Investigating the dispersal of hawksbill sea turtle hatchlings in the Arabian Gulf

Details

Supervisors

Hanert, Emmanuel ; Deleersnijder, Eric

Faculty

Ecole polytechnique de Louvain

Degree label

Master [120] : ingénieur civil en mathématiques appliquées, à finalité spécialisée

Abstract

The lost years of sea turtles is a subject biologists are still very much investigating every day. Between the moment they hatch, battle to reach offshore water and then come back years later to lay their own eggs, very little is known about the journey of sea turtles. How to model the way they swim in order to get to safe places is one of the challenges that was faced. In this work, we will focus on Hawksbill sea turtles in the Arabian Gulf. How many leave the Gulf? Are they affected by the multiple artificial structures of Qatar? Thanks to the oceanic models SLIM and NEMO we will be able to simulate real life dispersal of the hatchlings. We will show that a small portion of hatchlings do in fact leave the Gulf and that they do not often interact with artificial structures such as Ras Laffan's LNG terminal or the Halul oil terminal. Artificial structures do not seem to disturb the hatchlings dispersal in a significant way. For the regional-scale analysis, we will observe that hatchlings seem to leave at speficic periods during the year and that there are certain areas in which they are more present than others in the Gulf. The results here seem to show that during their dispersal around the Gulf, turtles might, at certain periods, gather around certain areas such as the South Pars/North Dome gas condensate field. It also shows that, even though it is only a small fraction, some turtles might get trapped inside artificial structures and not be able to get out due to the currents. Perspective for future research on the topic is first to model the swimming of turtles in a more realistic way. Another improvement that could be made is to take a model that has better resolution near the coasts for the regional-scale analysis as the NEMO model is limited in that regard. Hopefully this is a step towards making sure of the well-being of sea turtles in the Gulf.