biology of loggerheads nesting in Espírito Santo, Brazil, is evaluated for six nesting seasons (1991/1992 through 1996/1997), through data gathered by Projeto TAMAR-IBAMA, the Brazilian sea turtle conservation program. Mean curved carapace length of nesting females was 102.7 cm (n=198). Mean clutch size for clutches with more than 50 eggs was 119.7 (n=3664), and clutch size was significantly correlated with female body size. Management practices had significant effects on hatching success and incubation time. Mean hatching success of nests left in situ was 68.3% (n=879), of undepredated nests left in situ was 79.9% (n=751), and of nests moved to hatcheries and not depredated was 67.7% (n=2786). For nests moved to hatcheries, hatching success declined significantly with increasing time interval between oviposition and transfer to the hatchery. Mean incubation time was 59.5 days for nests left in situ (n=572) and 57.2 days for nests moved to hatcheries (n=2179). Incubation time declined significantly throughout the nesting season as temperatures increased; we conclude that sex ratio of hatchlings also shifts to more females as the season progresses. There was significant annual variation for all parameters. A short review of the conservation status of loggerheads in Espírito Santo State is also presented.
Item An overview of Projeto TAMAR-IBAMA'S activities in relation to the incidental capture of sea turtles in the Brazilian fisheries.(2002) THOMÉ, J. C. A; MARCOVALDI, M. A; MARCOVALDI DEI, G. G; BELLINI, C; GALLO, B. M. G; LIMA, E. H. S. M; SILVA DA, A. C. C. D; SALES, G.; BARATA, P. C. RProjeto TAMAR-IBAMA, the Brazilian Sea Turtle Conservation Program, is a network of 20 conservation stations that together protect over 1,000 km of Brazilian coastline on the mainland and on three oceanic islands. TAMAR was created in 1980, and initially focused its efforts on nesting beaches. Since 1990, a significant proportion of TAMAR's field activities have been focused on sea turtle feeding areas. Five species of sea turtles are found and nest in Brazil: the green turtle (Chelonia mydas, CM), the loggerhead (Caretta caretta, CC), the hawksbill (Eretmochelys imbricata, El), the olive ridley (Lepidochelys olivacea, LO) and the leatherback (Dermochelys coriacea, DC). Several nesting beaches and feeding areas are located near important fishing and/or shrimping grounds, where sizeable industrial fishing fleets operate. Moreover, artisanal fishing is a key livelihood for many coastal communities. Therefore, there is significant interaction between sea turtles and fishing gear around those areas, and the successful conservation of sea turtles by TAMAR must also involve actions to reduce incidental captures of sea turtles in fishing activities. Furthermore, since 1998 TAMAR has been collecting data on the level of sea turtle capture by the pelagic longline fishery off the Brazilian coast, which is a new frontier for conservation activities. Different actions have been implemented by TAMAR in each region in Brazil, depending on local conditions and available funds. Here, we present an overview of TAMAR's activities regarding the incidental capture of sea turtles by Brazilian fisheries.