Marine Debris Monitoring and Assessment:

Recommendations for Monitoring Debris Trends in the 

Marine Environment

NOAA Marine Debris Program

National Oceanic and Atmosphereic Administration

U.S. Department of Commerece

Technical Memorandum NOS-OR&R-46

November 2013

Photo taken by U.S. National Park Service, Kenai Fjords National Park
Mention of trade names or commercial products does not constitute 

endorsement or recommendation for their use by the United States 

government.
Marine Debris Monitoring 

and Assessment 

Recommendations for Monitoring Debris 

Trends in the Marine Environment 

Sherry Lippiatt1,2, Sarah Opfer2,3, and Courtney Arthur1,2

1 I.M. Systems Group; Rockville, MD, USA 

2 U.S. National Oceanic and Atmospheric Administration, Marine Debris Program; 

Silver Spring, MD, USA 

3

Earth Resources Technology; Laurel, MD, USA 

The suggested citation for this document is: 

Lippiatt, S., Opfer, S., and Arthur, C. 2013. Marine Debris Monitoring 

and Assessment. NOAA Technical Memorandum NOS-OR&R-46. 

For copies of this document, please contact: 

NOAA Marine Debris Division 

1305 East-West Highway 

Silver Spring, MD 20910 USA 
ii 

Contents 

EXECUTIVE SUMMARY ............................................................................................................ 1

1.0 INTRODUCTION ............................................................................................................... 2

1.1 Objectives and Method Development................................................................................................ 3

1.2 Debris Classification ............................................................................................................................ 4

1.3 Safety ..................................................................................................................................................5

2.0 SHORELINE METHODS ................................................................................................... 7

2.1 Debris Assessment Methods............................................................................................................... 7

2.2 Standing‐stock surveys........................................................................................................................ 8

2.3 Accumulation surveys......................................................................................................................... 9

2.4 Survey Design....................................................................................................................................10

2.4.1 Site Selection.............................................................................................................................. 11

2.4.2 Sample Frequency...................................................................................................................... 11

2.5 Equipment.........................................................................................................................................11

2.6 Pre‐Survey Shoreline Characterization ............................................................................................. 12

2.7 Shoreline Survey Methodology for Macro‐Debris (>2.5 cm)............................................................ 13

2.8 Sampling for Meso‐ (5 mm – 2.5 cm) and Micro‐Debris (≤5 mm).................................................... 16

2.9 Quality Control..................................................................................................................................17

2.10 Considerations ................................................................................................................................18

3.0 SURFACE WATER METHODS ...................................................................................... 19

3.1 Floating debris survey techniques .................................................................................................... 19

3.2 Survey Design....................................................................................................................................20

3.2.1 Site Selection.............................................................................................................................. 20

3.2.2 Sample Number and Frequency ................................................................................................ 21

3.3 Equipment.........................................................................................................................................22

3.4 Pre‐Survey Site Characterization ...................................................................................................... 23

3.5 Surface Water Trawl Survey Methodology (> 0.30 mm) .................................................................. 24

3.5.1 Trawling technique ........................................................................................................................ 24

3.5.2 Sample Processing ......................................................................................................................... 25
iii 

3.6 Data analysis .....................................................................................................................................26

3.7 Quality Control..................................................................................................................................26

3.8 Considerations ..................................................................................................................................27

3.8.1 Survey design ............................................................................................................................. 27

3.8.2 Technique...................................................................................................................................27

3.8.3 Data analysis .............................................................................................................................. 28

3.8.4 Relevance...................................................................................................................................28

4.0 AT-SEA VISUAL SURVEY METHODS ........................................................................ 30

4.1 Background .......................................................................................................................................30

4.2 Survey Design....................................................................................................................................31

4.3 Equipment.........................................................................................................................................31

4.4 At‐Sea Visual Survey Technique........................................................................................................ 31

4.5 Considerations ..................................................................................................................................33

5.0 BENTHIC METHODS ...................................................................................................... 34

5.1 Background .......................................................................................................................................34

5.2 Survey Design....................................................................................................................................35

5.2.1 Site Selection.............................................................................................................................. 35

5.2.2 Sample Frequency...................................................................................................................... 35

5.3 Shallow Environments (< 20 m) ........................................................................................................ 35

5.4 Continental Shelves (up to 800 m).................................................................................................... 36

5.5 Deep Sea Floor..................................................................................................................................37

5.6 Considerations ..................................................................................................................................38

6.0 REFERENCES .................................................................................................................. 39

7.0 APPENDICES ................................................................................................................... 47

7.1 Literature Review Tables................................................................................................................... 48

7.2 Shoreline Survey Advisory Group ..................................................................................................... 51

7.3 Versar, Inc. Executive Summary........................................................................................................ 52

7.4 Random Number Tables ................................................................................................................... 54

7.5 Data sheets .......................................................................................................................................56

7.6 Marine Debris Survey Photo Manual................................................................................................ 69

7.7 Frequently Asked Questions for Shoreline Surveys.......................................................................... 77
1 

EXECUTIVE SUMMARY 

Marine debris is defined by the National Oceanic and Atmospheric Administration (NOAA) and 

the United States Coast Guard (USCG) as any persistent solid material that is manufactured or 

processed and directly or indirectly, intentionally or unintentionally, disposed of or abandoned 

into the marine environment or the Great Lakes (33 USC 1951 et seq. as amended by Title VI of 

Public Law 112-213). Marine debris has become one of the most recognized pollution problems 

in the world’s oceans and waterways today. 

In recent years, research efforts have significantly increased knowledge of the topic of marine 

debris. However, the field as a whole has not adopted standardized monitoring procedures or 

debris item categories. Standard methodology and reporting is necessary in order to compare 

marine debris source, abundance, distribution, movement, and impact data on regional, national, 

and global scales. 

The NOAA Marine Debris Program (MDP) has developed standardized, statistically valid 

methodologies for conducting rapid assessments of the debris material type and quantity present 

in a monitored location. The monitoring guidelines in this document focus on abundance, types, 

and concentration rather than analyzing by potential source, as in many cases it is very difficult 

to connect a debris item to a specific debris-generating activity. These techniques are intended to 

be widely applicable to enable comparisons across regional and global scales. 

This document includes guidelines for estimating debris concentrations on shorelines, in surface 

waters, during visual surveys at sea, and in the benthos. Background information is provided for 

each environmental compartment (i.e., shorelines, surface waters, and the seafloor), in addition 

to guidelines for survey design, required equipment, the survey techniques, and study 

implementation considerations. The appendices include a brief literature review for each 

compartment, survey data sheets, a debris item photo guide, frequently asked questions for 

shoreline surveys, and a summary of work completed by Versar, Inc. to test the methodologies. 

The techniques described in this document were developed over the course of a number of years, 

based on a review of the literature, discussions with experts, and field testing by the MDP and 

contractors. For shoreline monitoring, the MDP benefited from feedback from partner 

organizations who implemented these methods prior to the official publication of these 

guidelines. 

The guidelines in this document are intended for use by managers, researchers, citizen scientists, 

and other groups conducting marine debris survey and assessment activities, especially those 

requiring a rapid assessment. Monitoring and assessment of marine debris is essential to 

understanding the problem and being able to mitigate, prioritize, and prevent the most severe 

impacts. The effort to develop this document was rooted in the need to standardize 

methodologies and facilitate comparisons across time, space, and environmental compartments. 

These guidelines are provided to the marine debris community at large in order to guide the 

development of integrated monitoring programs nationwide. 
2 

1.0 INTRODUCTION 

Marine debris, in some form, has been addressed by NOAA since the early 1980s and officially 

recognized as a problem by the federal government since the passing of the Marine Plastic 

Pollution Research and Control Act (MPPRCA) in 1987 (Public Law 100-220, Title II). This 

legislation was one of the first to provide research prioritization and authorize federal funding for 

marine debris in the United States. The NOAA Marine Debris Program (MDP) was initiated as a 

program in 2005 within the National Ocean Service’s Office of Response and Restoration and 

was legally established by the Marine Debris Act (33 U.S.C. 1951 et seq., as amended by Title 

VI of Public Law 112-213). The act provides specific mandates to the program including 

mapping, identification, impact assessments, removal and prevention activities, research and 

development of alternatives to gear posing threats to the marine environment, and outreach 

activities. 

Standardized marine debris monitoring and assessment can be used to evaluate the effectiveness 

of policies to mitigate debris, such as recycling incentives or extended producer responsibility 

measures, and provide insight into priority targets for prevention and mitigation (NRC 2008). 

For example, in the Gulf of Alaska, the NOAA Alaska Fisheries Science Center conducted 

shoreline monitoring prior to and following the implementation of the International Convention 

for the Prevention of Pollution from Ships (MARPOL); results indicated a significant decrease in 

the abundance of derelict fishing gear debris, in the form of nets from ships (Maselko and 

Johnson, 2011). Similarly, debris monitoring in Washington DC and other areas with recentlyenacted policies on single-use shopping bags are indicating fewer plastic bags in rivers and in 

riverine “trash traps” (e.g., Anacostia Watershed Society, unpublished data). 

The complicated nature of the distribution of marine debris in the environment calls for a clear 

and defined approach to characterizing and assessing the problem. Marine debris enters the 

marine environment through many pathways, and the extensive size of the ocean, patchiness in 

the distribution of debris, and spatial and temporal variability in the drivers of debris add to the 

complex life cycle of marine debris (Ryan et al., 2009, Cole et al., 2011, Doyle et al., 2011). This 

document updates and expands upon marine debris assessment guidelines developed by the 

NOAA Marine Entanglement Research Program in 1992 (Ribic et al., 1992). The guidelines 

outlined here incorporate modern technologies and sampling equipment and focus on 

standardization of data and reporting for a statistically robust analysis which can address all 

types of debris. Guidelines are included for estimating debris concentration on shorelines, in 

surface waters, during visual surveys at sea, and in benthic surveys. The shoreline survey 

technique described here is available in a user-friendly version in the NOAA Shoreline Survey 

Field Guide (Opfer et al., 2012). 
3 

1.1 Objectives and Method Development 

The guidelines in this document are intended to serve as a basis for nationwide monitoring and 

assessment of marine debris, and were designed with four main objectives in mind: 

 Estimate the quantity of debris at local and regional levels according to land use or other

correlating parameter

 Determine types and concentration of debris present by material category (plastic, metal,

glass, rubber, paper/processed lumber, cloth/fabric, other)

 Examine the spatial distribution and variability of debris

 Investigate temporal trends in debris types and concentration

This report includes guidelines for four survey techniques developed and/or modified by the 

MDP: 

 Shoreline techniques: Guidance for assessing debris concentration on shoreline segments,

including both macro- (> 2.5 cm) and meso-debris (5 mm–2.5 cm)

 Surface water techniques: Guidance for assessing floating debris concentration, including

macro-debris (>2.5 cm), meso-debris (5mm–2.5cm) and micro-debris (≤ 5 mm in length)

 At-sea visual techniques: Guidance for conducting ship-based visual surveys of floating

macro-debris (> 5cm or 2 in)

 Benthic techniques: Guidance for evaluating debris concentration on the seafloor

The methods detailed in this report take into consideration lessons learned from studies listed in 

Section 7.1. Additionally, shoreline methods were developed with input from an established 

advisory group. The advisory group consisted of established researchers in the debris monitoring 

field, other federal agencies involved in marine debris efforts, and internal NOAA MDP staff 

(Section 7.2). 

The techniques for shorelines, surface waters, and at-sea visual surveys were tested and refined 

by NOAA MDP staff during a pilot project in summer and fall 2009 - 2010 in the Chesapeake 

Bay (Arthur et al., 2011). In 2011, the refined techniques were used during monthly surveys in 

various tributaries of the northern Chesapeake Bay to test the hypothesis that debris 

concentration is correlated with land-use (Lippiatt et al., 2012). Additionally, rigorous bi-weekly 

shoreline and surface water sampling completed by Versar, Inc. from July through December 

2011 at two sites in the mid-Atlantic informed statistical considerations described in Sections 2.0 

and 3.0 of this document. The shoreline technique was also extensively used and tested by 

regional and local groups along the U.S. west coast, Alaska, and Hawaii to monitor for the 

arrival of marine debris generated by the 2011 Japanese tsunami. 

In 2009, the United Nations Environment Program (UNEP) published a debris assessment 

framework with the major goal of management and integration of debris monitoring activities 

across broad geographic regions (Cheshire et al., 2009). The UNEP framework includes a set of 

survey methods for beach, benthic, and floating debris assessment based on existing techniques 

used in the Oslo and Paris Convention for the Protection of the Marine Environment of the 
4 

North-East Atlantic (OSPAR), the Northwest Pacific Action Plan (NOWPAP), Australian 

Marine Debris Status (AMDS), and the National Marine Debris Monitoring Program (NMDMP) 

(Cheshire et al., 2009). The approach taken in this document is modeled after UNEP’s 

framework with a few key differences: NOAA techniques focus on item count and concentration 

(in units that count debris items per square meter of shoreline, # items/m2) rather than both count 

and weight information; NOAA shoreline survey techniques focus on assessment of debris 

standing-stock rather than flux rate (however, the NOAA shoreline survey can be adapted for 

accumulation surveys, see discussion in section 2.0, below); and the debris classification systems 

vary between the two methods. 

The application of these guidelines to discrete studies will be most informative when study 

design and site selection address clearly stated objectives. 

1.2 Debris Classification 

Although previously published guidelines have focused on documenting the primary source of 

debris (e.g., Sheavly, 2007), the methods described here emphasize material type. 

Debris source information is an excellent educational tool, however many debris items are 

difficult to identify as either land- vs. sea-based or industrial- vs. consumer-based debris. The 

source of a piece of debris found in the open ocean cannot necessarily be attributed to the 

manufacturing origin or country of consumption. Even when the debris has markings that can be 

used to identify where it was produced, the exact point of loss to the environment is unknown. 

Original sources of floating marine debris in the oceans can be difficult to identify, given the 

persistence and potential for long-range transport of lightweight buoyant materials (Ryan et al., 

2009).This makes it difficult to evaluate controls on the land- or ocean-based sources of marine 

debris. Guidelines in this document take a tiered approach whereby every piece of debris is 

recorded according to material category and then by specific item or product (as recommended in 

Ribic et al., 1992). The material categories included are plastic, metal, glass, rubber, 

paper/processed lumber, cloth/fabric, and other or non-classifiable debris. There is also the 

allowance of “other” items that are locally important and may not be currently listed on the data 

sheets. Further, these items can be catalogued and tracked in the www.md-map.net online 

database (see Section 2.6). In this way, these guidelines allow for regional customization of 

important debris items. Information on debris source can be obtained during data analysis if 

indicator items are identified (e.g., plastic fishing floats are assumed to be sea-based debris). 

Furthermore, this approach enables analysis of variability in the composition and quantity of 

debris over time and space. The NMDMP effort (described in further detail in section 2.0), which 

collected information on specific indicator items, was designed to evaluate debris trends on a 

regional scale and was not suitable to local-scale assessments of spatial and temporal variability 

in debris types and quantities (Sheavly, 2007, NRC 2008, Ribic et al., 2010, Sheavly, 2010, 

Ribic et al., 2011, Ribic et al., 2012). 

The methods described here do not include debris weight information. Debris weight can be 

challenging to measure and dependent on water content; reporting in units of debris counts (e.g., 
5 

#items/m2 of shoreline or #items/m3

 of water) provides more reliable and consistent data and 

techniques that are more accessible to organizations that may not have means of accurately 

weighing debris. Other programs that are not meant to be part of a rapid response technique or 

wish to factor in how physical properties such as weight, density, and form affect debris 

hydrodynamics and fate, may want to collect weight data. 

Debris items encountered during these surveys is differentiated based on size class. Both the 

shoreline and surface water sampling strategies distinguish between large (>30cm) and small 

debris items (<30cm). Large debris items have a larger surface area and therefore have a greater 

potential to disturb valuable habitat. Additionally, large debris items may be less mobile in the 

environment and may be encountered more than once in reoccurring surveys. Having a record 

and location of these items will limit the potential errors in duplication. Figure 1, below, 

indicates the debris size ranges sampled by the techniques described here. 

Figure 1. Size ranges sampled by the techniques suggested in this document. 

1.3 Safety 

Safety should be the number one priority during any survey activity. Because this work is carried 

out in the field, there are inherent hazards associated with these techniques. Use caution and 

follow general safety guidelines. The safety tips below are provided as general guidance, but it is 

imperative that project leads understand all risks associated with survey activities, always use 

caution, and conduct an operational risk assessment for the specific marine debris survey activity 

and location. Operational risk assessments should include resources (e.g., equipment, boats, 

communication, support, personal protective equipment), environmental hazards or 

considerations (e.g., remoteness, surf zones), personnel (experience, training, physical and 

mental fitness), weather, and mission complexity. 

 Follow the buddy system when conducting shoreline surveys and other field operations.

 Let someone know where you are and when you expect to return.

 Carry a means of communication for emergencies, for example a cell phone or radio. If

there is no reception use a GPS emergency responder or personal locator beacon.
6 

 Always carry a first aid kit. The kit should include an emergency water supply and 

sunscreen, as well as bug spray. 

 Understand the symptoms of heat stress and actions to treat it. For more information, see 

the OSHA website (https://www.osha.gov/SLTC/heatstress/heat_illnesses.html). Make 

sure to carry enough water.

 Be prepared for the weather and tides. Do not conduct field operations in severe weather 

and when tides could impede the survey area or block an access route. 

 Wear appropriate clothing. Be sure to wear close-toed shoes and gloves when handling 

any non-hazardous debris as there may be sharp edges.

 Be aware of your surroundings and be mindful of trip and fall hazards.

 While on a vessel, always wear your life jacket and make sure it fits correctly.

 Large, heavy objects should be left in place. Do not attempt to lift heavy debris objects as 

they may have additional water weight and lifting them could result in injury.

 If you are conducting surveys in the United States and you come across a potentially 

hazardous material (e.g., oil or chemical drums, gas cans, propane tanks), contact local 

authorities (a 911 call), a state emergency response or environmental health agency, and 

the National Response Center at (1-800-424-8802) to report the item with as much 

information as possible. Do not touch the material or attempt to move it.

 When in doubt, don’t pick it up! If unsure of an item, do not touch it. If the item is 

potentially hazardous, report it to the appropriate authorities.
7 

2.0 SHORELINE METHODS 

Marine debris monitoring on shorelines has become an increasingly common undertaking for 

academic, government, and environmental organizations. Shoreline surveys are usually more 

accessible, inexpensive, and straight-forward than monitoring in other environmental 

compartments. Often the highest debris concentrations are found on shorelines, which facilitates 

data analysis and trend assessment. 

In addition to lessons learned from the studies listed in Section 7.1 and described below, these 

methods were developed with input from an established advisory group. The advisory group 

consisted of researchers in the debris monitoring field, other federal agencies involved in marine 

debris efforts, and NOAA MDP staff (Section 7.2). Data sheets modified here (Section 7.5) were 

adapted from UNEP and the Intergovernmental Oceanographic Commission (UNEP/IOC) debris 

monitoring guidelines (Cheshire et al., 2009). 

2.1 Debris Assessment Methods 

Numerous marine debris monitoring programs exist throughout the world. Most programs have 

unique objectives and employ a variety of region-specific methodologies, making across the 

board comparisons of debris estimates difficult (e.g., Barnes et al., 2009). For shorelines, some 

studies report number (or weight) of debris items per unit length of shoreline (e.g., Bowman et 

al., 1998, Barnes and Milner, 2005) or strandline (e.g., Velander and Mocogoni, 1999) while 

others report number (or weight) of items per unit area of shoreline (e.g., Acha et al., 2003). 

In addition to the NOAA Marine Entanglement Research Program guidelines mentioned above 

(Ribic et al., 1992), lessons learned from previous marine debris monitoring efforts were 

considered during development of these guidelines. One key long-term, large scale monitoring 

program, the National Marine Debris Monitoring Program (NMDMP), was developed by an 

interagency working group consisting of the U.S. Environmental Protection Agency, NOAA, 

National Park Service, and United States Coast Guard following the ratification of MARPOL 

Annex V and the passage of the MPPRCA. NMDMP was designed to assess the magnitude of 

the marine debris problem in the U.S. and evaluate any regional or temporal trends according to 

a statistically valid design and sampling plan (Escardó-Boomsa et al., 1995). The NMDMP 

study, which consisted of monthly surveys conducted by trained volunteers at randomly selected 

sites along the U.S. coastline, used indicator items to identify the major sources of debris 

(Sheavly, 2007). Monitoring occurred from 1996 to 2006 and an analysis of data from a five year 

time period (2001 – 2006) is provided in Sheavly (2007). The five year analysis showed no 

statistical change in the prevalence of the indicator items for the nation as a whole (regional data 

analyses are found in Ribic et al. (2010), Ribic et al. (2011), and Ribic et al. (2012)). 

This NOAA shoreline survey technique is designed as a rapid, quantitative beach assessment for 

collection of standardized and consistent data that can be applied to address policy and 

management needs at various spatial scales. The UNEP framework mentioned above (Cheshire 

et al., 2009) provides two different beach survey techniques – comprehensive and rapid beach 
8 

assessments. This NOAA shoreline technique is designed to be useable by trained community 

volunteer organizations while simultaneously providing data that can be used to address key 

management questions. Table 1 provides a comparison of the two survey techniques. 

UNEP NOAA

Removal of shoreline debris? Yes No/Yes*

Report item count or weight? Both Count only

Shoreline site length 100 – 1000 m 100 m sections 

Site characterization included? Yes Yes

Minimum debris size 2.5 cm 2.5 cm 

Recommended survey frequency At least every 3 months Every 28 days +/- 3 days 

Smaller item protocol? 10-m wide transects Sieve protocol 

Large items recorded separately? Yes Yes

Specialized equipment required? Scale for weight No 

Table 1. Comparison of NOAA and UNEP shoreline survey guidelines. 

* NOAA standing-stock techniques can be adapted for shoreline cleanup efforts. See Section 2.3, below.

2.2 Standing-stock surveys 

The shoreline technique described in this document is designed as a standing-stock assessment 

survey. Standing-stock surveys are used to measure the load or concentration of debris at a 

shoreline site over time. Each survey event is a snapshot of the concentration of debris at the site, 

and a series of these snapshots over time provides information on changes in the baseline 

concentration of debris. Knowing the concentration of debris (in units of #items/m2

 of shoreline) 

at various shoreline sites is necessary in evaluating the cumulative impact and conducting impact 

or risk assessments of debris at a given site and on a regional scale. In standing-stock surveys, 

the measured debris concentration reflects the long-term balance between inputs (land and sea 

based) and removal (through export, burial, degradation, etc.). An understanding of how the 

abundance of debris changes over time facilitates analysis of the drivers of debris deposition 

(e.g., weather, tides, tourism, prevention efforts). 

In order to obtain a valid time-series of debris concentration, the natural flux of debris onto and 

off of the shoreline should not be altered by the survey activity. Integrity of the sample design 

should be maintained by not removing debris from the site during standing-stock surveys. If 

debris is removed from the shoreline site during a survey, the overall abundance of debris may 

be underestimated at subsequent surveys. Exceptions should be considered if an item poses a 

threat to human health or is potentially hazardous. 

The standing-stock and residence time of marine debris on a given shoreline will vary with 

characteristics of the debris itself, deposition from land- and sea-based sources, local climate and 

seasonal weather patterns, and characteristics of the beach itself. Shoreline geomorphology, 

substrate, exposure, and coastal current patterns are some of the factors that will affect whether a 

given site tends to accumulate or capture debris. 
9 

2.3 Accumulation surveys 

The shoreline survey technique described here can be modified for accumulation surveys (see 

Opfer et al., 2012). During accumulation surveys, marine debris is removed from the shoreline 

site. Accumulation studies require initial removal of all debris from the site followed by regular 

surveys to record and remove all debris. Because debris is removed from the site, the data 

collected over time provides an estimate of the flux of debris onto the shoreline (in units of 

#items/m2/time), as opposed to the concentration or standing-stock of debris. Both types of data 

are useful for developing models of the life cycle and movement of debris among environmental 

compartments. Accumulation survey data indicate the net flux of debris onto the shoreline, and 

assume that the rate of debris accumulation is uniform between sample events. Debris flux data 

can be used to assess changes in at-sea debris loads, but cannot be used to evaluate the debris 

load or cumulative impacts of debris. Compared to standing-stock surveys, accumulation studies 

require more time and money as they are more thorough, require debris removal, and need to be 

conducted on a more frequent basis. 

 

Accumulation survey frequencies must be identical for comparison between studies (Ribic et al., 

1992). Shoreline sites may have a relatively rapid debris turnover rate, so in order to accurately 

estimate debris flux onto a shoreline site it must be sampled frequently. There is growing 

evidence that accumulation rates are underestimated by typical survey frequencies. Eriksson et 

al. (2013) found that daily accumulation rate measurements (i.e., surveys conducted on a daily 

basis) were an order of magnitude higher than those measured during monthly surveys, and 

Swanepoel (1995) suggested that daily accumulation rates were 100-600% higher than weekly 

accumulation rates. Eriksson et al. (2013) further suggested that 12 days of consecutive sampling 

at a given site may be more informative than monthly surveys over the course of one year. 

However, Ryan et al. (2009) argue that longer intervals between sampling events reduces 

variability in measured accumulation rates. 

It is difficult to differentiate between factors that result in the deposition of debris onto the 

shoreline. Depending on the timing of sampling events (e.g., just prior to or following a storm 

event), the calculated net accumulation rate will likely vary. A debris marking study by Williams 

and Tudor (2001) found that “old” debris can reappear on the shoreline following strong wind 

events. Debris can become buried soon after deposition; in reality, accumulation studies are 

measuring the accumulation rate of visible debris items (Ribic et al., 1992). Accumulation data 

may also be affected by the lateral influx of debris from adjacent shoreline sites. Thus, 

conducting shoreline surveys may not be a suitable proxy for estimating debris loads in the 

ocean. 

Given these considerations, accumulation studies may be appropriate based on study objectives. 

For example, accumulation surveys can be used to look for a spike in debris deposition from a 

major debris-generating event or variations due to climactic events (e.g., El Niño Southern 

Oscillation; Morishige et al., 2007). Debris flux measurements are important to understanding 

the life cycle of marine debris, and accumulation surveys will provide information on the relative 

abundances of different debris types. To reduce the impacts of marine debris in critical habitats, 
10 

the benefit of more invasive accumulation surveys (with removal of debris) versus less intrusive 

standing-stock surveys should be considered in these locations. 

2.4 Survey Design 

Previous studies have shown that varying amounts and types of marine debris accumulate on 

shorelines depending on geographical location, oceanographic and meteorological conditions, 

climatological patterns (such as El Niño), and proximity to land-based or ocean-based sources 

(Morishige et al., 2007, Sheavly, 2007). To provide a more statistically relevant dataset, 

monitoring sites should be randomly selected from appropriate strata (e.g., land use, commercial 

and recreational fishing activities, political boundaries or management areas, storm water or 

sewage outfalls). Because there are various factors affecting debris deposition on shorelines, 

some studies have not detected significant differences in debris abundances between sites based 

on stratifying parameters. For example, van Cauwenberghe et al. (2013) found that sedimentary 

regime (i.e., accretion versus erosion) and tourism did not account for the debris loads they found 

on Belgian shorelines. Further, Versar, Inc. (2012) did not find differences in debris loads based 

on watershed land use. 

The amount of sampling necessary to assess debris concentrations within a given region is 

dependent on the spatial variability in debris concentrations and the desired level of detection 

(i.e., in order to detect a smaller change in debris load, more sampling is required). Versar, Inc. 

(2012) used a nested survey design to test the utility of the shoreline and surface water survey 

techniques described here, which were developed based on a 100-m length of shoreline. At the 

coarsest level, two regions in the coastal mid-Atlantic United States were selected based on land 

use (urban vs. rural). Within each region, three 1000-m locations (stretches of shoreline) were 

identified. Locations were required to meet all site selection criteria (listed below) and were 

separated by at least 1200 m. Within each location, three 100-m shoreline sites were 

systematically selected and remained fixed for the duration of the study. Surveys at the site level 

were conducted on a bi-weekly basis for a period of six months in accordance with the standingstock technique described below. Results of the study indicated that there was more variability 

(higher relative standard error) in debris concentrations among sites within a given location 

compared to the variability between locations at the regional level. This suggests that in order to 

decrease error in reported debris concentrations, shoreline surveys should be designed to assess 

debris at the scale of a 1000-m location (i.e., random selection of transects within a 1000-m 

location). 

However, this technique was designed to be widely applicable, and it is recognized that in some 

cases it is not possible to find a suitable 1000-m stretch of shoreline for location-level 

assessment. Further, the European Union / Joint Research Centre Marine Strategy Framework 

Directive (MSFD) recommends a study design that includes more than one 100-m site on a given 

stretch of shoreline, or two sections of 50-m on heavily littered shorelines (MSFD, 2013). The 

technique explained below is based on assessment of debris at one 100-m site, but it should be 

noted that a study that includes more than one site on a given shoreline will provide more 

statistically powerful results. 
11 

2.4.1 Site Selection 

An assessment of the impact of marine debris surveys on the local environment should be 

completed prior to commencement of any monitoring activities. In particular, monitoring should 

not be conducted where there is the potential for impacts to endangered or protected species or 

habitats. Organizations wishing to engage in marine debris monitoring activities are encouraged 

to contact local land owners or managers and wildlife authorities during the site selection 

process. 

Shoreline survey sites should have the following characteristics: 

 Sandy beach or pebble shoreline

 Clear, direct, year-round access (or seasonal access depending on physical conditions of

the site)

 No breakwaters or jetties that affect local circulation and accumulate or inhibit debris

deposition

 A minimum of 100 m in length parallel to the water (measured along the waters’ edge)

 No regular cleanup activities. Sites do not need to be precluded solely because of annual

or semi-annual cleanup events, but activities need to be tracked and noted in data analysis

These characteristics should be met where possible, but should be analyzed on a case-by-case 

basis and modified if appropriate for a particular region/location or shoreline type. The minimum 

length of shoreline was selected based on UNEP recommendations for rapid assessment 

(Cheshire et al., 2009). UNEP and MSFD (2013) suggest selecting shoreline sites that have a low 

to moderate slope (15 – 45o). Shallow tidal mudflat areas can be very wide at low tide, and 

marine debris is typically not very common in the intertidal. However, low-slope sites may still 

be appropriate for surveys. 

2.4.2 Sample Frequency 

Biweekly testing in the coastal mid-Atlantic indicated that in most instances, individual sampling 

events closely tracked monthly averages (Section 7.3). This finding suggests that sampling once 

every 28 days provides an accurate snapshot of debris concentration for the month. Following on 

recommendations from the National Marine Debris Monitoring Program (Sheavly, 2007), 

surveys should occur within a three-day window of the scheduled sampling event (i.e., shoreline 

standing-stock surveys should occur once every 28 ± 3 days). 

2.5 Equipment 

The following items are suggested for shoreline standing-stock assessments: 

 Digital camera

 Hand-held GPS unit

 Extra batteries (suggest rechargeable batteries)

 Surveyor’s measuring wheel

 Flag markers/stakes
12 

 100-foot measuring tape (fiberglass preferred) 

 First aid kit (to include sunscreen, bug spray, drinking water) 

 Work gloves 

 Sturdy 12-inch ruler 

 Clipboard for each surveyor 

 Data sheets (printed on waterproof paper) 

 Pencils 

 For meso- and microdebris assessment: 

o 5-mm stainless steel sieve 

o Stainless steel tweezers/forceps 

o 32-ounce (~1 L) amber glass sample bottles with lids 

o Wide-mouth funnel (stainless steel) to fit glass bottles 

o Plastic bucket 

o Quadrat kit (1 m2) 

o Small folding shovel 

o Waterproof paper for labels 

o Permanent markers 

2.6 Pre-Survey Shoreline Characterization 

Before any sampling begins, shoreline characterization should be completed for each 100 m site. 

Each survey site should be measured and marked for accuracy and repeatability using a 

surveyor’s measuring wheel. This includes recording GPS coordinates in decimal degree format 

(DDD.DDDD N/W) at the start and end of each 100 m segment (note that locations in the 

southern or western hemispheres will have negative latitudes or longitudes). If the shoreline 

width is greater than 6 m, GPS coordinates at all four corners of the shoreline section should be 

recorded where possible. Additionally, a shoreline ID name should be created and used for the 

duration of the study (this name will be used for reference in the www.md-map.net database1

). 

Shoreline characteristics and surrounding land-use characteristics (e.g. primary land use, nearest 

town, nearest river, etc.) should also be recorded on the data sheets prior to survey activity. 

Shoreline characteristics include identification and uniformity of the primary substrate type 

(sand, cobble, etc.), the tidal range and distance (if applicable), a description of the first barrier at 

the back of the shoreline section (dunes, vegetation, etc.), and the aspect of the shoreline. It is 

important to record the distance to outfalls, rivers, and other potential sources of marine debris as 

well as local current patterns which can affect debris deposition. Digital photographs should be 

taken to document the physical characteristics of the monitoring site. Unless major changes 

occur to the shoreline, shoreline characterization only needs to be completed once per site per 

year. As mentioned above, changes in beach morphology (e.g., as a result of storm activity) may 

result in changes in debris deposition. 

 

1

 At the time of publication, the NOAA MDP online database for shoreline survey data is housed at www.mdmap.net. The database allows users to create custom debris items within the existing NOAA datasheet framework 

and facilitates data export and analysis. For information or access to the database, email MD.monitoring@noaa.gov. 
13 

2.7 Shoreline Survey Methodology for Macro-Debris (>2.5 

cm) 

In order to analyze the maximum width of the shoreline section during a relatively rapid beach 

assessment, sampling should be conducted within three hours of low tide. This constraint is made 

for the following reasons: 

 Basing surveys on tides provides a consistent starting point at the waters’ edge. Wrack 

lines are inadequate reference points as they move and change throughout the year. 

 Some shoreline sites are inaccessible at high tide.

 Low tide heights typically exhibit less variability than high tides, which allows for a 

larger window of time to conduct surveys.

 Surveys conducted just prior to high tide may miss debris deposited on the wrack line at 

high tide.

 Surveying the entire shoreline (including the intertidal) at all sites facilitates comparisons 

of debris concentrations across sites. Data is representative of the entire shoreline site and 

is not biased by a small sample size (Rees and Pond, 1995; Burnham et al., 1985). 

 Low tide provides a simple gauge of area surveyed. If a survey team does not have the 

ability to measure beach width at a given survey, it may be a valid assumption that 

approximately the same area of shoreline is being surveyed (we highly suggest testing 

this for a given shoreline site prior to accepting this assumption).

Before arriving on site, select four numbers from the random number table (Section 7.4) to 

eliminate any bias from visual inspection of the shoreline section. These four numbers 

correspond with four transects of 5 m in length within the shoreline section that will be sampled 

at this particular survey. The number of transects chosen for each sampling event correspond 

with a 20% coverage of the shoreline section. Thus, on any sampling day 20 m of the 100 m 

shoreline section is analyzed for debris. 

Transects run perpendicular to the shoreline section from water’s edge, at the time of sampling, 

to the back of the shoreline (Figure 2). The back of the shoreline is defined as the location of the 

first barrier or primary substrate change. There might be a change in substrate within the 

intertidal zone; in this instance the back of the shoreline should be defined such that it extends to 

at least the high tide wrack line. Further, if there is evidence that storm or wave action is pushing 

debris beyond the back of the shoreline, surveyors may be interested in recording these debris 

items separately (e.g., in Alaska debris is commonly found in the wooded region behind the 

shoreline). In this case, debris beyond the back barrier is recorded on a second data sheet and 

tracked separately from debris on the shoreline. 

Upon arrival at the site at low tide, use the surveyor’s measuring wheel to mark the selected 

transects with flags and record transect GPS coordinates in decimal degree format. Depending on 

the width of the shoreline section, the coordinate information can be recorded either at one point 

in the middle of each transect (shoreline width <6 m or < ~19.5 ft) or at both the water’s edge 

and back of each transect (shoreline width >6 m or ~19.5 ft; Figure 2). This designation is due to 

the error associated with the operation of handheld GPS units. The GPS coordinates of each 

transect are recorded for quality assurance and to track any changes of beach morphology over 
14 

the course of the study. For surveys conducted at high latitude locations, include information on 

the GPS datum used in the notes section of the data sheet. In addition to GPS locations, record 

ancillary data prior to the debris survey, which includes the length of each transect from water’s 

edge to first barrier, the time, season, and date of last survey, description of recent storm activity, 

current weather conditions, and the number of individuals conducting the transect survey. If 

these characteristics are consistent between transects on a given survey event, they only need to 

be recorded on one data sheet. 

Figure 2. Shoreline section (100 m) displaying perpendicular transects from water’s edge at low tide to the first 

barrier at the back of the shoreline section. Red circles indicate marked GPS coordinates. Shoreline width 

determines location and number of GPS coordinates. Figure not to scale. 

Once ancillary data are recorded, surveyors should walk each transect tallying debris items 

according to material type and subcategory (see data sheets in Section 7.5). Debris items should 

only be recorded if they are at least 2.5 cm in size on the longest dimension (Figure 3). This 

standard length (approximately the diameter of a typical beverage bottle cap) was chosen to 

ensure that the same size items are counted across surveys and to maintain consistency in survey 

results. Data on debris < 2.5 cm has limited accuracy due to its small size compared to the 

transect area. In practice, surveyors will inevitably miss a significant fraction of debris below this 

size cutoff. This size cutoff for macro-debris surveys has also been adopted by UNEP (Cheshire 

et al., 2009) and the MSFD (MSFD, 2011, MSFD, 2013). Recognizing that small items represent 
15 

an important size fraction of marine debris that may pose an even greater threat to marine life 

(e.g., through ingestion), this technique suggests the use of subsampling within transects for the 

assessment of meso- and micro-debris. The challenges with this approach, given the variability 

in small debris concentrations within a shoreline transect, are discussed below. 

Figure 3. The minimum debris size to be counted is 2.5 cm. 

Large macro-debris items (> 30 cm or about 1 ft) are recorded on a separate section of the debris 

data sheet. Large items should only be recorded in the large items section. Information recorded 

should include the debris type, the status of the large item (sunken, stranded, or partially buried), 

the latitude and longitude of the item, and the approximate debris size. This information is 

important in determining the footprint of large debris items. 

Any item that is partially within a transect should be tallied (however, items should not be tallied 

twice if randomly selected transects are adjacent). If an item is blown into a transect mid-survey, 

it is tallied only if the surveyor has not yet surveyed the section of the transect where the item is 

located. Multiple fragments of what may have originally been a whole item should be tallied 

separately. Capturing information on the total number of fragments present is a better reflection 

of the debris impacts and effort required for cleanup. If one fragment is recognizable as a 

specific item, for example a remnant of a plastic beverage bottle, it should be recorded as such 

provided that the remnant is at least 50% of the original item (Tangaroa Blue Foundation, 2012). 

Items that do not fall under a specific subcategory can be entered into the “other” category at the 

end of each material section. In order to ensure that these standardized methods are widely 

applicable, NOAA’s online shoreline survey database allows users to create custom debris 

categories1

. This allows researchers to track locally-relevant debris items within a nationallystandardized format. 

If a surveyor is unsure of an item’s material type, it is tallied in the other/non-classifiable 

category at the end of the data sheet. Include a brief description of the item in the notes section 

for clarification. Items that are composed of multiple material types should be recorded 

according to the most abundant material that makes up the surface of the item. For example, a 

tire with a metal rim would likely be recorded as a large rubber item. A debris item photo guide 

is included in Section 7.6. Digital photographs should be taken of unidentifiable items, as well as 

other debris items or markings of interest. Place a lined ruler next to the debris item to establish a 

size reference. It is also a good practice to take a photo of each transect surveyed, and record 

photo ID numbers on the data sheet. 

 
16 

The macro-debris item concentration (number of debris items/m2

) per transect is calculated as 

follows: 

ൌ ܥ

݊

ሺݓൈ݈ሻ

C = concentration of debris items (# of debris items/m2) 

n = # of macro-debris items observed 

w = width (m) of shoreline section recorded during sampling (i.e, transect width) 

l = length (m) of shoreline sampled = 5 m 

Note that the shoreline width that is measured at each transect is essential for calculating debris 

concentrations. For a given sampling event: 

1. Calculate debris concentrations for each individual transect surveyed (a minimum of four 

per survey). 

2. Take the mean of the concentrations at each transect to calculate an overall site 

concentration (± standard deviation) for that date. 

The previously mentioned online database exports survey data (counts) and concentrations per 

debris item category, material type, large debris, and total debris. 

2.8 Sampling for Meso- (5 mm – 2.5 cm) and Micro-Debris 

(≤5 mm) 

Random samples can be collected from sandy beach locations for analysis of meso- and microdebris. For random sampling within a shoreline segment, use a random number table (Section 

7.4) to select the placement of a 1-m2 quadrat. The placement of the number on the random 

number table determines the location of the sample. For example, if random number seven was 

chosen, the placement of the quadrat would be on the right side of the transect in the wrack line. 

Because shoreline meso- and micro-debris concentrations are very patchy, random quadrat 

placement may not always be the preferred method. During field testing in the coastal midAtlantic, meso-debris was very rare in randomly selected samples (meso-debris occurred in only 

2-3% of sample events; Versar, Inc. 2012). Therefore, depending on study objectives, it may be 

appropriate to focus meso-debris sampling on sections of the shoreline where small debris is 

more likely to accumulate. Previous studies have suggested sampling along the wrack line, 

where less re-suspension and thus higher debris concentrations are expected to occur, and to 

avoid the effect of tidal height on the deposition of debris of various sizes and densities (Browne 

et al., 2010). Van Cauwenberghe et al. (2013) found significantly higher concentrations of 

microplastic at the high-water mark compared to the low-water mark on Belgian shorelines. 

However, if samples are collected in a non-random fashion (i.e., focused on the wrack line), 

results cannot be extrapolated over larger spatial scales. 
17 

Figure 4. Randomly placed 1 m2 quadrat with area of sand to be sieved (0.0625 m2) in bold. 

Once the quadrat placement is selected, remove any pieces of debris from the surface that are 

larger than 2.5 cm (and should have been counted in the macro-debris survey). Use a small 

stainless steel shovel to collect the top 3 cm of sand from 1/16 of the quadrat (0.0625 m2). This 

is done by dividing the quadrat into fourths and then dividing one of the quarters into fourths 

(Figure 4). Sieve the collected sand through a stainless steel 5 mm mesh sieve above a bucket or 

funnel and sample jar. If the sand is wet, use a water rinse to facilitate the sieving process 

(seawater that has been sieved through a 0.33-mm screen is sufficient for this purpose). Transfer 

the sieved micro-debris samples to labeled amber glass bottles for further analysis back in the lab 

(Baker et al., 2013). If it is not possible to properly identify meso-debris items (> 5 mm) in the 

field they should be collected and analyzed back in the lab. Repeat this process for each of the 

four transects that were sampled for macro-debris. 

Meso- and micro-debris item concentration (# of debris items/m3

) is calculated as follows: 

	ൌ ܥ

݊

ሺܽ ൈ ݄ሻ

C = concentration of debris items (# of debris items/m3) 

n = # of debris items observed 

a = area sampled = 0.0625 m2 

h = depth of sample = 0.03 m 

Provided that samples are collected randomly, meso- and micro-debris concentrations for a given 

sampling event can be calculated according to the same approach as for macro-debris (Section 

2.7).

2.9 Quality Control 
18 

To ensure that all of the appropriately sized debris items within a transect are recorded, quality 

control estimates should be conducted by a second surveyor before the collection of the mesoand micro-debris sample. The second surveyor should assess 20% of the total number of 

transects sampled per site over the course of the study (e.g., one site visited monthly will have a 

total of 48 transects and 10 quality assurance / quality control samples). Quality assurance 

sampling should be distributed among different sampling events and include consideration of 

debris classification. 

2.10 Considerations 

Shoreline surveys are the most accessible and cost-effective mode of marine debris monitoring 

and assessment. Depending on study objectives, additional data collection needs may be 

identified, for example debris location on the shoreline, number of beach visitors, or information 

on debris biofouling. This information can be included in the notes section of the data sheets or 

on a separate form. Surveys can be conducted by appropriately trained and managed volunteers 

to reduce costs, but as with any citizen-science effort, volunteer coordination is a major (and 

often overlooked) task. Site selection, proper debris classification, and survey schedule often 

prompt questions from new volunteers. A frequently asked questions document is provided in 

Section 7.7. 

As mentioned above, care should be given to avoid threatened or endangered species and 

habitats during site selection and while conducting surveys. While removal of debris from the 

environment is an important endeavor, it is not a long-term solution. The distinction between 

standing-stock and accumulation surveys, and the information gleaned from each, is important. 

Leaving debris on the shoreline allows surveyors to assess the variation in debris loads over time, 

which is essential information for quantifying the impacts of debris on the marine environment 

and making the case for increased prevention and mitigation efforts. 
19 

3.0 SURFACE WATER METHODS 

Floating marine debris has been noted by research and other vessels since 1971 (Carpenter et al., 

1972; Carpenter and Smith, 1972). However, few systematic quantification surveys have been 

conducted throughout the oceans to develop a cohesive understanding of the extent and degree of 

pollution from floating marine debris. 

Reported debris concentrations range from less than 1 piece/km2

 to 20,328 ± 2324 pieces/km2 in 

the subtropical Atlantic Ocean (Law et al., 2010), to potentially higher concentrations in the 

North Pacific Ocean (NRC 2008; see Section 7.1). In addition to a lack of standard sampling 

methodologies, metrics vary by study objective which complicates debris concentration 

comparisons. Weight and number of items are used to measure debris items, while area and 

volume measure the matrix sampled (Section 7.1). 

This section provides rigorous, standardized methodologies for assessing the amount and type of 

floating anthropogenic debris and guidance for the development of a robust survey design for 

coastal and offshore waters. Guidelines were developed to be flexible enough to conduct both 

coastal and offshore assessments. A goal for these guidelines is to increase the amount of surface 

water marine debris data that can be leveraged from tangentially-related organizations and 

projects that routinely conduct surface trawling. Data collected can facilitate comparisons to 

assess where floating debris is most prevalent and contribute to assessments of the eventual fate 

and risk posed by the debris. 

3.1 Floating debris survey techniques 

Floating marine debris and debris suspended in surface waters has been documented across the 

world in the open ocean and in coastal waters. In general, efforts to monitor oceanic marine 

debris have been informal, with many anecdotal reports, few scientific expeditions that included 

floating debris sighting surveys, and even fewer scientific expeditions dedicated to collection and 

quantification of floating marine debris samples. Early marine debris sampling was often 

conducted with pelagic plankton sampling. Methods have varied over the years to include 

oblique plankton tows (Carpenter et al., 1972) and Neuston nets towed across surface waters 

(Colton et al., 1974, Yamashita and Tanimura, 2007). In the North Atlantic Ocean, the Sea 

Education Association used Neuston nets towed by a sailing vessel in a standard procedure to 

produce a 22-year data set (Law et al., 2010). Moore et al. (2001b, 2002) published some of the 

first reports that demonstrate the use of a manta net in conducting debris trawls. Brown and 

Cheng (1981) note an advantage of the manta net is the two paravanes that attach to the frame 

and allow the net mouth to skim the surface of the water. Thompson et al. (2004) determined 

plastic fragment concentrations in archived samples collected with a continuous plankton 

recorder. 

Variability in the physical construction of nets, towing conditions, and overall technique make it 

difficult to interpret temporal and spatial trends of floating debris concentrations. These studies 

demonstrate a large variability in the physical construction of nets used in surface water debris 
20 

surveys, in terms of aperture, mesh size, and net length. Towing conditions, such as tow speed 

and trawl length, vary depending on the overall study objective (Section 7.1). Reported mesh 

sizes have ranged from 150 to 947 μm (NRC 2008) and though studies have not yet targeted 

floating nano-sized debris particles, it is possible that these could be sampled with various 

whole-water sampling techniques. Marine debris was investigated in new and archived surface 

water plankton tow samples from the CalCOFI program (Gilfillan et al. 2009, Doyle et al. 2011), 

which uses a manta net equipped with a flowmeter and 0.505 mm mesh for 15 minutes at a speed 

of approximately 1.0-1.5 knots. These methods have been employed in standard plankton tows 

for decades, and proved effective for sampling debris in surface waters. 

We evaluated the methodology from published literature to develop the guidelines presented in 

this document, which are heavily influenced by the California Cooperative Ocean and Fisheries 

Investigations (CalCOFI). The surface water debris sampling technique and study design 

described in this section were tested in a pilot sampling effort conducted in the Chesapeake Bay, 

as well as in a more rigorous testing of nearshore coastal waters in the Delmarva Peninsula 

(Versar, Inc. 2012). 

3.2 Survey Design 

Few studies have repeatedly sampled an area for marine debris using a standardized technique; 

often measurements are tangential to primary study objectives and debris data are not published. 

Even when long-term data exist, the patchiness of debris distribution may obscure expected 

trends (Law et al., 2010). 

To test the utility of the surface water guidelines described here, Versar, Inc. developed a nested 

survey design (Versar, Inc. 2012; see Section 7.3). As discussed in Section 2.4, at the coarsest 

level, two regions in the coastal mid-Atlantic United States were selected based on land use 

(urban vs. rural). Within each region, three 1000-m locations (stretches of shoreline) were 

identified. Adjacent to each location, nine surface water sampling stations were selected and 

remained fixed for the duration of the study. To avoid tow direction bias, direction of the tow 

was randomly assigned for each trawl. Surveys were conducted on a bi-weekly basis for a period 

of six months in accordance with the sampling technique described below. Results of the study 

indicate that floating macro-debris abundances in urban and rural locations did not differ 

significantly, but differences among locations and temporal trends were detected using this 

survey design. 

Given the widely variable debris concentrations noted by published reports and during testing by 

Versar, Inc., it is difficult to provide strict recommendations about survey design. Survey design 

should consider the following suggestions while tailoring the study to address specific questions 

about floating marine debris. 

3.2.1 Site Selection 

The coastal sampling design presented here pursues a regional perspective on floating debris and 

its relationship to shoreline debris. Additional considerations for offshore sampling include 
21 

oceanographic conditions; known currents, eddies, convergence patterns, mixing, and seasonal 

fluctuations therein; known or potential sources of marine debris; shipping lanes; and the 

bathymetry and geomorphic structures that may influence the generation and eventual fate of 

floating debris. Groups conducting offshore sampling are strongly encouraged to conduct 

surveys in conjunction with ongoing marine research and/or water quality assessments.

To provide a statistically robust dataset, selected sites for coastal surface water sampling should 

be stratified based on appropriate parameters, for example land use (e.g., urban, rural) associated 

with nearby shorelines, fishing activities, or storm water or sewage outfalls. Random site 

selection from each stratum (stratified random sampling) is a useful tool to assess temporal and 

spatial variability while controlling for some of the expected variability and reducing sampling 

error. In order to compare shoreline and adjacent surface water debris concentrations, shoreline 

site selection should occur before any surface water site selection takes place. 

Additionally, sites should have the following characteristics: 

 Direct, seasonal or year-round access, depending on location

 Located within one nautical mile from shore for comparison to shoreline debris loads

 No stationary or transient in-water barriers to ship transect path

 Preferably areas that have not seen recent changes or manmade alterations to 

hydrographic patterns

These characteristics should be met where possible, but should be analyzed on a case-by-case 

basis and modified if appropriate for a particular region/location. This technique may be adapted 

or modified to monitor riverine, coastal, and offshore locations. 

3.2.2 Sample Number and Frequency 

In addition to standardizing the technique and equipment used, it is equally important to 

complete enough sampling to account for heterogeneity in debris concentration (e.g., Pichel et 

al., 2007). Depending on study objectives, detecting significant trends or making regional 

comparisons may require an infeasible sample size (Ryan et al., 2009, Versar, Inc., 2012). It may 

be advantageous to conduct surveys initially more frequently to understand the spread of the data 

and factors affecting variability (MSFD, 2013). To increase confidence in debris concentration 

estimates, balance spatial distribution of sampling and the number of floating debris transects 

within a location with the amount of replication required at the shoreline site level (Versar, Inc., 

2012). 

Once location is determined, at least ten transects are identified, plotted in mapping software, 

and randomly numbered. Three numbers are selected from a random number table to determine 

which transects are evaluated on a sampling event. At least three transects should be completed 

within two nautical miles parallel to the adjacent shoreline site and within one nautical mile 

perpendicular to the shore (Figure 5). We suggest surveyors pair the surface water sampling 

frequency with adjacent shoreline assessments. And, where possible, groups are encouraged to 

conduct surveys in conjunction with ongoing marine research and/or water quality assessments. 
22 

Figure 5. Shoreline and pelagic sampling should be coordinated so that the pelagic trawl transects occur within two 

nautical miles of the shoreline assessment sites (here, denoted as a single 100 m section of beach). Three trawls, 

each approximately 0.5 nm, will be conducted at each site. Red circles represent points at which to note GPS 

coordinates. If obstructions are present, it is necessary to take GPS coordinates whenever the vessel changes heading 

and not only at the beginning and end of each trawl transect. 

3.3 Equipment 

The following equipment is suggested to perform surface trawls for floating marine debris: 

 Nautical charts

 Digital camera

 Hand-held GPS unit

 Extra batteries (suggest rechargeable batteries)

 Manta net 

 Detachable cod end (+ one spare)

 Bridle for manta net

 Weights to attach to frame, if in offshore or choppy waters

 Flowmeter

 Stopwatch
23 

 Squirt bottles

 Plastic buckets with handles (two 5-gallon)

 Stainless steel sieves (5-mm and 0.30-mm mesh)

 Calipers

 First aid kit (including sunscreen, bug spray, drinking water)

 Work gloves for hauling the net

 Latex gloves (or appropriate alternative) for handling the sample

 Stainless steel forceps, 6-inch, angled tip, for picking out larger debris items

 32-ounce (~1 L) amber glass sample bottles with lids

 Wide-mouth funnel (stainless steel) to fit glass bottles 

 Clipboards

 Data sheets (on waterproof paper)

 Waterproof labels for jars, pre-labeled and affixed to jars prior to trawls

 Pencils

 Permanent markers

 White trays, 12-inches square (or equivalent) for sorting debris

 Stainless steel spatula, ~8-inches in length, with tapered and rounded ends for sorting 

debris

 Sealant to repair net holes

 Bags for large debris items

 Instrument to measure water quality parameters (optional)

3.4 Pre-Survey Site Characterization 

Before completing floating debris surveys, shoreline characterization is completed for each 100 

m site. See Section 2.0 of this document for the methodology. 

For surveys of coastal waters adjacent to shoreline sites, current bathymetric maps should be 

obtained for the area within two nautical miles of the chosen shoreline site. Several potential 

sites for trawls are chosen based on ease of access and strata described in the survey design 

section. It is ideal to complete a survey of the surrounding surface waters before any sampling 

begins. For studies with concurrent shoreline surveys, any pertinent information on hydrography, 

bathymetry, and in-water barriers is also described in the “notes” section of the shoreline 

characterization data sheet. 

Select transects prior to arrival at the site. Each data sheet captures ancillary data and data 

pertaining to a single trawl event. Ancillary data may be recorded before arrival at the site. 

Each trawl transect has a unique identification in this suggested format: 

Site ID_year-month-day_transect # 

An example is [MD-MR_2010-01-07_T1] for a trawl completed in Maryland’s Middle River on 

January 7, 2010 along the first transect (identified as T1 in mapping software). 
24 

3.5 Surface Water Trawl Survey Methodology (> 0.30 mm) 

3.5.1 Trawling technique 

Figure 6. In-water setup for a manta tow. The vessel shown has an A-frame at the stern that is fully depressed, 

which supports a tow rope that is cleated to achieve and angle of ~20° between the vessel and the net to minimize 

interaction with the vessel’s wake. The shorter side of the bridle should be closer to the vessel to help facilitate 

avoidance of sampling the wake.

All transects follow the same trawling technique. A manta net, with a body composed of 0.330 

mm nylon mesh and measuring approximately 3 m in length, is towed horizontally at the surface 

(Figure 6). Depending on sea state, weights are added to the bridle to ensure balanced 

positioning and coverage of the surface waters. Alternately, weights may be added to a tow line 

that connects the bridle to the winch line. A swivel connects the tow rope to the manta net bridle, 

which is offset so that one side is slightly longer to encourage a towing angle that samples waters 

outside of the vessel’s wake. A buoy is attached to the net for safety and retrieval purposes. 

A digital or analog flowmeter is attached to the net frame and suspended in the center of the net 

mouth. An initial flowmeter reading is taken prior to deployment of the net apparatus; this 
25 

reading should not change before placement in the water. The net is deployed from the back or 

the side of the vessel, with enough slack to allow the net to smoothly skim the surface of the 

water and avoid the vessel’s wake. The side paravanes of the manta net should be on the water’s 

surface. An angle of approximately 20 degrees between the line of the vessel and the net is 

desirable for minimizing interaction with the vessel wake. The shorter side of the bridle should 

be closer to the vessel to obtain the required towing angle (Figure 6). 

The trawl is deployed for approximately 0.5 nautical miles at a speed of 1-3 knots, an 

approximately 15 minute duration. When noting the in-water time, include time for deployment 

and retraction when the net is submerged in the water and the flowmeter is recording volume. 

During the trawl, vessel speed and tow rope length may be adjusted to ensure the net is properly 

skimming the surface away from the vessel wake. One person watches the net and notes any 

large debris items that may be initially funneled into the net mouth. These should be detailed on 

a large debris data sheet. 

GPS coordinates are recorded in degree decimal format at the beginning and ending point of 

each trawl transect. This can be done with a handheld GPS unit or by marking coordinates of the 

vessel’s transect path in mapping software. If obstructions are present in the area and require 

alteration of the original transect, GPS coordinates should be recorded when the vessel changes 

heading (Figure 5). 

3.5.2 Sample Processing 

The flowmeter reading is recorded as soon as the net is recovered. Contents of the net are gently 

washed with natural seawater from the outside, into the cod end. If possible, ambient seawater is 

filtered through a 0.333 mm mesh sieve to remove particles that could bias the sample. The cod 

end is detached and its entire contents are rinsed with seawater. Digital photos document the 

process throughout, especially the cod end contents at the end of each trawl. 

Samples may be processed on the vessel or transferred to labeled sample jars for laboratory 

processing. Any obvious large debris items, >30 cm, are counted on a separate large debris data 

sheet, rinsed to collect any small attached particles, photographed, and then stored in bags or 

discarded appropriately. Large natural items can be discarded but should be rinsed to collect any 

small attached particles; items may be recorded on the data sheet and photographed depending 

on study objectives. 

When processing samples on the vessel, the remaining sample from the cod end is rinsed into 

stacked stainless steel sieves (5 mm and 0.333 mm) to separate debris items into two size 

fractions, (x > 5 mm) and (5 mm > x > 0.333 mm). Proper rinsing with squirt bottles filled with 

ambient seawater is essential to collect all natural and anthropogenic particles that may be 

attached to debris items and natural contents (e.g., floating leaves, woody stems, pine needles, 

jellyfish). Rinsing is important if samples will be analyzed for microplastic concentration; in that 

case, the study design may consider using deionized water for rinsing to decrease potential bias. 

Debris items larger than 5 mm are sorted by material category and tallied on debris data sheets. 

Macro-debris may then be discarded appropriately or archived depending on study objectives. 
26 

The size fraction smaller than 5 mm, composed of micro-debris, is carefully rinsed into glass 

sample bottles and stored frozen to prevent any sample degradation. 

If samples are not processed on the vessel, steps are taken to condense the sample by minimizing 

rinsing and cataloging any large debris items. Large items are processed as described above and 

removed from the sample. Trawl contents are rinsed into glass sample jars for sieving in the 

laboratory, following the sieving technique described above. Samples are processed as soon as 

possible to avoid the need for initial freezing or chemical preservation. 

Analytical methods are available for processing water, sediment, and sand samples to quantify 

microplastic debris (Baker et al., 2013). When applicable, archiving frozen samples for further 

analyses is suggested. 

3.6 Data analysis 

Volume of water filtered during each trawl is calculated based on the flowmeter used. In general, 

distance is calculated per trawl by subtracting the initial and final readings of the flowmeter and 

applying a correction factor specific to the flowmeter. Distance is then multiplied by the area of 

the net mouth to determine a volume of water filtered. The concentration (#items/m3

) of macrodebris items is calculated as follows: 

ൌ ܥ

݊

ܸ

C = concentration of debris items (# of debris items/m3) 

n = # of debris items observed 

V= volume of water filtered (m3) = [(net mouth width) × (net mouth height) × d ] 

d = distance traveled = (flowmeter final – flowmeter initial) × correction factor 

For a given sampling event: 

1. Calculate debris concentrations for each individual transect surveyed (a minimum of 

three per survey) using the equation above 

2. Take the mean of the three concentrations to calculate an overall site concentration (with 

a standard deviation) for that date 

3.7 Quality Control 

Quality control procedures increase the efficiency, accuracy, and precision of floating debris 

assessments. Safety and data management plans should be in place before sampling begins. For 

accuracy in positioning of trawl transects, develop a survey design before sampling begins and 

use a GIS to label all potential transects. Naming conventions should be standardized for 

notation on sample labels and data sheets. 
27 

Consistently following a standardized procedure is essential. Trawling and processing techniques 

should be monitored for consistency. During trawling, watch the manta net to ensure that it is 

properly skimming the water’s surface without creating excessive splashing of water in the net 

mouth that influences water sampling. If the manta net is not skimming properly, vessel speed 

(or other parameters) should be tweaked to provide appropriate positioning and water flow 

through the net. Debris counts should be confirmed by two individuals if possible; at least 20% 

samples should be analyzed separately by two people for quality assurance. Debris samples 

should be saved for additional testing if material type is not determined. For studies investigating 

micro-debris, rinsing standards are important and the suggestions listed here may be appended 

with additional controls such as using deionized or filtered water for rinsing, and conducting all 

rinsing within a controlled laboratory environment. Sieves and equipment should be thoroughly 

rinsed between trawl events. All instruments should be calibrated and cleaned regularly. 

Equipment and rigging should be cleaned and inspected after each sampling event. 

3.8 Considerations 

Assessing floating debris quantity and composition presents challenges and confounding factors. 

The recommended technique for floating debris surveys is meant to be robust to slight 

modifications depending on study objectives, and this has been noted in the text. This section 

presents additional considerations for employing the floating debris survey technique. 

3.8.1 Survey design 

As discussed in Section 1.2, debris sources and points of input are often impossible to determine. 

Several categories have been identified, including (1) larger pieces from land-based runoff or 

actual release; (2) larger pieces from ocean-based dumping or accidental release; (3) smaller 

pieces that result from the degradation of larger marine debris in the environment; and (4) small 

debris, for example, micro- and nano-plastics used in consumer products (e.g., plastic beads used 

as an exfoliant in soaps) that enter the waste stream from regular use and are likely discharged 

with wastewater (Fendall and Sewell 2009). Programs that seek to understand the source of 

debris should heavily consider survey design in terms of both selecting appropriate sites to 

monitor and adding enough replication to constrain the variability in debris concentrations 

attributed to environmental conditions. 

Local weather, runoff, other potential point sources of debris, and oceanographic conditions will 

be important to consider in the study design. Where possible, groups are encouraged to conduct 

surveys in conjunction with ongoing marine research and/or water quality assessments. This may 

necessitate adjustment to the suggested study design, but more important is standardizing the 

techniques used to collect and process the floating debris samples, as well as the metrics used to 

report debris concentrations. 

3.8.2 Technique 
28 

Note that, as a general rule, faster tow speeds and larger mesh sizes will exclude smaller particles 

and will bias the sample toward larger particles. The techniques recommended here provide an 

overview of the amount and type of debris present in surface waters at a given location, but due 

to operational constraints will not sample the entire water column or obtain all debris. Particles 

smaller than 0.33 mm (the suggested mesh size) will escape during trawling. Trawl transect 

lengths may be optimized based on local conditions. For example, during a phytoplankton bloom 

the mesh may become clogged and will not filter effectively. Techniques that diverge from the 

standard transect length or standard tow speed are especially encouraged to measure flow 

volume per trawl, in order to account for varying flow volumes in calculated concentrations. 

Depending on study objectives, samples may be processed in a clean laboratory environment 

with slight changes to sieving technique such as a more thorough washing with deionized water, 

a more detailed sorting based on additional size classes (e.g., additional sieving through a 1-mm 

screen), drying the total sample, and weighing debris items. All visible debris items may be 

measured with calipers. 

If study objectives involve correlating debris loads and water quality, parameters such as 

dissolved oxygen, pH, temperature, etc. should be recorded at the beginning and end of each 

transect. 

3.8.3 Data analysis 

The reporting unit is extremely important when making comparison to other comparable studies. 

For macro-debris, count (debris pieces) per volume (water filtered) provides an accurate 

measurement. This is a departure from most historic and present-day conventions, but is 

commonly used in marine plankton studies, is fairly simple to obtain, and allows for comparison 

of macro-debris concentrations in other matrices such as sand and sediments. Volumetric 

measures of surface water debris are useful because debris, especially plastic debris, can be 

neutrally buoyant and exist at depth in the water column due to wind-driven mixing (Kukulka et 

al., 2012). In the future, it may be possible to use measurements of floating marine debris to 

integrate a measurement through the water column; and thus providing an estimate for the 

amount of water filtered in each trawl would enhance parameterization. 

In some cases it may be useful to obtain mass measurements to estimate debris density within a 

given parcel of water (g/m3

). This measurement is informative for macro-debris, but is especially 

important for micro-debris particles that may not be easily counted. In addition, density estimates 

of micro-debris may be compared to density estimates of natural material in a given size class 

which provides an easily understood ratio of debris to the naturally occurring particles. Density 

is easily compared to whole water samples, benthic sediment grabs, and plankton abundance 

measurements that may be obtained in the same study. For very small particles (<1 mm), mass 

measurements will likely be more accurate than count. 

3.8.4 Relevance 
29 

Given the high variability in floating debris concentration, it may not be cost-effective to conduct 

enough sampling to accurately compare locations or regions, or to understand which 

environmental variables most influence debris concentration (Versar, Inc., 2012). To address this 

reality and strive for relevance with these techniques, this document stresses the benefits of 

completing floating marine debris surveys in conjunction with ongoing marine research and/or 

water quality surveys for increased efficiency in data collection. In addition, these techniques 

sample both macro- and micro-debris. Particles smaller than 5 mm have been documented in 

many water samples that did not contain macro-debris. Understanding the factors that affect the 

size distribution and particle concentration of debris in the ocean is important to advance the 

state of the science regarding debris movement, distribution, and degradation. These floating 

debris assessment techniques may be applied to address additional research questions beyond 

those posed at the beginning of this section. 
30 

4.0 AT-SEA VISUAL SURVEY METHODS 

4.1 Background 

Ship-based visual surveys are a relatively easy, cost-effective method for crowd-sourcing open 

ocean marine debris sightings (i.e., from vessels of opportunity) and can provide useful 

information on the types of debris commonly encountered and spatial and temporal variability of 

floating debris. The accuracy of reports generated from ship-based debris sightings is affected by 

environmental factors (e.g., weather conditions, sea state) and variation between observers (Ryan 

et al., 2009) and vessel size and speed (Rees and Pond, 1995). On larger vessels, observers are 

typically situated higher above the water surface and farther from the bow (e.g., on the bridge), 

which causes items very close to the bow to go undetected (Thiel et al., 2011). To account for the 

likelihood of surveyors missing some debris items located on a transect (Ryan 2013) apply a 

correction factor to measured debris counts based on item size and distance. Line transect 

sampling methods (where the perpendicular distance to each item is recorded) may reduce bias 

(Burnham and Anderson, 1984), but is not recommended for novice observers. It is important to 

recognize that although the majority of debris floating on the ocean surface is from the smaller 

size fractions (e.g., Law et al., 2010, Doyle et al. 2011, van Cauwenberghe et al., 2013), visual 

sightings will be skewed toward larger debris items. Further, unlike surface water trawls which 

will capture debris just beneath the surface (i.e., debris that has been subjected to wind mixing), 

visual surveys will only account for debris that is visible at the surface. Visual survey data 

should be interpreted as a low-end estimate of the total concentration of floating debris. 

A number of confounding factors must be taken into consideration for accurate comparisons of 

floating debris concentrations across time and space. Similar to marine debris in other 

environmental compartments, there is a lot of variability and patchiness in the abundance of 

floating debris. Large-scale convergence zones (e.g., the North Pacific High Pressure Zone), as 

well as small and meso-scale circulation features, may concentrate floating debris and create 

ephemeral debris patches. Areas of concentrated debris (which often also include natural debris) 

can be difficult to quantify from a moving vessel. One data analysis technique is to pool 

sightings from very long transects to account for debris patches (e.g., Ryan 2013 used 50 km 

transect lengths). 

Quantitative comparisons of different visual survey efforts noted in the literature are difficult to 

make due to the differences in reporting units (e.g., #items/km or #items/km2

), minimum debris 

size (studies have varied from 1.5 – 10 cm (Section 7.1)), and transect width (up to 100 m; e.g., 

Morris, 1980, Shiomoto and Kameda, 2005). Relative to debris classification systems used for 

other types of marine debris monitoring, a simplified data sheet should be used for visual surveys 

as it is difficult to collect detailed and accurate information on debris types from a ship-based 

observer. Thus, the visual survey data sheet provided in Section 7.5 does not cover the same 

level of detail as data sheets for shoreline sampling and surface water trawls. Given the 

uncertainty in detection and patchiness of large debris items, data collected through visual 

surveys may be most useful for qualitative assessments of the types and relative abundances of 

floating debris. 
31 

4.2 Survey Design 

Cheshire et al. (2009) provides methods for setting up a prescribed visual survey pattern in a 

given area and also for transect sampling. Given the widely variable debris concentrations noted 

by published reports, it is difficult to provide strict recommendations about survey design. 

Survey design should consider the suggestions put forth in the surface water trawl technique 

(Section 3.2), while tailoring the study to address specific questions about floating marine debris. 

Visual surveys may complement surface water trawl surveys and shoreline surveys. A survey 

design that includes visual surveys of floating debris conducted in conjunction with other survey 

types will lead to a more robust data set. Where possible, groups are encouraged to conduct 

surveys in conjunction with ongoing marine research and/or water quality assessments. This may 

include vessels of opportunity as well as structured studies that monitor at standard intervals. 

When vessels of opportunity are used as the platform for visual debris surveys, a structured study 

design is unlikely. This must be stated when data and results are reported (Ribic et al., 1992).

4.3 Equipment 

The following equipment is suggested to perform visual surveys of floating marine debris: 

 Clipboard 

 Pencil 

 Survey forms printed on waterproof paper 

 GPS unit 

 Binoculars 

 Digital camera 

4.4 At-Sea Visual Survey Technique 

Visual surveys should be conducted along strip transects at least 0.5 nm in length. Ancillary data, 

including environmental conditions and GPS locations of transect beginning and end points 

should be recorded on the visual survey form (Section 7.5). Any changes in heading during 

individual transects should be recorded in the space provided. If possible, two surveyors should 

conduct surveys from the bow of the vessel, and data from the port and starboard sides can be 

pooled from two separate data sheets. If only one surveyor is available, the surveyor may want to 

conduct the survey from the glare-free side of the vessel (Ribic et al., 1992). Each surveyor is 

responsible for visually scanning the sea surface and recording all debris > 2.5 cm that passes 

either the port or starboard side of the vessel (Figure 7). MSFD (2013) recommends that visual 

surveys not be conducted when environmental conditions are such that this minimum debris size 

cannot be detected, and provides suggested transect widths (ranging from 3 to 15 meters) based 

on vessel speed and height of the observer above the water (reproduced in Table 2). It is 

important to note that these suggested transect widths need to undergo further testing, and should 

be used only as a starting point. Binoculars may be used to verify the identity of items. 
32 

Observer height 

above water 

Ship Speed 

2 knots 6 knots 10 knots 

1 m 6 m 4 m 3 m 

3 m 8 m 6 m 4 m 

6 m 10 m 8 m 6 m 

10 m 15 m 10 m 5 m 

Table 2. Suggested visual survey transect widths based on observer height above water and ship speed. Adapted 

from MSFD (2013). Note that these suggestions are preliminary and will be further reviewed by the MSFD. 

Figure 7. During visual surveys, observers are responsible for visually scanning the sea surface on either the port or 

starboard side of the vessel, within a defined transect width. 

Visual survey data should be reported in terms of # items/km2, based on the transect width and 

length (determined from latitude and longitude of transect start and end points). To get an 

understanding of variability in detection from different observers, quality control surveys should 

be conducted on 20% of survey transects, by a second visual observer on the same side of the 
33 

vessel. Quality control surveys should be distributed among different sampling events and 

include consideration of debris classification and total count. 

4.5 Considerations 

As discussed above, ship-based debris observations can provide useful information on the 

abundances and types of debris floating at the sea surface. However, given the patchiness of 

surface water debris and uncertainty in debris classification during visual surveys, researchers 

must give careful consideration to survey design and standardization between observers and 

platforms in order to develop robust estimates of floating debris concentrations. 
34 

5.0 BENTHIC METHODS 

The information provided in this section is intended to guide development of benthic surveys to 

ensure that data and results can be integrated with surveys in other environmental compartments. 

Integration and standardization of survey efforts between shorelines, surface waters, and the 

benthos is important to understand and model the life cycle and behavior of debris. We suggest 

that groups interested in developing a benthic survey program follow the guidelines below and 

refer to more detailed protocols provided by the MSFD (MSFD, 2013). 

5.1 Background 

Historical methods for detection and survey of benthic debris vary according to vessel 

capabilities and available equipment, target debris type and size, location, personnel (e.g., 

availability, skill level, training, technical abilities), and environmental conditions (e.g., depth, 

water clarity, current strength). Benthic monitoring efforts are often cost-prohibitive and more 

logistically challenging than some other types of marine debris monitoring (namely, shoreline 

monitoring), and there is often a lot of spatial variability in benthic debris concentrations. 

However, the seafloor is recognized as a potentially significant debris sink that should not be 

ignored. 

MSFD (2013) provides suggested methods based on depth, divided between shallow (< 20 m; 

SCUBA), shelf (up to 800 m; trawls), and deep sea floor environments; the sections that follow 

provide a general overview of the MSFD (2013) suggested approach. It is recognized that there 

is no single technique that will work across survey efforts in diverse environments and with 

different objectives and available resources. The guidelines presented here should be used as a 

guiding framework during the planning process, during which operation-specific protocols and 

safety measures will be developed. 

Benthic debris items should be catalogued according to the same classification system used for 

other environmental compartments. That is, debris should be tallied according to the material 

types and item categories captured on shoreline and surface water data sheets (Section 7.5). 

Further, to ensure comparability with data collected on shorelines and in surface waters, the 

focus should be on debris abundance (count and concentration) rather than weight. However, 

from a management perspective it might be informative and efficient to concurrently collect 

volume, size, and/or weight estimates. In instances where debris is not collected during surveys, 

there will be a lower degree of confidence in accurate item classification (e.g., diver or 

submersible surveys). A list of the benthic marine debris survey literature reviewed is provided 

in Section 7.1. Side scan sonar is not considered here given that it is only feasible for detection of 

large debris items, for example derelict crab pots (Stevens et al., 2000; Morison and Murphy, 

2009). 

Although assessment of micro-debris (< 5 mm) is not a focus of this document, it is worth noting 

that concurrent sampling of this small size fraction during macro-debris assessment requires the 

use of sediment grabs or trawls with a fine mesh size (e.g., Cole et al., 2011). 
35 

5.2 Survey Design 

5.2.1 Site Selection 

Survey locations are dependent on accessibility, study objectives, and available resources and 

equipment. Sensitive habitats or species and underwater hazards should be avoided. This 

includes sites that may contain unexploded ordinance or have features that may pose an 

entanglement hazard to divers or gear. Given the patchiness of benthic debris, sampling should 

focus on areas where debris is suspected to accumulate and may be stratified by factors such as 

land use, proximity to river mouths, substrate, tourism, fishing pressure, or oceanic current 

patterns. Bathymetry and hydrodynamics should be considered during site selection as there is 

growing evidence of their influence on benthic debris accumulations (e.g., Galgani et al. 1996; 

Keller et al. 2010). Acha et al. (2003) show that salinity fronts associated with river mouths tend 

to trap debris and may be common accumulation areas. 

5.2.2 Sample Frequency 

Survey frequency for benthic debris assessments should be determined based on study 

objectives, available resources, and expected seasonal or annual variability. In the Bay of Biscay 

(France), Galgani et al (1995a) found a greater abundance and more spatial variability in benthic 

debris trawls during the winter / early spring compared to other times of the year when debris 

concentrations were more uniform. The authors suggest that this variation may be due to 

seasonal changes in coastal currents and water levels. Quarterly or biannual sampling may be 

appropriate in regions that exhibit less seasonality (e.g., tropical regions with wet / dry seasons) 

and sampling may be further restricted by weather conditions and accessibility in high latitude 

areas. 

5.3 Shallow Environments (< 20 m) 

Based on proximity to source, shallow nearshore regions are more likely to accumulate seafloor 

debris. In areas where there are strong bottom currents or intense storm activity, debris may be 

pushed farther out on the continental shelf, accumulate around rocky ledges or outcrops, or be 

deposited in offshore canyons or other depressions (e.g., Galgani et al., 1996, Bauer et al., 2008, 

Kendall et al., 2007, Wei et al., 2012, Schlining et al., 2013). 

Dive surveys along line or strip transects are often the preferred method for assessment of 

seafloor debris in shallow or coastal environments. The ability to detect debris is a significant 

concern during underwater visual surveys, and the dimensions of each sampling unit (e.g., 

transect length and width) should be based on estimated debris concentration, detectability, and 

environmental conditions. Diver experience may also affect the degree of detection (Ribic et al., 

1992). MSFD (2013) provides a range of transect lengths (20 – 200 m) and widths (4 – 8 m) 

based on environmental conditions and debris concentration (based on Katsanevakis, 2009; see 
36 

Table 3). In order to double the areal coverage of surveys, the UNEP survey technique employs a 

pair of divers, one on each side of the transect line (Cheshire et al., 2009). Further, MSFD 

recommends the use of a distance sampling method, where divers record the distance of each 

debris item from the line so that a degree of detectability can be applied during debris 

concentration calculations. A minimum debris size must be identified prior to any survey 

activities. The minimum debris size should be based on study objectives but should not be 

smaller than the lower limit of detection (Donohue et al., 2001, Timmers and Kistner, 2005); 

ideally all items > 2.5 cm are detectable. Selecting a smaller minimum debris size cut-off will 

require more time and resources. Results of dive transect surveys are expressed in terms of 

#items/m2

. 

Debris 

Density 

Environmental 

Conditions 

Sampling Unit 

(length x width) 

0.1 – 1 items / m2 Low turbidity & high habitat complexity 20 m x 4 m 

0.1 – 1 items / m2 High turbidity 20 m x 4 m 

0.01 – 0.1 items / m2 In every case 100 m x 8 m 

< 0.01 items / m2 In every case 200 m x 8 m 

Table 3. Suggested dive survey transect lengths and widths based on environmental conditions and debris 

concentration. Adapted from MSFD (2013) and Katsanevakis (2009). 

To ensure that all of the appropriately sized debris items within a transect are recorded, quality 

control estimates should be conducted by a second surveyor on 20% of the total number of 

transects sampled per site over the course of the study. Quality assurance sampling should be 

distributed among different sampling events and include consideration of debris classification. 

Both SCUBA and snorkel free-dive techniques have been used for shallow water benthic debris 

assessments (e.g., Donohue et al., 2001, Bauer et al., 2008; see Section 7.1). Existing biological 

monitoring programs that employ diver surveys may provide an opportunity for collaboration. 

Debris surveys would be more economical and efficient if combined with existing benthic 

ecology or other monitoring efforts. 

For any diving activities or other use of compressed gas as a breathing medium (e.g., surface 

supplied air), safety is the number one priority and divers must be trained to a level 

commensurate with the type and conditions of the diving activity being undertaken. Project leads 

are responsible for understanding all aspects of dive safety regulations and required trainings 

(e.g., OSHA distinctions between scientific and commercial diving) and must ensure that their 

organization has the capacity to oversee all planned diving activities (e.g., appropriate insurance, 

safety policies, etc.). 

 

5.4 Continental Shelves (up to 800 m) 

In locations where it is too deep for dive surveys, debris assessments can be combined with 

ongoing trawl surveys, for example benthic ecology studies or fish stock assessments (e.g., 

Keller et al., 2010). Although debris loads are likely underestimated with trawls, not all debris is 
37 

captured and debris may be lost while the net is returned to the vessel; (Spengler and Costa, 

2008), trawl surveys can provide an idea of the relative types and abundances of benthic marine 

debris, which is informative at a local or regional level. It should be noted that trawling activities 

are largely limited to smooth and flat areas of the seafloor, which are not indicative of typical 

debris accumulation areas (Galgani et al., 1995a). Ribic et al. (1992) point out that variability in 

the vessel, crew, net type (including footrope), depth sampled, and weather will affect the 

accuracy of measurements. 

UNEP (Cheshire et al., 2009) provides a benthic trawl survey design. The suggested approach is 

to select a 5 km by 5 km survey area, create a grid of 25 km2

, randomly select three sub-blocks 

of 1 km2, and conduct five parallel trawls of 800 m each within each selected sub-block. Trawls 

should be separated by at least 200 m and data from all transects should be aggregated to report 

an overall debris concentration. Trawl equipment should have a fixed mouth width (e.g., otter 

trawls) such that debris concentrations can be reported in units of #items/km2

 based on the 

distance trawled. 

To ensure that all of the appropriately sized debris items within a sample are recorded, quality 

control assessments should be conducted by a second individual on 20% of the total number of 

samples per site over the course of the study. Quality assurance sampling should be distributed 

among different sampling events and include consideration of debris classification. 

It is important to consider the impacts of any trawling activity on benthic ecosystems, and 

sensitive or protected habitats and species should be avoided. Marine debris trawl surveys are 

more affordable and less destructive if combined with existing sampling programs. Van 

Cauwenberghe et al. (2013) applied the UNEP trawl survey design on the Belgian continental 

shelf and argue that the trawls were an inefficient use of time and resources. 

5.5 Deep Sea Floor 

There is a paucity of data available on debris in the deep sea, particularly in areas where trawling 

is not a viable option. Debris is expected to accumulate in relatively calm areas with high 

sedimentation rates, and studies have shown that debris tends to accumulate near outcrops and in 

offshore canyons or channels (e.g., Galgani et al., 1996, Kendall et al. 2007, Wei et al., 2012, 

Schlining et al. 2013). In regions of the seafloor with varying topography (e.g., outcrops, 

canyons, steep slopes), submersibles are the only viable option for marine debris surveys. 

Remotely operated vehicles (ROVs) and manned submersibles have previously been used for 

debris surveys (Section 7.1), but are restrictively expensive in many cases. Detectability is a 

significant concern for surveys that employ submersibles, and in some cases the vehicle may 

purposely avoid debris due to entanglement hazards. Further, the color, size, shape, fouling, and 

degree of burial in sediments will affect detectability (Ribic et al., 1992). In Monterey Bay, CA a 

22-year archive of ROV video footage was recently analyzed for marine debris sightings 

(Schlining et al., 2013). The study added to our understanding of typical accumulation regions 

but no estimation of debris concentration was provided. 
38 

5.6 Considerations 

Benthic debris has been shown to inflict negative impacts on marine species and habitats, 

particularly corals (e.g., Schleyer and Tomalin, 2000, Bauer et al., 2008, Yoshikawa and Asoh, 

2004). Thus, it may be worthwhile to identify relationships between bottom communities and 

marine debris in various environments (Bauer et al., 2008). Benthic debris typically has a very 

patchy distribution, so surveys may be a necessary first step to prioritize debris cleanup efforts, 

but considerable effort is required in order to cover large regions of the seafloor (Galgani et al., 

1996). As mentioned above, although the benthos is likely a significant sink for marine debris, 

surveys are often prohibitively expensive and logistically complicated compared to other types of 

monitoring. 

When designing a study, it is important consider and report the lower size limit for detection, 

which will be based on the equipment used, habitat type, and in some cases water clarity. In 

addition, information on the depth range over which sampling occurs and total area of seafloor 

sampled is important (Spengler and Costa, 2008). Regardless of the benthic survey technique 

employed, #items/unit area is the suggested basic reporting unit. 
39 

6.0 REFERENCES 

This section contains references cited within the main text of this document and in literature 

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42 

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44 

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45 

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47 

7.0 APPENDICES 
48 

7.1 Literature Review Tables2

Shoreline survey literature reviewed: 

Citation Location General Metrics

Alkalay et al. 2006 Israel Debris count, concentration 

Cauwenberghe et al 2013 Belgian shelf and shoreline Debris concentration, weight 

Edyvane et al. 2004 Anxious Bay, Australia 

Debris count, weight, source, 

and entanglement 

Eriksson et al 2012 

Two islands south of 

Australia Debris concentration/day

Frost & Cullen 1997 

New South Wales, 

Australia 

Debris concentration, weight, 

source 

Jambeck et al., 2009 New Hampshire, USA 

Debris count, source, 

entanglement 

Kusui & Noda 2003 

Sea of Japan 

(Japan & Russia) Debris count, weight, and source 

Liu et al. 2013 Taiwan - southwest coast Debris concentration 

Moore et al., 2001a Orange County, California 

Debris concentration, weight, 

source 

Morishige et al. 2007 Northwest Hawaiian Islands Climate/weather, Debris count 

Oigman-Pszcsol & Creed 

2007 SE Brazil Debris count, concentration 

Rees & Pond 1995 United Kingdom Debris count, source 

Ribic et al 2010 Nationwide USA 

Debris count, source, 

entanglement 

Ribic et al 2011 

Caribbean and Gulf of 

Mexico 

Debris count, source, 

entanglement 

Ribic et al. 1994 Nationwide Debris count, source 

Rosevelt et al 2013 Monterey Bay, California Debris concentration 

Sheavly 2007 Nationwide USA 

Debris count, source, 

entanglement 

Thiel et al., 2013 North-central Chile Debris concentration 

Visual survey literature reviewed: 

Citation Location

Transect width 

(distance from 

ship) Metric

Day et al 1990 North Pacific 50 m items / km2

Matsumura and 

Nasu, 1997 Japan no limit items / km2

Ryan, 2013 

Bay of Bengal / Straits of 

Malacca (Indian Ocean) 50 m items / km2

Shiomoto and 

Kameda, 2005 nearshore Japan 100 m items / km2

Thiel et al 2003 SE Pacific (near Chile) 10 m items / km2

Thiel et al 2011 German Bight, North Sea 20 - 70 m items / km2

2

 These publications were reviewed during development of NOAA survey techniques, and do not necessarily 

represent an exhaustive literature review. 
49 

Surface water trawl literature reviewed: 

Citation Location Depth Range Method Metrics

Carpenter et al., 

1972 

coastal North 

Atlantic Ocean 

surface to 

unspecified 

depth 

oblique plankton net using 

0.33-mesh 

#/m3

Carpenter and 

Smith, 1972 

Sargasso Sea surface neuston net tows using 

0.33-mm mesh at 2 knots 

#/km2 and g/km2

Colton et al., 1974 North Atlantic Ocean 

Caribbean 

surface neuston net tows using 

0.947-mm mesh at 5 knots 

#/km2 and g/km2

Day et al., 1990 North Pacific Ocean, 

Bering Sea, Japan 

Sea 

surface ring net or Sameoto net 

tows with 0.50-mesh 

#/km2

 and g/km2

Day and Shaw, 1987 North Pacific Ocean paper? 

Doyle et al., 2011 Bering Sea; 

California Current 

surface (10-15 

cm) and 

subsurface 

(California) to 

212 m 

Sameoto neuston net tows 

using 0.505-mm mesh at 

1.5-2.0 knots; manta net 

using 0.505-mm mesh; 

subsurface cruises used 

Bongo nets with 0.505-mm 

mesh 

#/m3 and mg/m3

Gilfillan et al., 2009 California Current surface manta net tows using 0.505-

mm mesh at 0.5-0.75 m/s 

#/m3 and mg/m3

Goldstein et al., 

2012 

North Pacific Ocean surface ovoid and rectangular 

plankton net tows using 

0.505-mm mesh at 2 m/s; 

manta net tows using 0.333-

mm mesh at 0.7-1 m/s 

#/m3 and mg/m3

Lattin et al., 2004 California Current surface to 5m neuston net tows (manta) 

using 0.333-mm mesh; 

bongo net tows using 0.333-

mm mesh; both at 1.0-2.3 

m/s 

#/m3 and g/m3

Law et al., 2010 North Atlantic 

Subtropical Gyre 

surface neuston net tows using 

0.335-mm mesh at 2 knots 

#/km2

Moore et al., 

2001(b) 

North Pacific Ocean surface manta net tows using 0.33-

mesh at 1 m/s 

#/km2

Moore et al., 2002 coastal North Pacific 

Ocean; California 

Coastal Current 

surface manta net tows using 0.33-

mesh at 1 m/s 

#/m3 and g/m3

Moret-Ferguson et 

al., 2010 

North Atlantic Ocean surface neuston net tows using 

0.335-mm mesh at 2 knots 

average count 

(#), size (mm), 

mass (g), density 

(g/mL) 

Ogi et al., 1999 coastal Japan surface neuston net tows using 0.3-

1.8 mm mesh at 2 knots 

#/km2 and g 

Ryan et al., 2009 review comprehensive n/a n/a 

Thompson et al., 

2004 

North Sea; North 

Atlantic Ocean 

10m continuous plankton 

recorder using 127mm2

aperture onto 0.280-mm 

mesh 

#/m3

Yamashita and 

Tanimura, 2007 

North Pacific Ocean; 

Kuroshio Current 

surface manta net tows using 0.33-

mm mesh at 2 knots 

#/km2
50 

Benthic survey literature reviewed: 

Citation Location Depth Range Method Metrics

Donohue et al 2001 

Northwestern Hawaiian 

Islands > 10 m snorkel items / km2

Bauer et al 2008 

Grey's Reef, South Atlantic 

Bight, USA 16 - 20 m SCUBA # items / 100 m2

Chiappone et al 

2004 Florida Keys < 8 m SCUBA # items / 100 m2

Acha et al 2003 

Rio del la Plata, South 

America 6 - 23 m trawl items / km2

Cauwenberghe et al 

2013 Southern North Sea, Belgium not reported trawl items / km2

Galgani et al 1995a 

Seine Bay and Bay of Biscay, 

France 0 - 100 m trawl # items / hectare 

Galgani et al 1995b Northwestern Mediterranean up to 750 m trawl # items / hectare 

Galgani et al 1996* Gulf of Lions, France 100 - 1600 m trawl # items / hectare 

Galgani et al 2000* European Seas at least 2200 m trawl # items / hectare 

Hess et al 1990 Kodiak Island, AK not reported trawl items / km2

June 1990 Oregon and Bering Sea 7 - 675 m trawl items / km2

Keller et al 2010 US West Coast 55 - 1280 m trawl 

items / km2 and 

kg / km2

Lee et al 2006 

East China Sea and South Sea 

of Korea not reported trawl kg / km2

Stefatos et al 1999 Ionian Sea, Greece not reported trawl items / km2

Wei et al. 2012 Gulf of Mexico 359 - 3724 m trawl # items / hectare 

Galgani et al 1996* 

offshore Marseille and Nice, 

France 40 - 1448 m 

manned 

submersible # items / 100 m 

Galgani et al 2000* European Seas 50 - 2700 m 

manned 

submersible # items / km 

Watters et al 2010 

Monterey Bay and Southern 

California 20 - 365 m 

manned 

submersible # items / 100 m 

Schlining et al 2013 Monterey Bay, CA 25 - 3971 m ROV 

# items 

(normalized 

debris counts - 

relative 

abundance) 

* Studies listed twice because they employed more than one survey method.
51 

7.2 Shoreline Survey Advisory Group 

Nir Barnea (NOAA Marine Debris Division) 

Jenna Jambeck (University of Georgia) 

Shelly Moore (Southern California Coastal Waters Research Project) 

Carey Morishige (NOAA Marine Debris Division) 

Seba Sheavly (Sheavly Consultants) 

Shay Viehman (NOAA Center for Coastal Fisheries and Habitat Research) 

Katherine Weiler (Environmental Protection Agency) 
52 

7.3 Versar, Inc. Executive Summary 

The text below is the executive summary of the final report compiled by Versar, Inc. (Versar, 

Inc., 2012) based on comprehensive testing of the shoreline and surface water survey techniques 

presented in this document. The complete report can be accessed at 

www.clearinghouse.marinedebris.noaa.gov. 

Developing standardized protocols to quantify marine debris is critical for the protection of 

natural resources and for evaluating debris removal programs and policies designed to reduce 

marine debris. The National Oceanic and Atmospheric Administration (NOAA) Marine 

Debris Division (MDD) developed a suite of sampling protocols to quantify marine debris on 

coastal shoreline habitats and in nearshore pelagic surface waters. We developed a large scale 

pilot project to test the ability of the protocols to quantify marine debris, monitor changes in 

debris density, and assess factors correlated with changes in debris density on short and longterm timescales. The overall goal of the pilot project was to provide feedback to the MDD on 

the level of sampling effort required to implement the protocols in a larger assessment 

program. Two sampling regions representing urban and rural land use in the coastal zone of 

the mid-Atlantic Bight were chosen to conduct the pilot project. Within the urban and rural 

regions, three locations consisting of three sampling sites each were sampled for marine 

debris along the shoreline and in the ocean using visual shoreline transect surveys and pelagic 

net sampling methods designed by the MDD. Each region was sampled bi-weekly from June 

27th to December 08th, 2011 for a total of 12 sampling events per region over the 24 week 

survey. 

MDD sampling protocols were successfully employed to sample debris and make estimates 

of debris densities. Debris was more common in the shoreline compared to the pelagic 

portion of the survey for each size class of debris. Plastic was the most common form of 

debris observed. Shoreline macrodebris varied over time and at each level of spatial 

resolution except for the region level. The urban and rural region had similar debris densities. 

Differences among shoreline locations were best explained by the sampling event on which 

the location was sampled, the number of people per site, and the total debris density. 

Shoreline macrodebris was weakly correlated with densities of people and the week of 

sampling. Both debris density and the number of people decreased over the course of the 

survey. Relative standard errors for shoreline macrodebris at the region, location, and site 

levels indicate that reasonably precise estimates were made (RSE<=30% in most instances). 

Pelagic macrodebris varied among locations but was similar between regions, among 

transects, and over time. Pelagic macrodebris was positively correlated with surface water 

temperature. Differences among pelagic locations were best explained by the sampling event 

during which the location was sampled and the surface water temperature. Relative standard 

errors for pelagic macrodebris at each spatial resolution indicate that estimates are imprecise 

due to high spatial and temporal variability of debris in the water. Sample size analyses 

indicate that sample size would have to increase exorbitantly to distinguish urban from rural 

due to the high degree of similarity between regions. Overall we found the sampling 

protocols employed in this survey are consistent and repeatable and based on our assessment 

would have the flexibility to serve as a guide for standardized methods for quantifying 

marine debris in small or large scale marine debris monitoring and assessment surveys. To 

further enhance these sampling protocols and future surveys we recommend (1) that a critical 

evaluation be conducted to determine the value of comparing differences in marine debris 
53 

between land use types, (2) additional protocol testing be conducted in other shoreline habitat 

types, (3) readily available GIS and location specific data from U.S. regions be identified and 

compiled into a comprehensive GIS, and (4) that shoreline sampling continue in the location 

of the current pilot survey using a stratified random sampling rather than fixed sampling 

approach.
54 

7.4 Random Number Tables 

Transect Selection Random Number Table 

1 2 3 4 5 

1 4 8 17 9 1

2 7 19 2 12 20

3 18 14 6 16 11

4 3 5 15 10 13

Micro-Debris Random Number Table 

1 2 3 4 5 

1 6 2 14 17 19 

2 8 10 13 5 9 

3 16 18 15 4 7 

4 1 3 20 12 11 

5m 

Each column represents 1m of transect width. Rows represent zones of a 

shoreline section. 

white = above the wrack line (closer to the first barrier) 

light gray = at the wrack line 

dark gray = below the wrack line (closer to the water) 
55 

Transect ID # from start of 

100 m shoreline section 

1 0-5m 0-16'4"

2 5-10m 16'4"- 32'9"

3 10-15m 32'9" - 49'2"

4 15-20m 49'2" - 65'7"

5 20-25m 65'7" - 82'

6 25-30m 82' - 98'5"

7 30-35m 98'5" - 114'9"

8 35-40m 114'9" - 131'2"

9 40-45m 131'2" - 147'7"

10 45-50m 147'7" - 164'

11 50-55m 164' - 180'5"

12 55-60m 180'5" - 196'10"

13 60-65m 196'10" - 213'3"

14 65-70m 213'3" - 229'7"

15 70-75m 229'7" - 246'

16 75-80m 246' - 262'5"

17 80-85m 262'5" - 278'10"

18 85-90m 278'5" - 295'3"

19 90-95m 295'3" - 311'8"

20 95-100m 311'8" - 328'1"
56 

7.5 Data sheets 

7.5.1 Shoreline data sheets 

 
SHORELINE DEBRIS

Site Characterization Sheet

Standing‐Stock Surveys

Organization	 Name	of	organization	responsible	

for	collecting	the	data	

Surveyor	name	 Name	of	person	responsible	for	

filling	in	this	sheet	

Phone	number	 Phone	contact	for	surveyor	

Complete	this	form	ONCE	for	

each	site	location	 Date	 Date	of	this	survey	

SAMPLING AREA

Shoreline	name	

Name	or	ID	by	which	this	section	of	

shoreline	is	known	(e.g.,	beach	

name,	park)	

State/County	 State	and	county	where	your	site	is	

located	

Coordinates	at	start	of	

shoreline	section	

Latitude	 Longitude	

Recorded	as	XXX.XXXX	(decimal	

degrees)	at	start	of	shoreline	section	

(in	both	corners	if	width	>	6	meters)	

Coordinates	at	end	of	

shoreline	section	

Latitude	 Longitude	

Recorded	as	XXX.XXXX	(decimal	

degrees)	at	end	of	shoreline	section	

(in	both	corners	if	width	>	6	meters)	

Photo	number/ID	 The	digital	identification	number(s)	

of	photos	taken	of	shoreline	section	

SHORELINE CHARACTERISTICS

Length	of	sample	area	

(usually	100	m)	

Length	measured	along	the	

midpoint	of	the	shoreline	(in	

meters)	

Shoreline	slope	(o)	 Slope	above	horizontal	(between	0	–

90o)	

Substratum	type	 For	example,	a	sandy	or	gravel	

beach	

Substrate	uniformity	 Percent	coverage	of	the	primary

substrate	type	(%)		

Tidal	range	 Max	&	min	vertical	tidal	range.	Use	

tide	chart	(usually	in	feet).	

Tidal	distance	

Horizontal	distance	(in	meters)	from	

low‐	to	high‐tide	line.	Measure	on	

beach	at	low	and	high	tides	or	

estimate	based	on	wrack	lines.	

Back	of	shoreline	

Describe	landward	limit	(e.g.,	

vegetation,	rock	wall,	cliff,	dunes,	

parking	lot)	

Aspect	

Direction	you	are	facing	when	you	

look	out	at	the	water	(e.g.,	

northeast)	
LAND‐USE CHARACTERISTICS

Location	&	major	usage	

Urban	 Select	one	and	indicate	major	

usage	(e.g.,	recreation,	boat	

access,	remote)	

Suburban	

Rural	

Access	

Vehicular	(you	can	drive	to	your	

site),	pedestrian	(must	walk),	

isolated	(need	a	boat	or	plane)	

Nearest	town	 Name	of	nearest	town	

Nearest	town	distance	 Distance	to	nearest	town	(miles)	

Nearest	town	direction	 Direction	to	nearest	town	

(cardinal	direction)	

Nearest	river	name	

If	applicable,	name	of	nearest	

river	or	stream.	If	blank,	assumed	

to	mean	no	inputs	nearby	

Nearest	river	distance	 Distance	to	nearest	river/stream	

(km)	

Nearest	river	direction	 Direction	to	nearest	river/stream	

(cardinal	direction	from	site)	

River/creek	input	to	

beach	 YES	 NO	

Does	nearest	river/stream	have	

an	outlet	within	this	shoreline	

section?	

Pipe	or	drain	input	 YES	 NO	

Is	there	a	storm	drain	or	

channelized	outlet	within	

shoreline	section?	

Notes	(including	description,	landmarks,	coastal	hydrography,	offshore	barriers,	etc.):	
SHORELINE DEBRIS

Survey Data Sheet

Organization	 Name	of	organization	responsible	for	

data	collection	

Surveyor	name	 Name	of	person	responsible	for	filling	in	

this	sheet	

Phone	number	 Phone	contact	for	surveyor	

Complete	this	form	during	

EACH transect	

Email	address	 Email	contact	for	surveyor	

Date	 Date	of	this	survey	

ANCILLARY	INFORMATION

Shoreline	name	 Name	for	section	of	shoreline	(e.g.,	

beach	name,	park)	

Transect	#	and	photo	ID	 Transect	#	(1‐20)	and	digital	photo	

number	of	transect	

Coordinates	of	start	of	

shoreline	site	

Latitude	 Longitude	 Recorded	as	XXX.XXXX	(decimal	

degrees).	Record	in	both	corners	if	

width	>	6	m.	If	transect,	record	at	

water’s	edge.	

Coordinates	of	end	of	

shoreline	site	

Latitude	 Longitude	 Recorded	as	XXX.XXXX	(decimal	

degrees).	Record	in	both	corners	if	

width	>	6	m.	If	transect,	record	at	back	

of	shoreline.		

Width	of	beach	 Width	of	beach	at	time	of	survey	from	

water’s	edge	to	back	of	shoreline	

(meters)	

Time	start/end	 Start	 End	 Time	at	the	beginning	and	end	of	the	

survey	

Time	of	low	tide	 Time	of	the	most	recent	or	upcoming	

low	tide.	

Season	 Spring,	summer,	fall,	winter,	tropical	

wet,	etc.	

Date	of	last	survey	 Date	on	which	the	last	survey	was	

conducted	

Storm	activity	 Describe	significant	storm	activity	

within	the	previous	week	(date(s),	high	

winds,	etc.)	

Current	weather	 Describe	weather	on	sampling	day,	

including	wind	speed	and	%	cloud	

coverage	

Number	of	persons	 Number	of	persons	conducting	the	

survey	

Large	items	 YES	 NO	 Did	you	note	large	items	in	the	large	

debris	section?	

Debris	behind	back	

barrier?	

YES	 NO	 Is	there	debris	behind	the	back	barrier	

of	the	site	(if	yes,	do	not	include	it	in	

tallies	below)	

Photo	ID	#s	 The	digital	identification	number(s)	of	

debris	photos	taken	during	this	transect.	
Notes:	Evidence	of	cleanup,	sampling	issues,	etc.	

DEBRIS DATA: (continued on back)

ITEM	 TALLY	(e.g.,	IIII)	 TOTAL		

PLASTIC

Plastic	fragments	 Hard Foamed Film	

Food	wrappers	

Beverage	bottles	

Other	jugs	or	containers	

Bottle	or	container	caps	

Cigar	tips	

Cigarettes	

Disposable	cigarette	lighters	

6‐pack	rings	

Bags	

Plastic	rope/small	net	pieces	

Buoys	&	floats	

Fishing	lures	&	line	

Cups	(including	

polystyrene/foamed	plastic)	

Plastic	utensils	

Straws	

Balloons	

Personal	care	products	

Other:	

METAL

Aluminum/tin	cans	

Aerosol	cans	

Metal	fragments	

Other:	

GLASS

Beverage	bottles	

Jars	

Glass	fragments	

Other:	
ITEM	 TALLY	(e.g.,	IIII)	 TOTAL	

RUBBER

Flip‐flops	

Gloves	

Tires	

Rubber	fragments	

Other:	

PROCESSED LUMBER (no natural wood)

Cardboard	cartons	

Paper	and	cardboard	

Paper	bags	

Lumber/building	material	

Other:	

CLOTH/FABRIC

Clothing	&	shoes	

Gloves	(non‐rubber)	

Towels/rags	

Rope/net	pieces	(non‐nylon)	

Fabric	pieces	

Other:	

OTHER/UNCLASSIFIABLE

LARGE DEBRIS ITEMS (> 1 foot or ~ 0.3 m)

Item	type		

(vessel,	net,	etc.)

Status	(sunken,	

stranded,	buried)	

Approximate	

width	(m)	

Approximate	

length	(m)	

Description	/		

photo	ID	#	

Notes	on	debris	items,	description	of	“Other/unclassifiable”	items,	etc:	
7.5.2 Trawl data sheets 
Map: Space provided below for sketching a map of the site, including important

bathymetric or hydrographic features.

PELAGIC DEBRIS

Trawl Data Sheet

Organization	 Name	of	organization	responsible	for	data	

collection	

Surveyor	name	 Name	of	person	responsible	for	filling in	this	

sheet	

Phone	number	 Phone	contact	for	surveyor	

Complete	this	form	during	

each	trawl	

Email	address	 Email	contact	for	surveyor	

Date	 Date	of	this	survey	

ANCILLARY	INFORMATION	

Body	of	water,	location	 Name	of	the	water	body	and	the	approximate	

location	of	the	trawl	(sketch	map	below)	

Date	of	last	survey	 Date	on	which	the	last	survey	was	completed	

Current	weather	 Wind	 Cloud	cover	 Sea	state	 Describe	current	weather	including	wind	

speed,	%	cloud	cover,	sea	state	

Storm	activity	 Describe	significant	storm	activity	in	previous	

week	(e.g.,	date,	high	winds)	

Number	of	persons	 Number	of	persons	conducting	trawl	

Latitude/longitude	start	 Latitude	 Longitude	 Record	as	XXX.XXXX	at	start	of	the	sample	

transect	(decimal	degrees)	

Latitude/longitude	end	 Latitude	 Longitude	 Record	as	XXX.XXXX	at	end	of	the	sample	

transect	(decimal	degrees)	

Time	 Start	 End	 Record	as	HH:MM.		Record	when	flowmeter	

starts	/	stops	turning.	

Time	(adjusted)	 Start	 End	 Any	adjustments	to	the	actual	trawl	time,	in	

seconds,	based	on	eployment/recapture	of	

net.			

Flowmeter		 Start	 End	 Flowmeter	reading	(xxxxxx)	before	and	after	

trawl	

Average	ship	speed	 Record	in	knots	

Photo	ID	#s	 The	digital	identification	number(s)	of	debris	

photos	taken	during	this	transect.	
DEBRIS DATA:		

ITEM	 TALLY	(e.g.,	IIII)	 TOTAL		

PLASTIC

Plastic	fragments	 Hard Foamed Film	

Food	wrappers	 	 	

Beverage	bottles	

Other	jugs	or	containers	

Bottle	or	container	caps	

Cigar	tips	

Cigarettes	

Disposable	cigarette	lighters	

6‐pack	rings	

Bags	

Plastic	rope/small	net	pieces	

Buoys	&	floats	

Fishing	lures	&	line	

Cups	(including	polystyrene/	

foamed	plastic)	

Plastic	utensils	

Straws	

Balloons	

Personal	care	products	

Other:	

METAL

Aluminum/tin	cans	

Aerosol	cans	

Metal	fragments	

Other:	

GLASS

Beverage	bottles	

Jars	

Glass	fragments	

Other:	

RUBBER

Flip‐flops	

Gloves	

Tires	

Rubber	fragments	

Other:	

PROCESSED LUMBER (no natural wood)

Cardboard	cartons	 	 	

Paper	and	cardboard	

Paper	bags	

Lumber/building	material	

Other:	

 
ITEM	 TALLY	(e.g.,	IIII)	 TOTAL	

CLOTH/FABRIC

Clothing	&	shoes	

Gloves	(non‐rubber)	

Towels/rags	

Rope/net	pieces	(non‐nylon)	

Fabric	pieces	

Other:	

OTHER/UNCLASSIFIABLE

LARGE DEBRIS ITEMS (> 1 foot or ~ 0.3 m)

Material	type	

(e.g.,	plastic)

Item	type	

(e.g.,	net)	

Approximate	

width	(m)	

Approximate	

length	(m)	

Description	/		

photo	ID	#	

Notes	on	debris	items,	description	of	“Other/unclassifiable”	items,	etc:	

Sea state: BEAUFORT WIND FORCE SCALE: Specifications and equivalent speeds for use at sea

FORCE	 EQUIVALENT	

(miles/hr)	

SPEED	

(knots)	

WAVE	

(m)	

DESCRIPTION

0	 0‐1	 0‐1	 0	 Calm Sea	like	a	mirror

1	 1‐3	 1‐3	 .1	 Light	Air	 Ripples	with	the	appearance	of	scales	are	formed,	but	without	foam	crests.

2	 4‐7	 4‐6	 .2	 Light	Breeze	 Small	wavelets,	still	short,	but	more	pronounced.	Crests	have	a	glassy	appearance	and	do	not	break.

3	 8‐12	 7‐10	 .6	 Gentle	Breeze	 Large	wavelets.	Crests	begin	to	break.	Foam	of	glassy	appearance.	Perhaps	scattered	white	horses.

4	 13‐18	 11‐16	 1	 Moderate	Breeze Small	waves,	becoming	larger;	fairly	frequent	white	horses.	

5	 19‐24	 17‐21	 2	 Fresh	Breeze	 Moderate	waves,	taking	a	more	pronounced	long	form;	many	white	horses	are	formed.	Chance	of	some	

spray.	

6	 25‐31	 22‐27	 3	 Strong	Breeze	 Large	waves	begin	to	form;	the	white	foam	crests	are	more	extensive	everywhere.	Probably	some	spray.

7	 32‐38	 28‐33	 4	 Near	Gale	 Sea	heaps	up	and	white	foam	from	breaking	waves	begins	to	be	blown	in	streaks	along	the	direction	of	

the	wind.	

8	 39‐46	 34‐40	 5.5	 Gale	 Moderately	high	waves	of	greater	length;	edges	of	crests	begin	to	break	into	spindrift.	The	foam	is	blown	

in	well‐marked	streaks	along	the	direction	of	the	wind.	

9	 47‐54	 41‐47	 7	 Severe	Gale	 High	waves.	Dense	streaks	of	foam	along	the	direction	of	the	wind.	Crests	of	waves	begin	to	topple,	

tumble	and	roll	over.	Spray	may	affect	visibility.	

10	 55‐63	 48‐55	 9	 Storm	 Very	high	waves	with	long	over‐hanging	crests.	The	resulting	foam,	in	great	patches,	is	blown	in	dense	

white	streaks	along	the	direction	of	the	wind.	On	the	whole	the	surface	of	the	sea	takes	on	a	white	

appearance.	The	'tumbling'	of	the	sea	becomes	heavy	and	shock‐like.	Visibility	affected.	

11	 64‐72	 56‐63	 11.5	 Violent	Storm	 Exceptionally	high	waves	(small	and	medium‐size	ships	might	be	for	a	time	lost	to	view	behind	the	

waves).	The	sea	is	completely	covered	with	long	white	patches	of	foam	lying	along	the	direction	of	the	

wind.	Everywhere	the	edges	of	the	wave	crests	are	blown	into	froth.	Visibility	affected.	

12	 73‐83	 64‐71	 14+	 Hurricane	 The	air	is	filled	with	foam	and	spray.	Sea	completely	white	with	driving	spray;	visibility	very	seriously	

affected.	
PELAGIC DEBRIS

Large Debris Data Sheet

Organization	 Name	of	organization	responsible	

for	collecting	the	data	

Surveyor	Name	 Name	of	person	responsible	for	

filling	in	this	sheet	

Phone	Number	 Phone	contact	for	surveyor	

Completed	for	large	items	

collected	OR	lost	(excluded)	

from	net	tows			

Date	 Date	of	this	survey	

Body	of	water,	

location	

Name	by	which	the	body	of	water	is	

known	

Large Debris Data:

Item	Type	

(vessel,	net,	

etc.)	

Status	

(CAPTURED	

in	net	vs.	

EXCLUDED	

from	net	in	

ship	path)	

Trawl	

#	

Trawl	

Latitude	

(nnn.nnnn	

N)	

Trawl	

Longitude	

(nnn.nnnn	

W)	

Approximate	

Area	

Photo	

ID/#	 Length	 Description	

(ft)	

Width	

(ft)	

	 		 	 				

	 		 	 				

	 		 	 				

	 		 	 				

	 		 	 				

	 		 	 				
67 

7.5.3 Visual survey data sheets 

This data sheet is also available on the NOAA website. 

http://www.corporateservices.noaa.gov/~noaaforms/eforms/nf75-103.pdf
Shipboard Observation Form for Floating Marine Debris

Transect line START: Time (01:00‐24:00 UTC): ___________ Heading: ________°

Latitude: _______°____.____' N Longitude: _______°____.____' W 2 knots 6 

Transect line END: Time (01:00‐24:00 UTC): ___________ Heading: ________° 6 m 

Latitude: _______°____.____' N Longitude: _______°____.____' W 8 m 

Did your heading change between your start and end time? YES (Note heading changes below) NO 10 m 

Heading change #1: Time of change (01:00‐24:00 UTC): ___________ Heading: _____________° 15 m 

Heading change #2: Time of change (01:00‐24:00 UTC): ___________ Heading: _____________°

Heading change #3: Time of change (01:00‐24:00 UTC): ___________ Heading: _____________°

Other

Buoys/ Floats

Misc Line

Misc. Nets

Other Fishing Gear

Plastic Fragment

Bags, Sheeting, Tarp

Bottles (Beverage)

Jugs/ Buckets

Styrofoam

Other Plastic Item

Glass Bottle

Other Glass Item

*Describe

(e.g., processed

lumber)

Turtles? (Y or N)

Jellyfish? (Y or N)

Seabirds? (Y or N)

Avg wind speed

(knots)

Avg boat speed

(knots)

Weather (describe)

Cloud cover (% of

the overhead sky

covered in clouds)

Avg sea state

(describe)

P I 0 0 0 III 0 I 0 I 0 II 0 -- N N N 5 10 sunny/ clear 5% calm 

No 

Sh

1 m

3 m

6 m

10 m

Observer height

above water

In

cha

pa

Observations from PORT or

STARBORD side?

Fishing/Boat Gear

Height of obs. above water (m):

Vessel Speed:

DIRECTIONS:1. Determine transect width based on observer height above water and ship speed (see Table)

2. Record ancillary data and start and end lat/long and time.

3. Log debris (> than 2.5 cm) spotted on one side of the vessel (port or starboard) within transect width.

Observer Name:

Transect width:

Plastics Glass Wildlife

Date: Month/Day/Year Vessel Name:

SPEED / WEATHER / SEA STATE
69 

7.6 Marine Debris Survey Photo Manual 






 
77 

7.7 Frequently Asked Questions for Shoreline Surveys 
78 

Shoreline Survey Frequently Asked Questions 

General 

Q: Our volunteers cannot make the regularly scheduled survey. How should we reschedule the 

survey? 

Q: How many photos should be taken at each survey? 

Q: How do I keep track of the date on which photos were taken? 

Q: My GPS is giving me lat/longs in the wrong format, how do I change it to decimal degrees? 

Shoreline Characterization 

Q: If my shoreline is greater than six meters wide, I need to record GPS coordinates at all four 

corners of survey site. How do I take GPS coordinates at the water’s edge when waves are washing 

in and out? 

Q: How do I determine the tidal distance? 

Q: My shoreline site is longer than 100 m. How do I select a 100 m segment? 

Q: How do I determine the back of the shoreline? 

Survey Protocols 

Q: I found an item of debris smaller than 2.5 cm in the longest dimension. Why can’t I record it on 

the data sheet? 

Q: I found an item that could become a large item (> 30 cm) if it became unraveled / unwound. How 

should I record it? 

Q: Do surveys always need to be conducted at low tide? 

Q: Why do we need to measure beach width at every survey? 

Q: How do you record the width of the site if the back of the shoreline is not parallel to the water 

(e.g., a U-shaped site)? 

Q: What should I do if I cannot determine the debris material type? 

Q: I found a piece of natural driftwood. Should I record this on the survey sheet?

Q: I found an item that is coated in one material type, and composed of another. How do I record it? 

Q: I found multiple pieces of a larger piece of debris. Should I record it as one item or multiple 

items? 

Q: There is debris beyond the first barrier or change in substrate at the back of the shoreline. Can I 

record those items? 

Q: What should I do if I find debris fouled with what might be invasive species? 

Q: What should I do if I find a piece of hazardous debris? 

Q: What should I do if I find a derelict vessel or other large object that may become a hazard to 

navigation? 

Q: What should I do if I find an item that may be a valuable or significant memento? 

Q: I am completing standing-stock surveys. Why do I need to take GPS coordinates of all four 

transects at every survey? 

Q: I am completing standing-stock surveys, and at multiple surveys I have been encountering the 

same item. Should I tally this item at each survey (assuming it is in one of the random transects)? 

Data Entry and Submission 

Q: How do I get access to the NOAA MD-MAP database? 

Q: How often should I upload data to the NOAA MD-MAP database? 
79 

General 

Q: Our volunteers cannot make the regularly scheduled survey. How should we reschedule the 

survey?

A: Surveys should be conducted on a regular, every 28 day schedule. If you need to miss a survey it 

should be made up within a three day window of the original survey date (i.e., 28 days ± 3 days). 

That gives you a seven day window for completing the missed survey. 

Q: How many photos should be taken at each survey?

A: Taking a photo of the entire site from the beginning and end points at each survey is a good way 

to visually capture changes in shoreline topography and other characteristics that may affect debris 

deposition. You may also want to take a photo of each individual transect. In addition, please take 

photos of interesting, unidentifiable, or fouled debris (organisms growing on or attached to debris). 

Q: How do I keep track of the date on which photos were taken?

A: You should download the photos to your computer following each survey. Change the filename of 

the photos to include a date, location, and photo # (e.g., 06-10-2012_LongBeach#01.jpg). You can 

also write comments about the photos you’ve taken in the notes section of the data sheet. 

Q: My GPS is giving me lat/longs in the wrong format, how do I change it to decimal degrees? 

A: The lat/long units can be usually be changed in the general settings of the GPS. There are also 

many online tools to convert between units. 

Shoreline Characterization 

Q: If my shoreline is greater than six meters wide, I need to record GPS coordinates at all four 

corners of survey site. How do I take GPS coordinates at the water’s edge when waves are washing 

in and out?

A: When you conduct your initial shoreline characterization it is important to arrive at the site at low 

tide so that you can capture the entire width of the beach. In order to record GPS readings at the 

water’s edge, watch the breaking waves to try to determine the shoreward extent of the water. Record 

coordinates at that point. If a portion of the shoreline site is underwater at subsequent surveys do not 

try to enter the water to survey. Only survey the exposed area of the shoreline. 

Q: How do I determine the tidal distance?

A: Tidal distance is the horizontal distance on the beach between the average low and high tide lines. 

Arrive at your site at low tide and measure the distance from the water’s edge to the high tide wrack 

line. This measurement is different from the total width of the shoreline, which is measured from the 

waters’ edge to the back barrier. 

Q: My shoreline site is longer than 100 m. How do I select a 100 m segment?

A: Select your 100 m segment based on areas with relatively low public usage, little evidence of 

debris from day use (picnic debris), and areas that are not immediately adjacent to an obstruction to 

nearshore circulation (e.g., breakwater, point of land). Also consider landmarks or permanent 

features to assist in returning to the same segment at future dates. You may want to consider 

randomly selecting multiple 100 m segments within a larger shoreline site. 

Q: How do I determine the back of the shoreline? 

A: The back of the shoreline is defined here as the first major change in substrate, which may be a 

vegetation line, cliff, or other barrier. If you are interested in also monitoring debris that may be 
80 

pushed back into vegetation behind the beach during storms, that debris should be tallied on a 

separate data sheet so that it's not included in the calculated debris standing-stocks. Data entered into 

the NOAA database should only reflect the debris to the first change in substrate. If the back of the 

shoreline is only a partial barrier, for example a patch of vegetation behind which there is more 

beach, then survey up to the first continuous barrier (include that vegetation patch and the area 

behind it). In some cases, shoreline sites may be too complex to clearly delineate a maximum 

landward limit where debris might be deposited. These types of sites, and shorelines that are very 

high energy or dominated by sedimentary deposits, may not be good shoreline survey candidates. For 

the same reason, barrier islands and other shifting substrates are not likely to be ideal survey 

locations. 

Survey Protocols 

Q: I found an item of debris smaller than 2.5 cm in the longest dimension. Why can’t I record it on 

the data sheet?

A: The 2.5 cm size cutoff (about the size of a bottle cap) is used as a standard metric because it is the 

smallest size that can reliably and consistently be detected with the human eye. 

Q: I found an item that could become a large item (> 30 cm) if it became unraveled / unwound. How 

should I record it? 

A: Items should be recorded according to how they’re found at the time of the survey. For example, 

if a circular strap or band is found enclosed and is < 30 cm in all dimensions it should be recorded as 

a regular-sized item, but if it is opened / detached and is longer than 30 cm, it should be recorded as a 

large item. 

Q: Do surveys always need to be conducted at low tide?

A: The NOAA protocols ask for surveys to be conducted at low tide so that the entire area where 

debris may be deposited is surveyed. However, in some areas where tidal ranges are measured in 

10’s of meters, it may not be practical to survey at low tide when large mud flats or wave-cut 

platforms are exposed. If it becomes apparent that the vast majority of debris in the intertidal is 

ultimately pushed up to the high tide wrack line, surveyors may decide that it is valid to survey at 

times outside of the suggested window. However, this decision should be made carefully, backed up 

with data, and revisited on a regular basis. 

Q: Why do we need to measure beach width at every survey? 

A: Knowing the width of the shoreline allows NOAA to report debris densities in units of # of items 

per square meter of shoreline. NOAA asks for the shoreline width at each survey in order to evaluate 

the variability in shoreline width over the course of the project. Ideally, you could note the shoreline 

width at the average lowest tide of the day (tidal height 0’ according to tide tables or graphs), referred 

to as Mean Lower Low Water (MLLW, more information available at: 

http://tidesandcurrents.noaa.gov/datum_options.html). 

Q: How do you record the width of the site if the back of the shoreline is not parallel to the water 

(e.g., a U-shaped site)?

A: If the shoreline site is irregularly shaped, you will need to measure the width in a few different 

places in order to get an accurate estimate of total shoreline area. Please sketch the shape of the site 

in the data sheet notes section. Break the shoreline into a series of rectangles and measure the length 

and width of each. This does not need to be done at every survey. 
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Q: What should I do if I cannot determine the debris material type?

A: If you don’t know whether an item is rubber, plastic, metal, etc., record it under “other”, provide a 

description, and take photos. 

Q: I found a piece of natural driftwood. Should I record this on the survey sheet? 

A: No. Natural woody debris does not fall under the official definition of marine debris. Only 

processed or treated lumber should be recorded. 

Q: I found an item that is coated in one material type, and composed of another. How do I record it? 

A: Items should be recorded according to the primary material type on the surface of the item. 

Q: I found multiple pieces of a larger piece of debris. Should I record it as one item or multiple 

items?

A: Record the item in the condition you found it. If the item was broken when you found it, record 

each piece separately. If it broke while you were examining it, record the debris as one item only. 

Q: There is debris beyond the first barrier or change in substrate at the back of the shoreline. Can I 

record those items?

A: Items located beyond the first barrier can be noted and described in the notes section of the data 

sheet (or on a separate data sheet), but this data should be compiled separately from the shoreline 

debris data. 

Q: What should I do if I find debris fouled with what might be invasive species?

A: If you suspect that you may have found debris with invasive species, please take clear photos of 

the item, attached organism, and any identifying marks on the object. Remove the item from the 

water or shoreline and place on dry land well above the high tide line. You may want to contact local 

taxonomic experts listed at http://www.anstaskforce.gov/Tsunami.html. In your report note the 

current location of the item. 

Q: What should I do if I find a piece of hazardous debris? 

A: If you encounter hazardous items such as oil or chemical drums, contact your local authorities (a 

911 call), state environmental health agency, and the National Response Center 1-800-424-8802. 

Provide as much information as possible so the authorities can determine how to respond. 

Q: What should I do if I find a derelict vessel or other large object that may become a hazard to 

navigation? 

A: Contact your local authorities (a 911 call), state environmental health agency, and the U.S. Coast 

Guard Pacific Area Command at 510-437-3701. Provide as much information as possible so the 

authorities can determine how to respond. 

Q: What should I do if I find an item that may be a valuable or significant memento? 

A: If an item has unique identifiers and may be traceable to an individual or group, please take 

photos and report the item to DisasterDebris@noaa.gov (note that the item was found during a 

monitoring survey). Use your best judgment to determine what may or may not be valuable. 

Q: I am completing standing-stock surveys. Why do I need to take GPS coordinates of all four 

transects at every survey?

A: Taking GPS coordinates of each transect helps NOAA to track the location of transects and to 

ensure that the survey site location is not changing over time (due to moving landmarks or shifting 
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beach dynamics). Additionally, it helps to ensure that site start/end points are located correctly and 

that equipment is functioning properly. 

Q: I am completing standing-stock surveys, and at multiple surveys I have been encountering the 

same item. Should I tally this item at each survey (assuming it is in one of the random transects)?

A: Yes! This is part of the reason that standing-stock surveys are informative. They provide 

information on the density of debris on the shoreline and how it changes over time. Debris that 

remains on the shoreline for long periods of time is part of the “standing-stock.” The persistence of 

the item can be noted in the notes section of the data sheet. 

Data Entry and Submission 

Q: How do I get access to the NOAA MD-MAP database?

A: Send an email to MD.monitoring@noaa.gov for questions about the database or to request a login. 

Q: How often should I upload data to the NOAA MD-MAP database?

A: Please enter data into MD-MAP as soon as possible after each survey to ensure that data is 

entered accurately. 
Penny Pritzker

United States Secretary of Commerce

Dr. Kathryn D. Sullivan

Acting Under Secretary of Commerce for Oceans and Atmosphere

Dr. Holly A. Bamford

Assistant Administrator, National Ocean Service