Sea-based sources of marine litter

Lead agencies: Food and Agriculture Organization (FAO) and International Maritime Organization (IMO)

Co-sponsor: United Nations Environment Programme (UNEP)


In the last decade there has been growing knowledge on the levels, sources, negative effects of marine litter and microplastics in the world’s ocean, as well as measures to reduce their impacts. However, levels of marine litter, in particular plastic litter, are continuing to increase, together with their harmful impacts, including those on biodiversity, ecosystems, fisheries, animal welfare, maritime transport and safety at sea. Recently there has been increasing political will and momentum to address marine litter, in particular related to SDG14.1 on marine pollution, within the 2030 Agenda for Sustainable Development, which has played a key role in driving increased action on this issue at national, regional and international levels.

However, within this context of increased knowledge and political motivation, land-based sources of marine litter continue to dominate scientific outputs, public attention and political dialogue. Consideration of sea-based sources of marine litter, which includes litter originating from the fishing and shipping industries, in particular abandoned, lost or otherwise discarded fishing gear (ALDFG), are still several steps behind other sources in our understanding of levels and their impacts. It is sometimes claimed that 80% of marine litter comes from land-based sources, however this statistic is now widely disputed and ought to be validated. It is acknowledged that in some contexts the impacts from sea-based sources, in particular ALDFG, may be more harmful than other types and sources of marine debris, particularly with regard to ‘ghost fishing’, the entanglement of marine species and as a navigational hazard to safety at sea.

Consequently, UN agencies, in particular the Food and Agriculture Organization (FAO) and the International Maritime Organization (IMO), have been stepping up their efforts to meet this challenge. Both organizations have adopted policy instruments which deal with sea-based sources of marine litter and both organizations have been mandated by their members to increase their efforts on this issue and to establish strategies and action plans.

Scope of work

Following an agreement in principle at the 45th annual session of GESAMP in 2018, the Working Group on sea-based sources of marine litter (WG 43) was established formally in April 2019. The overall objective of WG 43 is to build a broader understanding of sea-based sources of marine litter, in particular from the shipping and fishing sectors, including the relative contribution of different sources, analysis of plastic use and management within both industries and the range and extent of impacts from sea-based sources of marine litter. The Working Group will also work to build a more comprehensive understanding of specific types of sea-based sources of marine litter, and to guide interventions on these sources based on identified priorities, drawing upon the expertise of FAO, IMO, UN Environment and other relevant organizations and experts.

The Working Group has two concurrent work-streams:

Work-stream 1, with an overarching scoping study which would, amongst other objectives, support the initial information requirements of IMO’s Action plan to address marine litter from ships and help identify priorities within this overarching scope.

Work-stream 2, with recognition that some types of sea-based sources of marine litter, such as ALDFG, are further progressed in terms of available information but require more focussed scientific attention to inform interventions. The work-stream will focus on specific areas of research to fulfil this requirement. ALDFG will be the focus based on the existing knowledge that this is a major source of marine litter from ships and the fishing sector specifically. It is also already identifiable as a key area of work for both FAO and IMO whose Members have highlighted an urgent need to address this issue.

Tentative work plan

WG 43 is aiming to produce its first report by early 2020, and a second report by the end of 2020.

Terms of Reference

Work-stream 1 – Global overview

A global overview of sea-based sources of marine litter, including fishing gear and other shipping related litter, which should include:

ToR 1: An identification of sources of marine litter from sea-based sources, including but not limited to:

a. fishing operations (e.g. gear, packaging material, strapping bands);

b. aquaculture (e.g. cages, buoys, netting, packaging materials structures);

c. shipping (garbage, hull scrapings, containers, spoilt cargo, grey water, ropes and cargo nets);

d. dumping of waste and other matter at sea, derelict fibreglass (FRP) vessels;

e. other (e.g. recreational boating, recreational fishing)

ToR 2: An estimate of the relative contribution and impacts of different sea-based sources of marine litter.

ToR 3: An analysis of how much plastic is produced and used by the fishing and shipping industries. This would include what kind of plastic is manufactured and used by these industries, as well as an overview of the existing waste management streams for these plastics and how these vary by region.

ToR 4: An assessment of data gaps, as identified under ToR 1 to 3 above, and prioritization for further work.

Work-stream 2 - ALDFG

Phase 1: Distribution, trends and impacts

ToR 5: Identification of ALDFG hotspots – utilizing data collected in various platforms including the GGGI data portal and building upon work done in CSIRO gear loss study (pending publication).

ToR 6: Quantification of the impacts of ALDFG – environmental, social and economic.

Phase 2. Interventions

ToR 7: Review and comparison of options for solution delivery by way of analysis of results of all available data from existing sources, including quantification of benefits, mapping of solution ‘hubs’ against ALDFG hotspots and identifying common themes and gaps that have emerged through recommendations.

The Group held its second meeting at the Food and Agriculture Organization (FAO) in Rome from Monday 28 to Wednesday 30 October 2019. The focus of this meeting was to indentify knowledge and data gaps and agree on planned outputs such as the finalization of the first interim report.