UNEP/IOC Guidelines on Survey and Monitoring of Marine Litter.

Abstract

Globally our awareness of both the pervasiveness and magnitude of marine litter and the associated environmental and social problems is growing (Ribic et al. 1992, ANZECC 1996a, GESAMP 2001, Kiessling 2003, Cho 2005, UNEP 2005, OSPAR 2006, HELCOM 2007). This growth in knowledge is being paralleled by a concomitant increase in the number and scope of national and international marine litter investigations and assessment programmes. The objectives underpinning these litter assessment programmes are quite diverse with groups/organizations variously targeting increased public awareness, better understanding of the risks and impacts of litter, more understanding of litter sources and sinks to support improved management and not the least, cleaner waterways and beaches at local, regional, national and international scales. This variety in the purpose of assessment programmes is matched by the diversity in the operational structure of those programmes. Regardless of the underpinning motivation, marine litter investigations will generally fall into one of three basic types: 1) Beach litter surveys. 2) Benthic litter surveys, which include: a) Observations made by divers, submersibles or camera tows. b) Collection of litter via benthic trawls. 3) Floating litter surveys, which include: a) Observations made from ship or aerial based platforms. b) Collection of litter via surface trawls. Ultimately, to effectively manage and thereby mitigate the impacts from marine litter, there is a need to develop a good understanding of the problems and specifically to increase our knowledge about the principle types and sources of litter and the behaviours that result in litter entering the marine environment. To achieve this aim, there is a need to ensure that good quality data are available that will allow comprehensive analyses of the nature and sources of litter in marine environments and how these vary through time and in response to management interventions. In spite of growing interest and a mounting body of evidence from research and surveys, it is widely accepted that a major factor that limits our knowledge of (and therefore the ability to manage) marine litter results from inconsistencies in the design and delivery of sampling and assessment programmes. These inconsistencies largely result from a lack of consistent objectives and litter classification systems between alternative monitoring programmes (Ribic et al. 1992, ANZECC 1996a, Cheshire and Westphalen 2007). There is a growing need to develop standardized operational guidelines for marine litter survey and monitoring programmes so that litter levels on our beaches and within our seas and oceans can be estimated and interpreted through long-term, broad scale comparative studies that will support management at both national and international scales. Similarly, given that marine litter management ultimately relates to social and behavioural changes, there is a need to develop or maintain public awareness and education through simpler, less rigidly structured, programmes. Objectives The objectives for this study were to develop a set of standardized operational guidelines for the conduct of beach, benthic and floating litter assessments. In working to achieve this outcome it became clear that there was also a need to address the different underlying purposes, particularly in relation to beach litter assessments, and to that end we have developed two classes of surveys: 1) Comprehensive surveys for beach, benthic and floating marine litter These protocols are targeted at the collection of highly resolved data to support the development and/or evaluation of mitigation strategies in coastal and marine systems. The protocol for these surveys includes a highly structured framework for observations at regional, national and international scales. EXECUTIVE OVERVIEW 2 2) Rapid surveys for beach litter This protocol comprises a simplified version of the comprehensive beach survey, targeted primarily at developing public awareness and education about marine litter issues and is thus not constrained by the need to fit within a broader spatio-temporal comparison framework. Such surveys may be used as a vehicle for broader based community engagement and in building community capacity when working towards inclusion within the comprehensive survey framework. In developing the guidelines marine litter was defined as any waste, discarded or lost material, resulting from human activities, that has made it into the marine environment, including material found on beaches or material that is floating or has sunk at sea. Some organic materials (e.g. faeces or food waste) have been explicitly excluded and we do not include naturally sourced materials such as vegetation (e.g. seagrass wrack, algae or river sourced trees and branches). Organic materials have only been inc