DUGi

Estudio de la viabilidad de la fotoidentificación en recién nacidos de tortuga boba (Caretta caretta) y de la variación de las escamas a lo largo de los primeros seis meses de vida

http://dugi.udg.edu/item/http:@@@@hdl.handle.net@@10256@@16466

This work focuses on the identification by facial recognition in newborns of loggerhead turtle (Caretta caretta). The photo-identification (photo-ID) opens new possibilities to many studies on population dynamics, sex ratio or migration. Conservation work depends on our knowledge of the population, and for that individuals must be identified. In marine turtles the problem arises when it comes to identifying newborns that, due to their size, cannot be marked with rings, with PIT or other methods, as adults are marked. In adults, the technique of photo-ID utilizing the scale pattern of the facial profile, is also used. The objective of this study is to validate photo-ID as a tool for the identification of turtles which have been photographed at birth, for the rest of their lives. To this end, we studied the viability of the software of P.I.T.MAR. (turtle facial identification program) for the identification, by means of images, of loggerhead turtle individuals obtained during the first six months of life. The stability of the facial scale pattern throughout these firsts months will be studied. To analyze the changes in this pattern and to check if the software is sensitive to these changes. Understanding the patterns of potential variation of the scales in turtle newborns could allow corrections in the criteria of individual identification of the turtles improving its effectiveness. Our results show that there are changes in the scale pattern of the facial profile during the first year of life of the individuals, these changes are mainly due to growth and pigmentation. The software is sensitive to these changes because the identification capacity decreases with the increasing period between images of the same individual. The IF is a promising technique for individual identification. More studies are needed in this field, increasing the sample and developing the software to adapt it to the recognition of turtle individuals in early stages