Environmental impacts and causation of 'beached' Drifting Fish Aggregating Devices around Seychelles Islands: a preliminary report on data collected by Island Conservation Society

In the past decade the number of Drifting Fish Aggregating Devices (DFADs) deployed by tuna purse seine vessels has risen sharply. The increased number of deployments has seen an increased number of lost DFADs. These lost DFADs continue to drift with ocean currents and a large number eventually come into contact with land and ‘beach’, becoming stuck in a wide range of habitats. Here we detail the first attempt to assess the environmental impact and causation of lost DFADs that have become beached on and around Seychelles islands. The data presented shows that vessels owned by Spanish companies are responsible for 76% of the DFADs found beached in the study area. The data also shows that there has been a move by the fishing industry towards ‘non-entangling’ DFADs that make use of ‘sausage nets’ to reduce the entanglement of sharks and turtles in the open ocean but that these devices still pose an entanglement risk when they come into contact with coral reefs. We highlight the difficulties caused by a lack of available information on DFAD deployment numbers and locations and make recommendations including the removal of all nets from DFAD construction and increased use of bio-degradable materials.