Discarded fishing gear, oil drums, car parts, nylon ropes and metal cables were among the extensive litter discovered by an underwater robot exploring 420,000 square metres of Malta's sea floor.

The robot, which descended to depths of up to 1,040 metres, came across litter on every one of its 200-plus dives across two separate expeditions held in 2015 and 2016, University scientists said. 

Scientists from the University of Malta's Department of Biology, who are responsible for analysing the robot's results, were surprised at the amount of litter they noted on the sea floor.

Discarded fishing gear as well as plastic, glass bottles and metallic objects including rods, cables, discarded car parts and oil drums, have accumulated in the deep sea. In particular, discarded fishing gear such as trawl nets, nylon longlines and limestone slabs with synthetic ropes from the dolphinfish [lampuki] fishery were common at offshore sites.

Photo: Oceana

Dolphinfish aggregation devices [kannizzati] are anchored to the sea floor with limestone slabs, and the mooring ropes are cut off and discarded at the end of each fishing season. The limestone slabs may cause direct damage to reef species when they are deposited on the bottom, while the long discarded ropes can become entangled with organisms such as vulnerable deep-water stony and gorgonian corals. Nylon lines from bottom longline fisheries targeting for example hake, greater forkbeard, and dogfish were frequently found entangled on deep-sea reefs.

The expeditions form part of the LIFE BaĦAR for N2K project, which seeks to ensure that vulnerable marine habitats, including deep water coral reefs, are protected by virtue of being designated as Natura 2000 sites, the European Union network that collectively safeguards the EU’s most valuable natural areas.

Scientists hope that the survey information gathered will make it easier to formulate effective conservation measures to address marine litter, ghost fishing and other threats to marine habitats.

An After-LIFE Conservation Plan detailing management and conservation activities after the project end date will be formulated through the LIFE BaĦAR for N2K project to guide all the stakeholders involved. 

The LIFE BaĦAR for N2K project is co-financed by the EU LIFE+ Funding Programme, and is led by the Environment and Resources Authority (ERA), with the Ministry for Sustainable Development, the Environment and Climate Change (MSDEC), the Department of Fisheries and Aquaculture (DFA), the Department of Biology of the University of Malta (DoB-UoM) and Oceana as partners. 

Photo: Oceana