title: Turtle mating patterns buffer against disruptive effects of climate change.
abstract: For organisms with temperature-dependent sex determination (TSD), skewed offspring sex ratios are common. However, climate warming poses the unique threat of producing extreme sex ratio biases that could ultimately lead to population extinctions. In marine turtles, highly female-skewed hatchling sex ratios already occur and predicted increases in global temperatures are expected to exacerbate this trend, unless species can adapt. However, it is not known whether offspring sex ratios persist into adulthood, or whether variation in male mating success intensifies the impact of a shortage of males on effective population size. Here, we use parentage analysis to show that in a rookery of the endangered green turtle (Chelonia mydas), despite an offspring sex ratio of 95 per cent females, there were at least 1.4 reproductive males to every breeding female. Our results suggest that male reproductive intervals may be shorter than the 2-4 years typical for females, and/or that males move between aggregations of receptive females, an inference supported by our satellite tracking, which shows that male turtles may visit multiple rookeries. We suggest that male mating patterns have the potential to buffer the disruptive effects of climate change on marine turtle populations, many of which are already seriously threatened.
authors.affiliation: Centre for Ecology and Conservation, University of Exeter, Cornwall Campus, Penryn TR10 9EZ, UK.
authors.forename: Lucy I
authors.initials: LI
authors.lastname: Wright
authors.forename: Kimberley L
authors.initials: KL
authors.lastname: Stokes
authors.forename: Wayne J
authors.initials: WJ
authors.lastname: Fuller
authors.forename: Brendan J
authors.initials: BJ
authors.lastname: Godley
authors.forename: Andrew
authors.initials: A
authors.lastname: McGowan
authors.forename: Robin
authors.initials: R
authors.lastname: Snape
authors.forename: Tom
authors.initials: T
authors.lastname: Tregenza
authors.forename: Annette C
authors.initials: AC
authors.lastname: Broderick
mesh_terms: D000818:Animals; D057231:Climate Change; D003535:Cyprus; D056727:Endangered Species; D005260:Female; D008297:Male; D018895:Microsatellite Repeats; D019849:Sex Determination Processes; D012744:Sex Ratio; D012726:Sexual Behavior, Animal / Q000502:physiology*; D018531:Spacecraft; D014426:Turtles / Q000502:physiology*