implications of turning behaviour performed by Amazonian manatees after release into the wild

• Published in: Journal of ethology Vol. 30; no. 1; pp. 187 - 190
• Main Authors: Kikuchi, Mumi, da Silva, Vera M. F, Rosas, Fernando C. W, Souza, Diogo, Miyazaki, Nobuyuki
• Format: Journal Article
• Language: English
• Published: Japan Springer-Verlag 2012; Springer Japan; Springer
• Subjects: Animal Ecology; Animal ethology; animals; Behavioral Sciences; Biological and medical sciences; Biomedical and Life Sciences; color; Evolutionary Biology; forests; Fundamental and applied biological sciences. Psychology; hairs; Life Sciences; Mammalia; Psychology. Psychoanalysis. Psychiatry; setae (animal); Short Communication; Trichechus; Trichechus inunguis; Vertebrata; vision; Zoology; South America; America; Amazon Basin; 3D-movements; Diving behaviour; Spatial orientation; Environmental factor; Animal active movement; Circular; Vertebrata; Mammalia; Trichechus inunguis; Sirenia; Turbidity; Diving; Behavior; Vibrissa
• ISSN: 0289-0771; 1439-5444
• DOI: 10.1007/s10164-011-0290-0

Sirenians have dichromatic colour vision and tactile hairs but have not developed underwater echolocation. Amazonian manatees (Trichechus inunguis) live in turbid water and it has been unclear how they understand their surroundings. In this study, we recorded the 3D movements of two captive-raised Amazonian manatees. The results revealed that the manatees always swam in a circular pattern. Both animals used slower, narrower turning motions as they approached the flooded forests, which is abundant in aquatic vegetation. Therefore, we suggest that these two manatees swam in a circular pattern to detect all directions of their surroundings especially using sensitive facial bristles.