If female-bias occurs across an entire nesting beach it is termed ‘feminisation’ and results in reduced production of male hatchlings. For many tropical regions around the world, increases in the frequency of heavy rainfall events are predicted with increasing air temperature, which may counter the feminisation of turtle populations that would otherwise occur. Therefore, as part of the WWF-Australia ‘Turtle Cooling Project’, Melissa aimed to;
1. determine the importance of heavy rainfall events at key hawksbill and green turtle nesting beaches for male hatchling production in the Asia-Pacific region;
2. model past and future hatchling sex-ratios using sand and air temperature data proxies; and
3. use aerial surveys to estimate the breeding sex-ratio at a regionally significant green sea turtle mating ground in the southern GBR, Australia.

As many sea turtle rookeries globally are known to have a female-biased primary sex-ratio, we need to know how the adult population is responding and if males need to overcompensate for themselves. The project will provide new insights to better inform conservation managers on sex-ratio trends of key populations and their relative risk to feminisation.