Overview
Climate change is altering the world’s ecosystems at an unprecedented rate and understanding the resilience of species and populations to withstand this change is critical to inform and prioritise conservation efforts.
About this opportunity
Like many reptiles, sea turtles exhibit temperature-dependent sex determination (TSD): incubation duration, hatch success, hatchling sex and fitness are all influenced by ambient temperatures. Through reduced hatch success and female-skewed sex ratios, climate change is thus likely to elicit significant population effects. Knowledge gaps remain however in the adaptive significance of TSD, how thermal microclimates drive variation in primary sex ratios, how these translate into adult sex ratios, and the potential for range shifts as new areas of suitable nesting habitat become available. This study will address these gaps, through a combination of field, lab and modelling approaches, focussing on the loggerhead sea turtle, Caretta caretta population of Cabo Verde, West Africa.
Objectives
- Use data on male and female breeding intervals to estimate optimal adult sex ratios for population viability
- Assess spatiotemporal variation in the thermal nesting environment and hatchling sex ratios to determine the population’s adaptive potential to mitigate future temperature increases and female bias
- Investigate patterns of multiple paternity in the rookery to assess breeding sex ratios and potential male scarcity
- Develop an individual-based model of hatchling dispersal from the Cabo Verde population to determine possibility of range expansion
Novelty
Reptiles are uniquely vulnerable to climate change and the adaptive significance of TSD remains poorly understood. The project will address existing gaps in our knowledge to broaden the conceptual understanding of TSD under climate change, whilst contributing directly to conservation management of sea turtles more broadly. This multidisciplinary project combines field, laboratory and modelling techniques and will allow the student to develop a well-rounded skillset for future employment. The loggerhead turtle population in Cabo Verde has in recent years shown dramatic increases in nesting densities and is one of the largest in the world, offering an ideal study system for prospective students to explore these concepts. The project will build upon unique multiyear datasets provided by project partners.
Timeliness
Climate change is a rapidly increasing driver for biodiversity loss in addition to habitat alteration/degradation and exploitation. Global temperature increases will influence all life history stages of sea turtles, a group of ecological, cultural, and socioeconomic importance. The outputs of this project will address key research priorities and be incorporated into conservation management.
Role Criteria
Essential
- Quantitative data analysis skills
- Interest in conservation biology
- Good communicator
- Can work productively as part of a team
Desirable
- Mathematical modelling experience/ability to learn modelling skills
- Molecular laboratory skills
- Experience in Python programming language
- Field conservation experience
Whilst this project has the opportunity for overseas fieldwork, we will welcome and consider applications from candidates of all backgrounds, abilities and circumstances. Support will be provided throughout the project.