Marine debris refers to any persistent, processed or manufactured material that is solid in nature, which has been disposed, abandoned or discarded in the coastal and marine environment. Plastic/beverage bottles, food wrappers, straws, cigarette butts, bottle caps, grocery/plastic bags, fishing nets, buckets and packaging materials are some of the more common types of marine debris. Seven of these items are made of plastic. More than half of that marine debris comprises of plastic, which is a potentially hazardous and persistent pollutant that breaks up into micro plastics which a wide range of marine organisms can take up/consider as a food source.
Plastics are most sought after because of their durability as they can there are many ways in which they can be used. Plastics have some advantages, for example, they help to improve thermal insulation, they help lower fuel consumption in automotives and aircrafts, they help in food preservation and lastly, they help to improve medical product efficacy. However, the problem arises when there is poor management of plastics. Plastics end up in the ocean due to a number of reasons:
- Illegal practices
- Littering by individuals and groups
- A lack of awareness on the consumer’s part
- Accidental input from land-bases activities
- Poor waste management by the private and public sector.
Marine litter can come from land-based sources, either from the coastal or inland areas. Some of these areas include riverbanks; piers; beaches; ponds, rivers and lakes that have been used as illegal dumping sites; docks; waste dumps located on coastlines; tourists and beach goers.
Effects of plastics on plants and animals
Marine plastics affect marine species either through entanglement or when they are ingested. Sea turtles, seagulls and tooth whales are some of the marine species that have been commonly found with considerable amounts of plastics inside their guts when necropsies have been performed on beached specimens. The thought is that plastic items are most of the times, mistaken as prey and when ingested by marine animals, they block the gut and this causing internal injuries and starvation. The tendency of discarded or lost fishing nets to continue trapping marine organisms is referred to as ghost fishing and this practice leads to unnecessary depletion of species populations in the marine environment.
Plastics that are in marine food webs, can act as transport mediums and as highly potential sources of chemicals with high levels of toxicity. Such chemicals can cause sub lethal effects in marine life. Entanglement can also occur which causes restricted mobility, amputation of limbs, wounding, drowning, smothering and starvation, all of which would likely result in the death of marine animals.
A report from Plymouth University showed that when lugworms (marine organism) ingested micro plastics, their health significantly reduced because of harmful chemicals like hydrocarbons, lame retardants and antimicrobials that are found in some plastics. Other marine life that are affected include:
- Fish found in the Pacific North area alone, have been found to have ingested 12,000 – 20, 000 tons of plastic. A recent study conducted showed that fish found at the markets in California had plastic microfibers in their guts.
- Sea turtles - the stomachs of loggerhead sea turtles have been found to contain soft plastic, styrofoam and ropes.
- Sea birds - most laysan albatross chicks have pieces of plastics in their stomachs that have been fed to them by their parents after the pieces were mistaken for food. It has been estimated that close to 60 percent of seabird species have consumed plastic pieces and that the number is highly likely to increase in the coming years.
- Marine mammals – plastic debris of substantial quantity has been found in the habitat of the Hawaiian monk seals which is an endangered species, including areas that act as nurseries for their pups. Death by entanglement severely undermines recovery measures and efforts to reduce the rate of extinction of this species. Injury and death through entanglement has also affected the sea lion which is an endangered species and packing bands are to be blamed as being the, with packing bands comprising the most common entangling material. In 2008, plastic debris, fishing net scraps and rope was found inside two sperm whales along the California coast.
- Coral reefs- several species of coral reefs can be killed by plastic debris through entanglement; entanglement can also cause the breakage and damage of coral reefs. Marine debris has been found in the North-western Hawaiian island reefs.
International Legal framework
Basel Convention on the Control of Transboundary Movements of Hazardous Wastes and their Disposal
On March 1989, this convention was adopted and later on, entered into force in May 1992. It is concerned with the movement of and disposing off, of hazardous wastes and other wastes. The movement and disposal of such should be that it better helps to protect the environment and human health. All practicable steps should also be taken by states to ensure that all wastes which are hazardous and others, are managed in a way which protection is extended to the environment and people's health, especially those living in that environment. Hazardous wastes and other wastes, the movement of which normally occurs through rail, road, inland waterway, air or the sea. The parties have a duty to ensure that all persons are prohibited from engaging in the transportation or disposal of any wastes considered as hazardous unless they have authorization to do so by the national jurisdictions that they fall under; the movement of such wastes, which is transboundary in nature,should be packaged, labelled and transported according to the relevant practices, standards and rules that have been recognized internationally while accompanied by a movement document from the point of commencement to that of disposal. The Convention does list various disposal operations that mainly occur in practice and the release of hazardous wastes and other wastes into seas/oceans is one of such ways that wastes is usually disposed of. Plastics can only be categorized and defined as wastes under this convention, if they show any show characteristics of being hazardous as it is outlined and listed under Annex III.
United Nations Convention on the Law of the Sea (UNCLOS)
Pollution of the marine environment, as per the convention, is defined as the introduction of substances and energy that will in all likelihood lead to harmful effects on the flora and fauna living in the marine environment, hindrances to marine activities like fishing and other uses (legitimate) of the sea. The convention outlines a number of duties and obligations that States have towards the marine environment but the general obligation being the protection and preservation of the marine environment. The cooperation of States is urged both globally and regionally, whether by the direct use of or through such international bodies competent in such areas, in the elaboration and the formulation of international standards, practices, procedures and rules that further aid in the protection and preservation of such an environment. Necessary measures should be undertaken by States to ensure the effective control, prevention and reduction of waste disposal into the marine environment which interferes with the marine environment’s ecological balance. By protecting and the conserving the natural resources, damage to the flora and fauna that is found in the marine environment is prevented. Measures taken by States should be those that will help minimize substances that are harmful, noxious and toxic from land-based sources, sea vessels or from dumping, being released into the marine environment.
Convention on the Prevention of Marine Pollution by Dumping of Wastes and other Matter (London Convention)
This Convention reinforces a well known fact that the environment around marine areas and other living organisms existing in such areas, are crucial to humanity and that everyone has a vested interest in ensuring that the marine environment is well managed. It is majorly concerned with pollution to the sea. Dumping, under this convention, is defined as the disposing of wastes or other matter in a deliberate nature, at sea. The parties to this convention are urged, both individually and collectively, to take the necessary steps required to prevent the sea from getting polluted especially through waste dumping. The Convention acknowledges that pollution by dumping of wastes will most certainly harm flora and fauna found in marine areas/environment. Wastes listed under Annex I are prohibited from being dumped: plastics and other synthetic materials like nets and ropes fall under the category of wastes that should not be dumped into sea and those listed in Annex II will require special permit prior to dumping.
International Convention for the Prevention of Pollution from Ships (MARPOL 73/78)
This Convention is a combination of the1973 convention and the protocol of 1978. It tackles the issue of harmful substances getting discharged from ships into the marine environment. Annex V was part of the Amendments that were done to the convention and it came into force on 1 January 2013. Under this Annex, the disposal of all plastics, fishing nets that are made of synthetic material, plastic garbage bags, incinerator ash from plastic products containing toxic heavy metals and synthetic ropes is totally prohibited unless under very specific circumstances. The amendments list requirements for ships to have garbage management plans and reception facilities in ports for receiving wastes.
FAO Code of Conduct for Responsible Fishing
This code seeks to provide principles and international standards of behaviour needed to ensure that the conservation, management and development of aquatic living resources occurs effectively, bearing in mind the respect for biodiversity and the ecosystem. States and fisheries management organizations, whether those found at the regional or subregional level, should adopt measures that better help protect endangered species and also conserve the biodiversity of aquatic habitats and ecosystems. Adverse environmental impacts from human activities should also be accessed and corrected. The impacts on associated or dependent species through pollution, wastes or ghost fishing should also be minimized by using environmentally safe fishing gear and developing techniques that are safe for the environment.
Convention Biological Diversity
The convention notes that certain human activities are the cause of the significant reduction of biological diversity and the importance of anticipating and preventing the causes that lead to such significant loss or reduction of the biological diversity. Parties to this convention are urged to identify practices which have or are likely to have negative effects on the conserving of and the use of biological diversity.
Convention on the Conservation of Migratory Species of Wild Animals (CMS/ Bonn Convention)
This convention states that States should and must protect wild animal species that are migratory in nature, which pass through or live inside their boundaries. Parties are urged to minimize the harmful effects of activities that impede migration of such species especially those considered to be endangered and are listed in Annex I.
Conference of the Parties to the convention on the Conservation of Migratory Species of Wild Animals held in Bergen, Norway (November 2011)
Marine debris was seen as a major concern during this conference of the parties as
- It negatively impacted migratory wildlife species for example, turtles, sharks, birds and other marine mammals that are on the verge of extinction.
- It could cause mortality in various migratory species through entanglement or ingestion.
The conference encouraged parties to try and identify locations along the coast and ocean areas where marine debris accumulates in order to identify areas of concern. Parties to the Convention were also encouraged to work with regional neighbouring states to identify and address sources and impacts of marine debris as marine debris cannot be limited to state borders.
Agenda 21 provides that the marine environment, which includes seas oceans and adjacent coastal areas, is an integral part of the life support system that is global and an asset to sustainable development. The highest contributor to marine pollution is land-based sources at nearly 70 percent. Litter and plastics are included in a list of contaminants that are a key threat to the marine environment. States are encouraged to ensure the application of anticipatory, precautionary and preventative measures to help avoid the degradation and also the reduction of risks pertaining to the long-tem and irreversible effects on the marine environment. The Agenda 21 advocates the employment of the precautionary and anticipatory approaches as they will be more useful in preventing continual degradation of the marine environment instead of the usual reactive approach that is normally employed. For this to succeed the following need to be implemented and adopted: measures that are precautionary; production techniques that are clean; recycling methods; environmental impact assessments and management criteria that are of high quality for the proper handling of substances that are hazardous.
United Nations Fish Stocks Agreement
This agreement was adopted on 4 August 1995 by the United Nations Conference on Straddling Fish stocks and Highly Migratory Fish Stocks. It implements the provisions of the law of the sea convention, that relate to the conserving and managing of straddling fish stocks and high migratory fish stocks. Coastal States and States that engage in fishing in the high seas are required to assess human activities and factors which are environmental in nature that target stocks and species of the same ecosystem. Such States are also urged to minimize pollution, ghost fishing through fishing gear that has been abandoned or lost and also to ensure that biodiversity in the marine environment is protected. The precautionary approach should also be utilised to better help in the management, exploitation and conservation of straddling fish stocks and highly migratory fish stocks so as to ensure the protection of marine living resources and the preservation of the marine environment.
Global Programme of Action for the Protection of the Marine Environment from Land-based Activities
The Global Programme of Action (GPA) was adopted in 1995 through the Washington Declaration. It is a comprehensive programme that aims to mitigate and prevent the marine and coastal environment from continual degradation which is caused by activities that are land-based. The GPA aims to facilitate the realization that states have a duty to preserve and protect the marine environment. The GPA lists five goals which include: a) the identification of the sources and impacts of land-based sources of marine pollution; b) the identification of priority problems for action; c) the setting of the objective management for these problem areas; d) the development of strategies to help in the achievement of these objectives and e) the evaluation of impacts of these strategies. The GPA list nine pollutant sources from land-based activities and litter is included in this list. The GPA advocates developing and implementing NPAs (National Programmes of Action) that will further help States to fulfil their duty to protect and preserve the marine environment from the pollution sources listed under the GPA.
Plan of Implementation of the World Summit on Sustainable Development, Johannesburg (2002)
The Johannesburg Plan acknowledges that seas, coastal areas, oceans and islands are part of an important aspect of the ecosystem of the earth and that the effective coordination and cooperation both regionally and globally, will go a long way to ensure that the oceans are sustainably developed; therefore states are invited and urged to implement, ratify or accede the United Nations Convention on the Law of the Sea of 1982 because it provides the blueprint for practices or activities that take place in the ocean and also to promote the implementation of Chapter 17 of Agenda 21 which gears towards the achievement of development that is sustainable, in oceans, seas and coastal areas.
Convention for the Protection and Development of the Marine Environment of the Wider Caribbean Region (The Cartagena Convention)
Parties to this convention are urged take appropriate measures that conform to international laws and this convention, to control, prevent or reduce pollution in the mentioned state areas on the coasts of the Atlantic, the Caribbean Sea and the Gulf of Mexico, however such measures should in no way result to pollution of the marine environment outside the named areas. Pollution from ships, land-based sources and pollution caused by dumping should be prevented, reduced and controlled in the areas listed, through the implementation of international rules and standards that are applicable and generally accepted and that have been established by international organizations that are competent. Pollution emergencies in the areas listed should be addressed and responded to, so as to effectively control or reduce the pollution. Contingency plans to respond to incidents that involve pollution or the threat of pollution should be developed and promoted.
Marine litter and the increase of plastics in oceans and seas is a global concern and not just one state or a few states because the shape and state in which oceans and seas are, affect the whole world. Marine litter not only affects the marine environment, but it also affects the economy and health, especially to the communities who live near or get their livelihoods from oceans and seas. States need work with each other especially at the regional level and they should also come up with legislations, regulations and policies that prevent and reduce the introduction of litter especially plastics to the marine environment. Such regulations, laws and policies should be implemented and enforced. States can implement the polluter pays principle, which will ensure that companies, people and ships found to use the ocean and sea as their dumping ground for wastes, clean up the polluted area at their own expense. Also, as it has been discussed earlier, the highest contributor to marine pollution is land-based sources and therefore this shows that a global framework is needed to address the pollution of marine areas from such sources because currently there is none.
Agenda 21, United Nations Conference on Environment and Development, Rio de Janeiro, Brazil, 3 to 14 June 1992
Basel Convention o the Control of Transboundary movements of Hazardous wastes and their disposal, date of adoption 22 March 1989 (entered into force on 5 May 1992)
Convention on the Prevention of Marine pollution by Dumping of wastes and other matter (London Convention), opened for signature on 29 December 1972 (entered into force 30 August 1975)
Convention on Biological Diversity, opened for signature 5 June 1992 (entered into force 29 December 1993)
Convention on the Conservation of Migratory Species of Wild Animals (Bonn Convention) (entered into force 1 November 1983)
Conference of the Parties to the Convention on the Conservation of Migratory Species of Wild Animals held in Bergen, Norway (November 2011)
FAO Code of conduct for responsible fishing www.fao.org/docrep/005/v9878e00.htm
International Convention for the Prevention of Pollution from Ships 73/78 (MARPOL) (entered into force 2 October 1983)
Plan of Implementation of the World Summit on Sustainable Development, Johannesburg, (2002) www.un.org/esa/sustdev/documents/WSSD_POI_PD/English/WSSD_PlanImpl.pdf
The Global Programme of Action for the Protection of the Marine Environment from Land-bases Activities (adopted 5 November 1995)
United Nations Convention on the Law of the Sea, opened for signature on 10 December 1982 (entered into force 16 November 1994)
United Nations Fish stocks Agreement, opened for signature on 4 December 1995, (entered into force 11 November 2001) www.unorg/depts/los/convention_agreements/texts/fish_stocks_agreement/CONF164_37.htm
Convention for the Protection and Development of the Marine Environment of the Wider Caribbean Region (The Cartagena Convention), adopted in Cartagena, Colombia on 24 March 1983 (entered into force on 11 October 1986)
UNEP. Marine litter: a Global Challenge, Nairobi, 2009
UNEP. Biodegradable Plastics and Marine Litter: Misconceptions, concerns and impacts on marine environments. United Nations Environment Programme (UNEP), Nairobi (2015)
Department of the Environment and Energy, Australian Government, Threat abatement plan for the impacts of marine debris on vertebrate marine life, Marine publications and resources (May 2009)
Second intergovernmental review meeting of the Global Programme of Action for the Protection of the Marine Environment from Land-based Activities (GPA): A backgrounder. www.stakeholderforum.org/fileadmin/files/BriefingPaper1.pdf
Center for Biological diversity. Ocean plastics pollution: A global tragedy for our oceans and sea life www.biologicaldiversity.org/campaigns/ocean_plstics/
How pollution affects coral reefs https://celebrating200years.noaa.gov/visions/coral/side.html
UN News Centre: New UN report finds marine debris harming more than 800 species, costing countries million (5 December 2016) www.un.org/apps/news/story.asp?NewsID=55724
University of Exeter. The Impact of micro plastics on marine life www.exeter.ac.uk/research/feature/microplastics