Meeting Abstract
Animals live in complex environments, and the effects of environment on behavior are important for understanding their ecology. An essential step in gaining this understanding is examining how animals sense and respond to environmental cues. Branches in natural arboreal habitats pose discrete choices and differ in their size, which is often correlated with mechanical properties such as stiffness. Although brown tree snakes (Boiga irregularis) are known to use visual cues to choose between perches, the effects of branch stiffness on perch choice are unknown. Hence, we used cylinders with V-shaped arrays of pegs to test whether the brown tree snakes preferred artificial branches with variable diameters and compliance. We also used a repeated measures procedure to test if perch preference was altered by experience over the course of six days. When all perches were rigid and the overall width of the V-shape was constant, the snakes had no preference based on the diameters of the cylinders and pegs. By contrast, after two days snakes developed and maintained a preference for larger rigid perches rather than the compliant perches with smaller diameters. However, this preference for larger diameter perches did not persist after both perches were made rigid again. This suggests that the snakes were not able to associate rigidity (a tactile sensation) with perch diameter (a visual cue). A touching behavior, in which the snakes repeatedly tapped the compliant perch, emerged when the snakes were exposed to the compliant perch, but this was exclusive to interactions with the compliant perch. Hence, our results show that the snakes sampled their environment more when interacting with compliant perches. Overall our study shows that perch compliance alters the behavior of Boiga irregularis.
