The Papahanaumokuakea Marine National Monument includes the 1200 nautical mile chain of atolls and islets known as the Northwestern Hawaiian Islands (NWHI) that are geographically positioned as a repository for marine debris such as derelict fishing gear (DFG). Accidentally lost or intentionally abandoned DFG circulates within the North Pacific Subtropical Gyre until it encounters the atolls of the NWHI. When the floating DFG reaches these islets and atolls, wave energy forces it across coral reefs, snagging the assorted nets and lines upon corals. DFG may impact coral reef ecosystems in a number of other ways, including destroying coral reef habitat, acting as a vector for the introduction of non-native species, and presenting a hazard to boat navigation. Most notably, entanglement in DFG presents a lethal threat to the critically endangered Hawaiian monk seal (Monachus schauinslandi) and the threatened green sea turtle (Chelonia mydas). Supported by the Papahanaumokuakea Marine National Monument, NOAA's Marine Debris Program (MDP), NOAA's Damage Assessment Remediation and Restoration Program (DARRP), and NOAA's Coral Reef Conservation Program (CRCP), the marine debris team of the Coral Reef Ecosystem Division (CRED) at the Pacific Islands Fisheries Science Center (PIFSC) conducts cruises to the NWHI for the purpose of surveying and removing DFG. Exploratory and opportunistic efforts began in 1996 that eventually evolved into dedicated cruises deployed for up to 4 months at a time with a team of up to 16 divers. To date, CRED's marine debris team has removed approximately 822 metric tons of derelict fishing gear from the NWHI, including the atolls and islets of Pearl and Hermes Atoll (PHR), Midway Atoll (MID), Kure Atoll (KUR), Lisianski Island (LIS), Laysan Island (LAY), Maro Reef (MAR), and French Frigate Shoals (FFS). Surveys are conducted by divers based on small boats launched from a ship. Two survey methods are used to search for marine debris; tow survey and swim survey. Tow surveys are used in the relatively even-depth (usually less than 10 meters deep), contiguous backreef habitats, while swim surveys are used in the comparatively high-relief and patchy lagoonal reef habitats. Survey areas are chosen based on regional reef morphology and past accumulation records. In a tow survey, two freediving divers are towed behind a small boat at an average of 1-2 knots. Each diver has a board with which they maneuver through the water column in a vertical and horizontal serpentine pattern. The small-boat coxswain drives the boat in parallel tracks to cover the planned survey area. Tow tracks are recorded on a GPS unit that is set to record at 15 second intervals. Tow track survey lines are downloaded and converted to polygon features in ArcGIS using a 15 meter buffer (7.5 meters on each side) to represent area surveyed by the towed divers. The swim survey method, first used for NWHI marine debris detection in 2002, was developed as a necessary alternative to towed-diver surveys in lagoonal, reticulated reef areas that were either too shallow or too irregular to be surveyed effectively with the tow survey technique. The divers are directed by personnel in small boats to follow pre-planned routes. When a distinguishable reef has been surveyed, the small-boat coxswain drives a GPS-recorded track around that particular reef. These areas are digitized into polygon features in ArcGIS using a combination of the recorded tracks and IKONOS satellite imagery in which reef edges are visible in 4 meter resolution. When a diver encounters a piece of DFG during either type of survey, the diver notifies the coxswain to stop the boat and take a waypoint over the DFG. Descriptive data about the piece of DFG such as DFG type, DFG color, estimated depth, length/width/height (layout of DFG in the water as found by divers), foul level, presence/absence of coral growth on DFG (including growth type and coral genera), substrate composition/color and volume are recorded and maintained in an Oracle database. Waypoints are recorded for locations of DFG and are downloaded as shapefiles with attributes that include waypoint name, UTC date and time collected, Hawaii standard time collected, small boat label, GPS unit label, survey type (swim or tow), survey zone (high entanglement risk zone or standard), source (water or land) and an Item designation. Waypoint data for DFG is maintained in an Oracle database table that is linked to descriptive data about each point of DFG via a common waypoint name, date, and GPS unit label. In 2011, opportunistic land debris survey and removal efforts were conducted on all three of the Midway Islands; Sand Island, Eastern Island and Spit Island. From 2012-2014 the addition of planned land debris survey and removal efforts in all surveyable shoreline areas of all three of the Midway Islands; Sand Island, Eastern Island and Spit Island were conducted. During land debris efforts, shorelines were surveyed and all derelict fishing gear and plastic items larger than 10 cm were removed (with the exception of plastic bottle caps and lighters). The NOAA MDP-standardized shoreline survey datasheet was used to tally different debris types during the removal process. Additionally, one 100-m transect was established on each of the three islands in order to conduct the NOAA MDP Standing Stock survey for marine debris. Cruises target one or more of the atolls of the NWHI and vary in duration from one to four months. The following table displays the names of vessels that participated in research cruises each year and the atolls they visited, as well as the land-based efforts not associated with vessels. CALENDAR YEAR VESSEL NAME/LAND BASED MISSION ATOLLS VISITED CRUISE/MISSION REPORT (if available) 1999 NOAA Ship Townsend Cromwell LIS, PHR http://www.pifsc.noaa.gov/library/pubs/cruise/Townsend_Cromwell/CR9910-1.MJD.pdf 2000 NOAA Ship Townsend Cromwell FFS, KUR, LIS, PHR http://www.pifsc.noaa.gov/library/pubs/cruise/Townsend_Cromwell/CR0012-1.MJD.pdf 2001 American Islander, Ocean Fury, Katmai, Townsend Cromwell FFS, KUR, LIS, PHR 2002 American Islander, Ocean Fury FFS, KUR, LAY, LIS, MID, PHR 2003 American Islandr, Ocean Fury FFS, KUR, LAY, LIS, MAR, MID, PHR 2004 Casitas FFS, KUR, LAY, LIS, MAR, PHR 2005 Casitas, Freebird, USCG Ship Walnut, USCG Ship Kukui FFS, KUR, LAY, LIS, MAR, MID, PHR 2006 NOAA Ship Oscar Elton Sette, Land Based Midway Effort FFS, KUR, LAY, LIS, MID, PHR http://www.pifsc.noaa.gov/library/pubs/cruise/Sette/CR0609-KK.pdf 2007 NOAA Ship Oscar Elton Sette FFS, KUR, LAY, LIS, PHR 2008 USCG Ship Walnut MAR, MID 2009 NOAA Ship Oscar Elton Sette, USCG Ship Walnut FFS, KUR, LAY, LIS, MAR, MID, PHR http://www.pifsc.noaa.gov/library/pubs/cruise/Sette/CR0908I-KK.pdf, http://www.pifsc.noaa.gov/library/pubs/cruise/Sette/CR0908II-KK.pdf 2011 NOAA Ship Oscar Elton Sette, Land Based Midway Effort FFS, KUR, LAY, LIS, MID, PHR http://intra.pifsc.gov/sites/default/files/SBR1102-KK.pdf (Internal PIFSC document) 2012 NOAA Ship Oscar Elton Sette, Land Based Midway Effort FFS, KUR, LAY, LIS, MID, PHR http://www.pifsc.noaa.gov/library/pubs/cruise/Sette/CR1204-KK.pdf, http://intra.pifsc.gov/sites/default/files/SBP1205-KK_0.pdf (Internal PIFSC document) 2013 Land Based Midway Effort MID Mission Plan: http://intra.pifsc.gov/sites/default/files/SB-13-05_Final_0.pdf (Internal PIFSC document) 2014 NOAA Ship Oscar Elton Sette FFS, LIS, MAR, MID, PHR (http://www.pifsc.noaa.gov/library/pubs/cruise/Sette/CR1407-MM.pdf) A high turnover rate of staff led to various data management styles over the history of the program, thus, the marine debris team undertook an effort to error-check and centralize all marine debris data into an Oracle Database, which was completed in April 2014. For more detailed information regarding specific cruises and the data collection process, contact CRED.
Survey area data are collected for maintaining a spatial record of surveyed versus unsurveyed habitat areas at locations in the Northwestern Hawaiian Islands. They are collected concurrently with marine debris point data, including attributes of both marine debris and the substrate upon which it was found. Waypoint data are collected for display and analysis of marine debris locations in the Northwestern Hawaiian Islands.
ground condition
These marine debris survey data act as a proxy for area surveyed and have not been screened for accuracy based on environmental conditions or GPS accuracy. NOAA can not be held liable for use of these data in a manner other than for perusal of preliminary marine debris data for scientific research on coral reef ecosystems. When using this data, please credit the Coral Reef Ecosystem Division, Pacific Islands Fisheries Science Center, National Marine Fisheries Service.
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NMFS/PIFSC/CRED
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Coral Reef Ecosystem Division (CRED), Pacific Islands Fisheries Science Center, NOAA National Marine Fisheries Service
These marine debris survey data are PRELIMINARY data and have not been screened for accuracy. NOAA can not be held liable for use of these data in a manner other than for perusal of preliminary marine debris data for scientific research on coral reef ecosystems. Disclaimer - NOAA makes no warranty regarding these data, expressed or implied, nor does the fact of distribution constitute such a warranty. NOAA cannot assume liability for any damages caused by any errors or omissions in these data, nor as a result of the failure of these data to function on a particular system.
locations of diver survey areas and marine debris points with unique identifiers of areas surveyed and marine debris point data
attribute information and descriptive data about each marine debris waypoint and piece of DFG
email nmfs.pic.credinfo@noaa.gov for inquiries and data.
