Abandoned, lost, or otherwise discarded fishing gear is a significant source of marine litter. About 640 thousand tons of fishing equipment are abandoned, lost, or dumped into the ocean each year. Such ‘ghost’ fishing gear is one of the most harmful forms of marine debris in the oceans today as it traps and kills marine wildlife randomly and unselectively. Moreover, there is chemical contamination with disruptive effects on marine species. As a result, human health is also impacted, with marine litter serving as a vehicle for diseases that contaminate the food chain.
The problem is more visible in Asian countries like Taiwan, which has a flourishing fishery industry and one of the world's largest fishing fleets. It is one of the countries contributing significantly to the problem with an average of 12.7 m3 of marine litter accumulating per kilometer along the coastline, 70% of which is caused by fishing gear. Yet precise data on the stocks and flows of commercial fishing gear in Taiwan is not available. To remedy this lack of insight, a study, consisting of a material flow analysis of commercial fishing gear in Taiwan, has been performed designed to improve Taiwan’s approach to fishery management and to prevent leakages of fishery waste.
A team of researchers led by Dr. Falk Schneider from National Cheng Kung University (NCKU), Taiwan has now conducted a material flow analysis of several types of fishing gear, with the goal of supporting Taiwanese policymakers on the development of appropriate marine litter prevention policies.
The project addressed the following three questions: How much fishing gear stock is actually in the system? How to stop fishing gear from turning into ocean waste? And, what policies are needed to effectively manage fishing gear?
The researchers first created a stakeholder map to establish the general flow structure of the commercial fishing gear used in Taiwan. The life cycle of the fishing gear was divided into five stages: use, repair, storage, spillage to the ocean, and end-of-life. Following that, stakeholders from both government agencies and private companies were approached to gather quantitative data on current fishing gear stocks and flows. Next, the material flow analysis software STAN 2.7 was used to analyze the data and visualize the material flow model to identify pollution hotspots and spillage points.
The total input was estimated to be 8,846 tons/year, with the total output being 4,271 tons/year. About 2,722 tons of fishing equipment were estimated to be lost or dumped in the ocean annually after being used. Some 1,172 tons of fishing gear required maintenance, 1,062 tons were stored in the harbour, and 3,529 tons entered the end-of-life stage. 1,538 tons of waste fishing gear were recycled; 2,630 tons were incinerated while another 103 tons, went to landfill.
The project painted a dispiriting picture of the way waste fishing gear is dealt with: literally tons of commercial fishing gear are dumped into the ocean every year, while over another ton of discarded gear is left untreated in harbours for storage.
The project yielded insights into a few critical steps that could be taken to transition to a more sustainable fishing industry. Schneider: "The Taiwanese government must collect data in a systematic manner to monitor and manage the fishing gear waste streams. Furthermore, a meeting should be convened between stakeholders from the fishery sector, government agencies, and non-governmental organisations to facilitate knowledge sharing toward more sustainable fisheries."
Overall, this research could serve as a foundation for the dissemination of best practices for preventing marine litter in Asia and around the world, he added.