1.Spatio-temporal distribution and anthropogenic mortality factors were investigated in loggerhead turtles (Caretta caretta) found stranded or floating in the waters around Italy. A total of 5938 records for the period 1980-2008 were analysed concerning loggerhead turtles measuring from 3.8 to 97 cm curved carapace length (mean: 48.3 cm).2.Results highlighted the following conservation issues: (i) in the study area, anthropogenic mortality is higher than natural mortality; (ii) interaction with fisheries is by far the most important anthropogenic mortality factor; (iii) longlines are an important mortality factor in the southern areas; (iv) trawlers are the cause of high numbers of dead strandings in the north Adriatic; (v) entanglement in ghost-gear or in other anthropogenic debris affects high numbers of turtles; and (vi) boat strikes are an important source of mortality in most areas but mostly in the warm seasons.3.Results also indicate that: (vii) the north Adriatic is the area with the highest turtle density; and (viii) the south Adriatic and to a lesser extent the surrounding areas of the north Adriatic and the Ionian, are important developmental areas for loggerhead turtles in the first years of life.4.Italy is in the centre of the Mediterranean Sea and borders major foraging areas for the loggerhead turtles in the region, and these results confirm previous concerns about the level of anthropogenic mortality in Italian waters. © 2010 John Wiley & Sons, Ltd
Sea turtle tagging carried out in Italy in the period 1981-2006 resulted in 125 re-encounters of loggerhead turtles (Caretta caretta) after a mean of 2.5 years, from different marine areas in the Mediterranean. At first finding, turtles ranged 25-83 cm of curved carapace length. Data were analyzed according to size, area, habitat type, season, in order to provide indication of movement patterns. When integrated with other information, results indicate that: (1) a part of turtles in the oceanic stage show a nomad behavior with movements among different oceanic areas; (2) another part show fidelity to an oceanic area; (3) turtles in the neritic stage show fidelity to neritic areas, and once settled to one area, change to other neritic areas is unlikely; (4) nomad oceanic turtles are significantly larger than sedentary ones, and also larger than turtles found in neritic areas; it is hypothesized that these could be Atlantic turtles that eventually leave the Mediterranean; (5) ecological transition from oceanic to neritic habitats occurs at a wide range of sizes, and some turtles may have a very brief oceanic stage; (6) turtles in the oceanic stage are more likely to recruit to neritic areas close to their oceanic areas than to distant ones; (7) part of turtles from some Mediterranean nesting beaches might frequent a relatively limited area range, including both oceanic and neritic areas; (8) in most of the Mediterranean, latitudinal seasonal migrations are unlikely. A general model of movement patterns of loggerhead turtles in the Mediterranean is proposed. © 2007 Springer-Verlag
SUMMARY: Survival probabilities of loggerhead sea turtles (Caretta caretta) are estimated for the first time in the Mediterranean by analysing 3254 tagging and 134 re-encounter data from this region. Most of these turtles were juveniles found at sea. Re-encounters were live resightings and dead recoveries and data were analysed with Barker's model, a modified version of the Cormack-Jolly-Seber model which can combine recapture, live resighting and dead recovery data. An annual survival probability of 0.73 (CI 95% = 0.67-0.78; n=3254) was obtained, and should be considered as a conservative estimate due to an unknown, though not negligible, tag loss rate. This study makes a preliminary estimate of the survival probabilities of in-water developmental stages for the Mediterranean population of endangered loggerhead sea turtles and provides the first insights into the magnitude of the suspected human-induced mortality in the region. The model used here for the first time on sea turtles could be used to obtain survival estimates from other data sets with few or no true recaptures but with other types of re-encounter data, which are a common output of tagging programmes involving these wide-ranging animals.Keywords: loggerhead sea turtle, survival, capture-mark-recapture, Mediterranean, Barker's model. RESUMEN: PROBABILIDADES DE SUPERVIVENCIA DE LA TORTUGA BOBA (CARETTA CARETTA) ESTIMADAS A PARTIR DE DATOS DE CAPTURA-MARCADO-RECAPTURA EN EL MAR MEDITERRÁNEO. -Las probabilidades de supervivencia de la tortuga boba (Caretta caretta) se han estimado por primera vez en el Mediterráneo analizando datos de 3254 marcajes y 134 recapturas en esta región. La mayoría de las tortugas eran juveniles encontrados en el mar. Las recapturas fueron reavistamientos de individuos vivos y recuperaciones de individuos muertos. Los datos se analizaron mediante el modelo de Baker, versión modificada del de Cormack-Jolly-Seber que puede combinar recaptura, reavistamientos de individuos vivos e individuos recuperados muertos. Se obtuvo una probabilidad de supervivencia anual de 0.73 (IC 95% = 0.67-0.78; n=3254), y debe considerarse como una estima conservativa debido a una desconocida, aunque no insignificante, tasa de perdida de marcados. Este estudio ofrece una estima preliminar de las probabilidades de supervivencia de los estadios de desarrollo "en el mar" para la población mediterránea amenazada de tortuga boba marina, y proporciona las primeras observaciones sobre la magnitud de la sospechada mortalidad inducida por el hombre en la región. El modelo, utilizado aquí por primera vez en tortugas marinas podría ser utilizado para obtener estimas de supervivencia a partir de otros datos con pocas o sin recapturas reales, pero con otros tipos de datos de recaptura frecuentemente producidos por programas de marcado de estos animales de amplia distribución.Palabras clave: tortuga boba, supervivencia, captura-marcado-recaptura, Mediterráneo, modelo de Barker.
The occurrence of barnacles and crabs on Caretta caretta specimens found in the waters around Italy was analysed. In the seas surrounding Italy balanomorph barnacles occur mainly on turtles frequenting shallow waters and crabs display a strong west-east gradient. Patterns of turtle distribution and movements are proposed. The abundance of turtle-specific barnacles may be dependent on, and so an indicator of, turtle density
The common chameleon Chamaeleochamaeleon is a Mediterranean lizard which has been introduced in many islands and its native origin in European countries is debated. Chameleons have been introduced in southern Italy, possibly from the Middle East and Tunisia. We conducted genetic analyses on mitochondrial DNA 16S gene on a larger sample. We observed a multiple origin for the Salento (Apulia, southern Italy) population, with individuals phylogenetically related to populations of North Africa and two areas in the Middle East. Some individuals may have been released before the 1950s and some others in the 1980s, improving the establishment success of this species.
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