Defensive responses of gopher tortoises (Gopherus polyphemus) are influenced by risk assessment and level of habituation to humans
MetadataShow full item record
Species that are either sessile or too slow to resort to flight may instead rely on defences suchas natural armour or protective structures, but they will still face the same economic decisionsas do more mobile species about when to re-emerge from cover. The gopher tortoise (Gopheruspolyphemus) is a species of conservation significance due to its important role as an ecosystem engineer and habitat loss due to human activities. In this study, we examined escape responses ofgopher tortoises approached by a human observer. Our data supported our prediction that the levelof disturbance would influence escape responses, with animals that were picked and handled taking longer to emerge and move off than animals that had simply been approached or approached and walked around. We also found that tortoises took half as long to extend their heads at our studysite, where tortoises exposed to a high level of benign human activity over a long period, compared with an adjacent site where there had been minimal human interaction with tortoises. These data suggest that gopher tortoises adjust their escape responses according to the level of risk they are exposed to. Over the long-term, this plasticity in escape responses can potentially result in some level of habituation to human presence.
Showing items related by title, author, creator and subject.
Switching to Plan B: changes in the escape tactics of two grasshopper species (Acrididae: Orthoptera) in response to repeated predatory approachesBateman, Bill; Fleming, P. (2014)Most studies examining escape behaviour have considered single approaches and single fleeing responses; few have considered how organisms’ response is influenced by persistent pursuit. We explored fleeing behaviour of two ...
Living on the edge: Effects of body size, group density and microhabitat selection on escape behaviour of southern leopard frogs Lithobates sphenocephalusBateman, Bill; Fleming, P. (2014)Models of optimal escape strategy predict that animals should move away when the costs of fleeing (metabolic and opportunity costs) are outweighed by the costs of remaining. These theoretical models predict that more ...
Bateman, Bill; Fleming, P. (2014)Optimal escape theory predicts that animals should moderate their flight responses according to the level of risk represented by a potential predator. This theory should apply even when organisms are habituated to ...