The Conservation Biology Research Group at the University of Malta has been carrying out long-term field research on loggerhead sea turtles (Caretta caretta) in Maltese waters.  This study, led by Prof. Adriana Vella, was conducted in collaboration with the Environment and Resources Authority(ERA) and was published in the international peer-reviewed scientific journal ‘Animals’.

The publication can be accessed online.

This is the first scientific study that utilised genetic data for a more comprehensive understanding of reproductive behaviour of the loggerhead sea turtle from Maltese waters.  The ERA had provided dead hatchlings and undeveloped dead embryos that were collected from documented nesting sites between 2020 and 2022.

In-depth genetic data analyses, possible through an ERA permit, revealed that there were two instances where the adult nesting females returned twice to a beach to lay separate clutches of eggs within the same nesting season. Interestingly however, one of these females traversed a long distance before going to nest another clutch of eggs further away from the first beach.  This may be indicative of disturbance in the surroundings of the first nesting site.  The peak turtle nesting period coincides with the peak in number of visitors and anthropogenic activities in bays and beaches.

Results of this study also indicated the occurrence of multiple paternity resulting from polyandry, that is females mating with multiple males. This was however only confirmed for one of the various clutches investigated.

While multiple nesting per season and polyandry behaviours are commonly recorded in sea turtles, such data for the central Mediterranean is relatively limited. Therefore, this study provides a valuable detailed insight into the C. caretta mating and nesting behaviour in the region, achieved using genetic markers. Genetic tools are valuable in monitoring and understanding flagship and vulnerable species and are important assets in the field of conservation biology.

This research group from the Department of Biology, Faculty of Science, University of Malta, is active in studying various other aspects of the species C. caretta, while also training research students in the valuable and versatile skills required to decrease the gaps of knowledge on sea turtles and their urgent effective conservation needs.

Further information is also available by contacting Prof. Adriana Vella.

22 January 2024