Naslov
Sex ratios of juvenile loggerhead sea turtles Caretta caretta in the Mediterranean Sea

Autori
Casale, Paolo ; Lazar, Bojan ; Pont, Sara ; Tomas, Jesus ; Zizzo, Nicola ; Badillo, Javier ; Di Summa, Aldo ; Freggi, Daniela ; Lacković, Gordana ; Raga, Juan Antonio ; Rositani, Lucio ; Tvrtković, Nikola

Izvornik
Marine Ecology Progress Series (0171-8630) 324 (2006); 281-285

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
sex ratio; Caretta caretta; Mediterranean; juvenile sea turtles
(sex ratios; Caretta caretta; Mediterranean; juvenile sea turtles)

Sažetak
Species with environmental sex determination may have sex ratios different from 1:1, and so sex ratio is an important variable in studies on the population dynamics of these species. This is particularly important for the endangered sea turtles, in order to understand the possible effects of human impacts and conservation measures. Unfortunately, only adults show an evident external sexual dimorphism, so that sex ratio data are difficult to obtain and are limited for the juvenile class, which represents the largest part of a population. Here we present the first extensive assessment of sex ratio of juvenile loggerhead turtles (Caretta caretta) in the Mediterranean Sea. A total of 310 dead turtles from four different areas were sexed by direct examination of gonads, the most reliable sexing method. Females were 54.2% of the whole sample, and no significant differences were found between the study areas. However, this value cannot be ascribed to a single population, because specimens from different nesting sites, both within and outside the Mediterranean, share the same foraging areas and each population may potentially contribute with a different sex ratio. Although we found an unbiased sex ratio, when other information from the region about distribution, mixed stocks, and sex ratios are considered, actually present results are compatible with a hypothetical scenario in which a majority of females are produced in the Mediterranean nesting beaches.

Izvorni jezik
Engleski

Znanstvena područja
Biologija

POVEZANOST RADA