The marine debris data included in this dataset are from annual shoreline surveys conducted from 2013 to 2016 at the islands of Midway Atoll (Eastern, Spit, and Sand Islands) in the Northwestern Hawaiian Islands (NWHI) by the NOAA Pacific Islands Fisheries Science Center (PIFSC), Ecosystem Sciences Division (ESD) with funding from Papahānaumokuākea Marine National Monument (PMNM), and NOAA's Marine Debris (MDP) and Damage Assessment Remediation and Restoration (DARRP) Programs. Prior to the surveys in 2013, each shoreline was divided into fixed 300-meter segments and stratified by the cardinal direction the shoreline was facing (e.g., north, south, east, and west). The shorelines of Eastern, Spit, and Sand Islands were divided into 19, 4, and 23 segments, respectively. All segments were surveyed at all islands during the 2013, 2015, and 2016 missions. During the 2014 mission, limited time was available to survey all segments; therefore, the pre-existing segments were randomized, and a subset of the segments were identified as a first- or second-tier priority for each strata. All first- and second-tier priority segments were surveyed in 2014. During a shoreline survey, field staff flagged the corners of the site and swept the entire survey area for marine debris. Most items found within the survey area >10 cm were collected and, if possible, bagged. Due to operational concerns, metal, glass, and building material were not surveyed or removed. Debris items <10 cm were also collected and bagged if the item could be identified (e.g., bottle caps and lighters were included in the survey, unidentified fragments <10 cm were typically excluded). Additionally, if the debris item was considered large (>1 m) or notable, a GPS waypoint was taken to mark the specific location of the debris, and the item was measured (length and width), recorded on the datasheet, and either bagged, removed, or tagged if the item was too large or hazardous to remove. The survey concluded by walking the perimeter of the survey site with a GPS. Following the survey, bagged and large debris were transported to the operations center for the mission, weighed, and sorted, tallied, and recorded by debris type for each survey. Total weight of all collected debris and the survey area (derived from the GPS tracks) were recorded for each 300-m segment, along with the date since the last debris survey to calculate the accumulation rate. During an extended field season at Midway Atoll in the NWHI in 2012, PIFSC scientists removed all of the marine debris along the shorelines of the islands at Midway Atoll. This represented a "clean slate" and starting point to begin studying the accumulation rate along the shorelines for subsequent years. Accumulation rates are reliable only for Eastern and Spit Islands. The shorelines of Sand Island are cleaned regularly by permanent U.S. Fish and Wildlife Service residents; thus, the debris data recorded by ESD for Sand Island does not represent natural accumulation. The shoreline survey and removal efforts at Midway Atoll have been conducted as a component of ship-based missions to the NWHI, a component of a larger shore-based missions at Midway Atoll, or as a stand-alone shoreline debris removal mission at Midway Atoll.

The marine debris data included in this dataset are from annual shoreline surveys conducted from 2013 to 2018 at the islands of Midway Atoll (Eastern, Spit, and Sand Islands) in the Northwestern Hawaiian Islands (NWHI) by the NOAA Pacific Islands Fisheries Science Center (PIFSC), Ecosystem Sciences Division (ESD) with funding from Papahanaumokuakea Marine National Monument (PMNM), and NOAA's Marine Debris (MDP) and Damage Assessment Remediation and Restoration (DARRP) Programs. Prior to the surveys in 2013, each shoreline was divided into fixed 300-meter segments and stratified by the cardinal direction the shoreline was facing (e.g., north, south, east, and west). The shorelines of Eastern, Spit, and Sand Islands were divided into 19, 4, and 23 segments, respectively. All segments were surveyed at all islands during the 2013, 2015, and 2016 missions. During the 2014 mission, limited time was available to survey all segments; therefore, the pre-existing segments were randomized, and a subset of the segments were identified as a first- or second-tier priority for each strata. All first- and second-tier priority segments were surveyed in 2014. All first- and second-tier priority segments at Eastern and Spit were surveyed in 2018. During a shoreline survey, field staff flagged the corners of the site and swept the entire survey area for marine debris. Most items found within the survey area >10 cm were collected and, if possible, bagged. Due to operational concerns, metal, glass, and building material were not surveyed or removed. Debris items <10 cm were also collected and bagged if the item could be identified (e.g., bottle caps and lighters were included in the survey, unidentified fragments <10 cm were typically excluded). Additionally, if the debris item was considered large (>1 m) or notable, a GPS waypoint was taken to mark the specific location of the debris, and the item was measured (length and width), recorded on the datasheet, and either bagged, removed, or tagged if the item was too large or hazardous to remove. The survey concluded by walking the perimeter of the survey site with a GPS. Following the survey, bagged and large debris were transported to the operations center for the mission, weighed, and sorted, tallied, and recorded by debris type for each survey. Total weight of all collected debris and the survey area (derived from the GPS tracks) were recorded for each 300-m segment, along with the date since the last debris survey to calculate the accumulation rate. During an extended field season at Midway Atoll in the NWHI in 2012, PIFSC scientists removed all of the marine debris along the shorelines of the islands at Midway Atoll. This represented a "clean slate" and starting point to begin studying the accumulation rate along the shorelines for subsequent years. Accumulation rates are reliable only for Eastern and Spit Islands. The shorelines of Sand Island are cleaned regularly by permanent U.S. Fish and Wildlife Service residents; thus, the debris data recorded by ESD for Sand Island does not represent natural accumulation. The shoreline survey and removal efforts at Midway Atoll have been conducted as a component of ship-based missions to the NWHI, a component of a larger shore-based missions at Midway Atoll, or as a stand-alone shoreline debris removal mission at Midway Atoll.

Supporting information documents for Brignac et al manuscript entitled, "Marine Debris Polymers on Main Hawaiian Island Beaches, Sea Surface, and Seafloor." Files include raw data tables of each debris item that was categorized and measured as well as additional figures of interpreted data.

Marine debris records from beaches on Heard and Macquarie Islands and floating debris spotted on voyages. Data were collected by observers surveying beaches either methodically or opportunistically, and by observers spotting debris as it floated past ships. The data were originally collated into a searchable database, but the application is no longer supported by the Australian Antarctic Data Centre. An extract of the data is attached to this metadata record. The extract is in Excel format, and each worksheet is a copy of a database table.

This dataset was derived from CAD data originally published in URS Greiner Woodward Clyde, 1999, : Former U.S. Coast Guard LORAN Station, Tern Island, French Frigate Shoals, Hawaii. URS Greiner Woodward Clyde (URSGWC) was retained by the United States Coast Guard (USCG) Civil Engineering Unit (CEU) to conduct an environmental investigation at the former USCG long range navigation (LORAN) station on Tern Island. The investigation concentrated on the northwestern corner of Tern Island where the greatest environmental impact from the US military's past occupation of the island appears to have occurred.

The natural resiliency of the New Jersey barrier island system, and the efficacy of management efforts to reduce vulnerability, depends on the ability of the system to recover and maintain equilibrium in response to storms and persistent coastal change. This resiliency is largely dependent on the availability of sand in the beach system. In an effort to better understand the system's sand budget and processes in which this system evolves, high-resolution geophysical mapping of the sea floor in Little Egg Inlet and along the southern end of Long Beach Island near Beach Haven, New Jersey was conducted from May 31 to June 10, 2018, followed by a sea floor sampling survey conducted from October 22 to 23, 2018, as part of a collaborative effort between the U.S. Geological Survey and Stockton University. Multibeam echo sounder bathymetry and backscatter data were collected along 741 kilometers of tracklines (approximately 200 square kilometers) of the coastal sea floor to regionally define its depth and morphology, as well as the type and distribution of sea-floor sediments. Six hundred ninety-two kilometers of seismic-reflection profile data were also collected to define the thickness and structure of sediment deposits in the inlet and offshore. These new data will help inform future management decisions that affect the natural and recreational resources of the area around and offshore of Little Egg Inlet. These mapping surveys provide high-quality data needed to build scientific knowledge of the evolution and behavior of the New Jersey barrier island system.

The natural resiliency of the New Jersey barrier island system, and the efficacy of management efforts to reduce vulnerability, depends on the ability of the system to recover and maintain equilibrium in response to storms and persistent coastal change. This resiliency is largely dependent on the availability of sand in the beach system. In an effort to better understand the system's sand budget and processes in which this system evolves, high-resolution geophysical mapping of the sea floor in Little Egg Inlet and along the southern end of Long Beach Island near Beach Haven, New Jersey was conducted from May 31 to June 10, 2018, followed by a sea floor sampling survey conducted from October 22 to 23, 2018, as part of a collaborative effort between the U.S. Geological Survey and Stockton University. Multibeam echo sounder bathymetry and backscatter data were collected along 741 kilometers of tracklines (approximately 200 square kilometers) of the coastal sea floor to regionally define its depth and morphology, as well as the type and distribution of sea-floor sediments. Six hundred ninety-two kilometers of seismic-reflection profile data were also collected to define the thickness and structure of sediment deposits in the inlet and offshore. These new data will help inform future management decisions that affect the natural and recreational resources of the area around and offshore of Little Egg Inlet. These mapping surveys provide high-quality data needed to build scientific knowledge of the evolution and behavior of the New Jersey barrier island system.

Seabeach amaranth (Amaranthus pumilus) is a federally threatened plant species that was once prevalent on beaches of the U.S. mid-Atlantic coast. To re-establish a population at Assateague Island National Seashore (ASIS), seabeach amaranth cultivars were planted by ASIS natural resources staff for three growing seasons from 1999 to 2001 and have been monitored since 2001. Characteristics of favorable seabeach amaranth locations were assessed by sampling barrier island and habitat characteristics at sites where plants are and are not observed in 2008, 2010, and 2014. These data can then be used to develop probabilistic models that provide maps of habitat suitability to identify high-priority areas for amaranth protection. The modeling effort also helps to inform management decisions that are most likely to result in the protection of a long-term sustainable population.