| dc.description.abstract | Climate change threatens marine turtles that depend on beaches for nesting with temperature changes affecting embryonic development and sex determination. Sea level rise may destroy their nesting habitats, and warming temperatures may cause complete development failure and imbalanced sex ratios. It is critical, therefore, to understand the likely climate change impacts to ensure mitigation is undertaken. It is particularly useful to examine climate change impacts in areas already facing extreme environmental conditions. The northwestern Indian Ocean (NWIO) is a relatively understudied region regarding marine turtles. Key knowledge gaps helped shape the main aims of this thesis, and these are:
1. to understand the status of marine turtles in the NWIO region from published material and regional expert elicitation;
2. to analyze 20 years of available data on marine turtles in Abu Dhabi, United Arab Emirates;
3. to investigate nest temperatures in Abu Dhabi to estimate primary sex ratios and the likely impact of global climate change on population dynamics and conservation, and;
4. to estimate the level of nest inundation that might result from forecast sea level rises associated with climate change.
My key findings were that:
1. Significant research and conservation efforts have focused on marine turtles across the NWIO region. I identified major threats, knowledge gaps, impediments to practical conservation, and strengths and opportunities towards creating a knowledge base for future research.
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2. The long-term marine turtle conservation plan in Abu Dhabi Emirate covers nesting ecology, foraging, mortality investigations, and rehabilitation initiatives. The mean estimate of hawksbill turtle clutches per year was 220 while the foraging population of all species and all sizes found in the emirate is 5,550–7,488 individuals. The majority of mortality was due to drowning in abandoned nets. Further research, including additional in-water foraging studies, population structure, and comprehensive nesting trends, is vital.
3. Primary sex ratios of hawksbill hatchlings are prone to be highly female-biased (> 80 % female), and only nests in the first three weeks of the breeding season were likely to have produced male hatchlings.
4. Beaches at major nesting islands will be profoundly affected by inundation due to sea level rise, however, the core nesting areas will remain as potential nesting sites.
I propose additional management approaches under each aspect and a detailed list of research priorities for Abu Dhabi | en_GB |
