44 research outputs found
Aproveitamento de alimentos de origem animal pela tartaruga-da-amazônia: Podocnemis expansa criada em cativeiro
Global research priorities for sea turtles : informing management and conservation in the 21st century
Over the past 3 decades, the status of sea turtles and the need for their protection to aid population recovery have increasingly captured the interest of government agencies, non-governmental organisations (NGOs) and the general public worldwide. This interest has been matched by increased research attention, focusing on a wide variety of topics relating to sea turtle biology and ecology, together with the interrelations of sea turtles with the physical and natural environments. Although sea turtles have been better studied than most other marine fauna, management actions and their evaluation are often hindered by the lack of data on turtle biology, human–turtle interactions, turtle population status and threats. In an effort to inform effective sea turtle conservation a list of priority research questions was assembled based on the opinions of 35 sea turtle researchers from 13 nations working in fields related to turtle biology and/or conservation. The combined experience of the contributing researchers spanned the globe as well as many relevant disciplines involved in conservation research. An initial list of more than 200 questions gathered from respondents was condensed into 20 metaquestions and classified under 5 categories: reproductive biology, biogeography, population ecology, threats and conservation strategies
Saturation of azimuthal anisotropy in Au + Au collisions at sqrt(s_NN) = 62 - 200 GeV
New measurements are presented for charged hadron azimuthal correlations at
mid-rapidity in Au+Au collisions at sqrt(s_NN) = 62.4 and 200 GeV. They are
compared to earlier measurements obtained at sqrt(s_NN) = 130 GeV and in Pb+Pb
collisions at sqrt(s_NN) = 17.2 GeV. Sizeable anisotropies are observed with
centrality and transverse momentum (p_T) dependence characteristic of elliptic
flow (v_2). For a broad range of centralities, the observed magnitudes and
trends of the differential anisotropy, v_2(p_T), change very little over the
collision energy range sqrt(s_NN) = 62-200 GeV, indicating saturation of the
excitation function for v_2 at these energies. Such a saturation may be
indicative of the dominance of a very soft equation of state for sqrt(s_NN) =
62-200 GeV.Comment: 432 authors, 7 pages text, 4 figures, REVTeX4. To be submitted to
Physical Review Letters. Plain text data tables for the points plotted in
figures for this and previous PHENIX publications are (or will be) publicly
available at http://www.phenix.bnl.gov/papers.htm
Direct Evidence for Gradual Ontogenetic Dietary Shift in the Green Turtle, Chelonia mydas
Energy expenditure of adult green turtles at their foraging grounds and during simulated oceanic migration
International audienceMeasuring the energy requirements of animals under natural conditions and determining how acquired energy is allocated to specific activities is a central theme in ecophysiology. Turtle reproductive output is fundamentally linked with their energy balance so a detailed understanding of marine turtle energy requirements during the different phases of their life cycle at sea is essential for their conservation. We used the non-invasive accelerometry technique to investigate the activity patterns and energy expenditure (EE) of adult green turtles (Chelonia mydas) foraging year-round at a seagrass meadow in Mayotte (n = 13) and during simulated oceanic migration (displacement from the nesting beach) off Mohéli (n = 1), in the south-western Indian Ocean. At the foraging site, turtles divided their days between foraging benthically on the shallow seagrass meadow during daylight hours and resting at greater depth on the inner side of the reef slope at night. Estimated oxygen consumption rates (sinline image) and daily energy expenditures (DEE) at the foraging site were low (sinline image during the day was 1·6 and 1·9 times the respective resting rate at night during the austral summer and winter, respectively), which is consistent with the requirement to build up substantial energy reserves at the foraging site, to sustain the energy-demanding breeding migration and reproduction. Dive duration (but not dive depth) at the foraging site shifted significantly with season (dive duration increased with declining water temperatures, Tw), while overall activity levels remained unchanged. In parallel with a significant seasonal decline in Tw (from 28·9 ± 0·1 °C to 25·3 ± 0·4 °C), there was a moderate (˜19%) but significant decline in DEE of turtles during the austral winter (901 ± 111 kJ day−1), when compared with the austral summer (1117 ± 66 kJ day−1). By contrast, the turtle moved continuously during simulated oceanic migration, conducting short/shallow dives in the day, which (predominately at night) were interspersed with longer and deeper ‘pelagic’ dives. Estimated oxygen consumption rates during a simulated migration (1·25 ± 0·16 mL O2 min−1 kg−0·83) were found to be significantly increased over the foraging condition, equal to ˜3 times the resting rate at night (0·42 ± 0·02 mL O2 min−1 kg−0·83), and daily energy expenditure amounted to 2327 ± 292 kJ day−1, underlining the tremendous energetic effort associated with breeding migration. Our study indicates that the accelerometry technique provides a new and promising opportunity to study marine turtle energy relations in great detail and under natural conditions
Covariates streamline age‐specific early life survival estimates of two chelonian species
Genetic composition, population structure and phylogeography of the loggerhead sea turtle: colonization hypothesis for the Brazilian rookeries
The loggerhead sea turtle, Caretta caretta, is the most common species of sea turtle nesting in Brazil and is listed as endangered by the IUCN. Our study characterizes the genetic structure of loggerheads in Brazil based on mitochondrial DNA control region variability and presents a hypothesis for the colonization of Brazilian rookeries. We analyzed 329 samples from Brazilian rookeries and an oceanic foraging ground, and we compared our results with previously published data for other loggerhead populations. Brazilian rookeries had four haplotypes, none of which have been reported for rookeries outside Brazil. Six haplotypes were found in the foraging aggregation. The presence of the CC-A4 haplotype at all sampled sites and the low nucleotide diversity suggest a common origin for all rookeries, with CC-A4 being the ancestral haplotype of the Brazilian populations. The occurrence of three haplotypes in the foraging aggregation that are known only from rookeries outside of Brazil is consistent with the transoceanic migratory behavior of loggerheads. Our results indicated that the colonization of Brazilian rookeries probably occurred from the southern USA stock. This recent colonization most likely followed a north to south route along the Brazilian coastline, influenced by the Brazilian warm current. Our results further suggest the existence of two genetic population units of loggerheads in Brazil and corroborate natal homing behavior in loggerheads
Ingestão de resíduos antropogênicos por tartarugas marinhas no litoral norte do estado da Bahia, Brasil Anthropogenic debris ingestion by sea turtles in the northern coast of Bahia, Brazil
Este trabalho descreve a presença de resíduos antropogênicos no trato digestório de tartarugas marinhas no Litoral Norte da Bahia, Brasil. Foram realizadas necropsias no trato digestório de 45 tartarugas marinhas encontradas mortas (Chelonia mydas n=36; Eretmochelys imbricata n=9), no período de janeiro de 2006 a outubro de 2007. Em 60% (27/45) das tartarugas necropsiadas foram encontrados resíduos, especialmente aqueles relacionados à atividade de pesca. Os resíduos encontravam-se ao longo de todo o trato gastrointestinal, com predominância no intestino grosso. A ingestão de resíduos pelas tartarugas marinhas do Litoral Norte da Bahia pode levar a debilidade e até mesmo provocar a morte destes animais.<br>This study investigates the presence of anthropogenic debris in the digestive tract of sea turtles in the Northern Coast of Bahia, Brazil. Necropsies were performed on 45 turtles, 36 green turtles (Chelonia mydas) and 9 hawksbills (Eretmochelys imbricata), found dead between january 2006 and october 2007. Debris was found in 60% of the animals, especially those related to fishing activities. Litter could be found throughout the entire gastrointestinal tract, but it was found predominantly in the large intestine (47.53%). The ingestion of debris by turtles from the Northern coast of Bahia may lead these animals to starvation, weakness and even death