Accumulation Of Marine Debris Research Articles

Accumulation of Marine Debris on an Intertidal Beach in an Urban Park (Halifax Harbour, Nova Scotia)

Abstract This study evaluated monthly accumulation rates and types of marine debris washed ashore at a recreational beach in Point Pleasant Park, Halifax Harbour, between April and September 2005. Black Rock Beach is 70 m long and a total of 2129 marine debris items were collected and sorted, representing a mean accumulation rate of 355 (±68 SE) items month-1. The total weight of debris items was only 10.8 kg (mean 2 kg ±0.4 SE), however eighty-six percent of this debris was plastic material. The types of litter found included: tampon applicators, condoms (i.e., sewage-related debris [SRD]); plastic fast food packaging, confectionary wrappers, Styrofoam fragments, plastic bottles and caps, items of clothing, soft drink cans, cigarettes and cigarette holders (i.e., recreational or land-based debris); packing bands, nylon rope and nets (i.e., shipping- or fishing-related debris). These items were generated by recreational use of the park (52%), sewage disposal (14%) and from shipping and fishing activities (7%). It is suggested that a significant reduction in marine debris at recreational beaches may arise by improving public awareness of the environmental and aesthetic impacts of marine litter and future improvements to the municipal sewage disposal system.

Drifting plastic and its consequences for sessile organism dispersal in the Atlantic Ocean

Organisms have travelled the Atlantic Ocean as neuston and have rafted on natural marine debris for millions of years. Shipping increased opportunities for marine organism travel mere thousands of years ago but in just decades floating plastic debris is transforming marine rafting. Here we present a combined open-ocean and remote coasts marine debris survey of the Atlantic (from 68°S–78°N). Daily shipboard observations were made from the Southern Ocean to the high Arctic and the shores of 16 remote islands were surveyed. We report (1) anthropogenic debris from the most northerly and southerly latitudes to date, (2) the first record of marine biota colonising debris at latitudes >68°, and (3) the finding of exotic species (the barnacle Elminius modestus) on northern plastic debris. Plastic pieces dominated both open-ocean and stranding marine debris. The highest densities of oceanic debris were found around northwest Europe, whereas the highest stranding levels were equatorial. Our findings of high east-Arctic debris colonisation by fauna contrast with low values from west Arctic (though only two samples) and south Atlantic shores. Colonisation rates of debris differed between hemispheres, previously considered to be similar. Our two South Atlantic mega-debris shipboard surveys (10 years apart) found no changes in open-ocean debris densities but resurvey of a UK and an Arctic island both found increases. We put our findings in the context of the Atlantic literature to interpret spatial and temporal trends in marine debris accumulation and its organismal consequences.

Marine debris accumulation in the nearshore marine habitat of the endangered Hawaiian monk seal, Monachus schauinslandi 1999–2001

Large amounts of marine debris are present in shallow reefs adjacent to beach haulouts of the critically endangered Hawaiian monk seal, Monachus schauinslandi. These areas serve as seal pup nurseries, and injury and death caused by entanglement in marine debris are undermining population recovery efforts. We investigated the extent of this threat by measuring the accumulation of potentially entangling derelict fishing gear in nursery zones, 1999–2001. Plots of reef 1.0–1.3 km 2 at three Northwestern Hawaiian Islands were initially cleaned of derelict fishing gear in 1999 then resurveyed in 2000 and 2001. Submerged debris densities across sites ranged from 16 to 165 debris items/km 2. Resurveyed sites yielded annual marine debris accumulation rates from 0 to 141 debris items/km 2. This large range was attributed to the physiography of reef areas surveyed. Trawl net webbing was significantly more common than other types of debris recovered and represented 84% of all debris encountered, suggesting that much of the debris originated from distant North Pacific Ocean fisheries. The likely source of most debris is the multinational trawl fisheries of the North Pacific Ocean. An international solution to this problem is needed. Targeted marine debris removal is a short-term, successful, entanglement mitigation strategy.

A Pre- and Post-MARPOL Annex V Summary of Hawaiian Monk Seal Entanglements and Marine Debris Accumulation in the Northwestern Hawaiian Islands, 1982–1998

Entanglements of Hawaiian monk seals, Monachus schauinslandi, were documented in the northwestern Hawaiian Islands (NWHI) from 1982 to 1998, and debris which presented a threat of entanglement was inventoried and removed from 1987 to 1996. A total of 173 entanglements was documented. The number of entanglements did not change after implementation of MARPOL Annex V in 1989. Pups and juvenile seals were more likely to become entangled than older seals, and became entangled primarily in nets, whereas entanglement of subadults and adults was more likely to involve line. The subpopulation of seals at Lisianski Island experienced the most entanglements, although Lisianski did not accumulate the most debris. Localized high entanglement rates may gravely affect individual monk seal subpopulations. Accumulation of debris has not diminished since implementation of Annex V, nor has occurrence of derelict drift nets abated since a 1989 moratorium. Debris washing ashore has likely been circulating in the North Pacific Ocean for some time.

Rates of accumulation of marine debris in Chatham County, Georgia

Marine debris (persistent, solid marine pollution), especially plastics and medical wastes, is a growing concern of coastal communities. In Chatham County, Georgia marine pollution was studied over an eight-month period in 1989–1990 at four sites representing a variety of shoreline types. Anthropogenic solid materials (e.g. plastics, metals, glass) were collected in measured areas from the shoreline to highest high tide line, classified by type, measured to the nearest centimetre, and weighed to the nearest gram. From 2.38 km of shoreline 956 separate items weighing a total of 107.2 kg were collected. The equivalent of 94.4 kg marine debris per km was collected during the first sampling in October 1989. This amount was less than that reported by 12 of the 22 states participating in the 1989 Beachsweep effort. Overall, the rate of accumulation of marine debris in Chatham County, Georgia is 102 kg per km per year. Extrapolating this rate to the total estimated shoreline in Chatham County, 40 800 kg or 40.8 t of marine debris might wash up on its shores annually. No medical wastes were found at any of the sites during the study.