期刊名称:International Journal of Comparative Psychology
印刷版ISSN:0889-3667
出版年度:2003
卷号:16
期号:2
页码:143-155
出版社:University of California Press
摘要:Studies focusing on the visual cues sea turtles use to orient between the nesting site and the sea indicate that sea turtles use diffuse images for orientation and are highly myopic on land. The visual environment encountered by sea turtles, however, is very different in water than on land. In this study, operant conditioning techniques were used to explore the visual acuity of juvenile loggerhead sea turtles ( Caretta caretta ) in the marine environment. Turtles were trained, in a tank setting, to distinguish between a 45 mm striped panel and 50% gray panel by using squid as a food reward. Though the pace of training was limited by our guidelines for holding these animals in captivity and the amount of food we could give each animal in a week, all turtles were trained in under a month. Once training was achieved, the stripes were reduced in size (stripe width ranging from 45.0 – 0.035 mm) until the turtle chose the striped panel over the 50% gray panel based on chance; this level of choice was designated as threshold. Mean acuity threshold level for all turtles tested was found to be 0.078 (visual angle of 12.89 minutes of arc). These results are similar to those of other marine species and indicate that loggerhead sea turtles use distinct visual cues in the aquatic environment.