title: Individual-level behavioral responses of immature green turtles to snorkeler disturbance.
abstract: Despite many positive benefits of ecotourism, increased human encounters with wildlife may have detrimental effects on wild animals. As charismatic megafauna, nesting and foraging sea turtles are increasingly the focus of ecotourism activities. The purpose of our study was to quantify the behavioral responses of immature green turtles (Chelonia mydas) to disturbance by snorkelers, and to investigate whether turtles have individual-level responses to snorkeler disturbance. Using a standardized disturbance stimulus in the field, we recorded turtle behaviors pre- and post-disturbance by snorkelers. Ninety percent of turtles disturbed by snorkeler (n = 192) initiated their flights at distances of ≤3 m. Using principal component analysis, we identified two distinct turtle personality types, 'bold' and 'timid', based upon 145 encounters of 19 individually identified turtles and five disturbance response variables. There was significant intra-individual repeatability in behavioral responses to disturbance, but bolder turtles had more behavioral plasticity and less consistent responses than more timid individuals. Bolder individuals with reduced evasion responses might be at a higher risk of shark predation, while more timid turtles might have greater energetic consequences due to non-lethal predator effects and repeated snorkeler disturbance. Over the longer term, a turtle population with a mix of bold and timid individuals may promote more resilient populations. We recommend that snorkelers maintain >3 m distance from immature green turtles when snorkeling, and that ecotourism activities be temporally and spatially stratified. Further, turtle watching guidelines need to be communicated to both tour operators and independent snorkelers to reduce the disturbance of turtles.
authors.affiliation: Department of Environmental Conservation and Intercampus Marine Science Graduate Program, University of Massachusetts Amherst, 160 Holdsworth Way, Amherst, MA, 01003, USA. lpgriffin@eco.umass.edu.
authors.forename: Lucas P
authors.initials: LP
authors.lastname: Griffin
authors.affiliation: Fish Ecology and Conservation Physiology Laboratory, Ottawa-Carleton Institute for Biology, Carleton University, 1125 Colonel By Dr., Ottawa, ON, K1S 5B6, Canada.
authors.forename: Jacob W
authors.initials: JW
authors.lastname: Brownscombe
authors.affiliation: Department of Environmental Conservation, University of Massachusetts Amherst, 160 Holdsworth Way, Amherst, MA, 01003, USA.
authors.forename: Tyler O
authors.initials: TO
authors.lastname: Gagné
authors.affiliation: Fish Ecology and Conservation Physiology Laboratory, Ottawa-Carleton Institute for Biology, Carleton University, 1125 Colonel By Dr., Ottawa, ON, K1S 5B6, Canada.|School of Life and Environmental Sciences, University of Sydney, Heydon-Laurence Building A08, Sydney, NSW, 2006, Australia.
authors.forename: Alexander D M
authors.initials: AD
authors.lastname: Wilson
authors.affiliation: Fish Ecology and Conservation Physiology Laboratory, Ottawa-Carleton Institute for Biology, Carleton University, 1125 Colonel By Dr., Ottawa, ON, K1S 5B6, Canada.
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Cooke
authors.affiliation: Department of Environmental Conservation and Intercampus Marine Science Graduate Program, University of Massachusetts Amherst, 160 Holdsworth Way, Amherst, MA, 01003, USA.
authors.forename: Andy J
authors.initials: AJ
authors.lastname: Danylchuk
mesh_terms: D000818:Animals; D004242:Diving; D006801:Humans; D011235:Predatory Behavior; D012754:Sharks; D014426:Turtles
keywords: Ecotourism; Flight initiation distance; Personality; Principal component analysis; Repeatability