MOBULA 8 at the service of science

 As part of the Marine Litter initiative financed by the AFD (French Development Agency), which started in 2019, 32 drifting buoys are to be deployed in Indonesian waters before mid-2023 to study and understand the phenomena of marine debris accumulation.  

This is the context of the first scientific mission of The SeaCleaners and the Mobula 8. To complete its studies on the understanding of the accumulation of marine debris carried out in collaboration with the IRD (Institut de Recherche et Développement), our partner CLS (Collecte Localisation Satellite) has offered another of our partners, Universitas Udayana (UNUD), 10 drifting buoys. 

This project aims to gather a new set of in situ observations, and to further underline, if any were needed, the urgency of tackling marine plastic waste in Indonesia. 

 “These studies on the understanding of plastic drift in Indonesia have two main components,” explains Marc Lucas, oceanographer at CLS and head of the programme related to the clean-up of plastic at sea: “an in situ part to try to understand the circulation in the area of interest by deploying buoys equipped with a GPS and an Argos modem that allows the position to be recovered, and a modelling part: it is the wind and currents that move the plastics washed into the sea; as we cannot track all the plastics individually, we are using digital models* of the particles to try to represent their movement. The particles, just like our buoys, are affected by wind and current, so we can see where they go, how long they stay in certain places, what causes them to remobilise and go elsewhere. With the information provided by the models and the buoys, we can get a holistic view of what is happening to the plastic.” 

Depending on the season, the waste will go to different places: “With the monsoon cycle in Indonesia, there are reversals of currents and winds”, Marc continues: “We have thus highlighted that different areas were impacted by the waste, depending on the season. At a certain time of year, it tends to go towards the Timor Sea, to the east, and at another time towards the Indian Ocean: we have a beacon released from a river in Java that went all the way to Madagascar! In 6 months it has travelled almost 7,500 km, a clear and visible illustration that plastic pollution is not a local problem but a global one.”  

UNUD and The SeaCleaners will jointly deploy 10 buoys in the mouths and rivers of Bali. One in the Ijo Gading River on the west coast and the other in the Ayung River on the southeast coast. The researchers from Udayana University are therefore planning to assess, among other things, the speed at which waste is likely to reach the sea and where it is likely to go next. 

These buoys will support UNUD and The SeaCleaners in their efforts to combat marine plastic pollution by providing valuable information. Indeed, knowing where and why marine debris accumulates in certain areas is fundamental to increasing and optimising the effectiveness of ships and waste collection campaigns.   

In addition, 15 days a month, UNUD students will board the MOBULA 8 to carry out a detailed characterisation of the macroplastics collected in specific areas. 

 Gwenaële Coat, Scientific Director of The SeaCleaners, is delighted with this cooperation: “Fighting plastic pollution effectively involves curative action, preventive action and also an in-depth scientific understanding of the phenomena that contribute to plastic pollution in aquatic environments. MOBULA 8 combines these three dimensions and we are very pleased that its deployment is part of such important research programmes as those of CLS and the local university of Udayana. Collaborations such as these, with local actors, contribute to a better understanding of the systems and are essential”. 

* Representation of an object or phenomenon in a digital format.