MARINE DEBRIS - Marine Pollution: What Everyone Needs to Know - page 47

(ROVs) on the bottom of the deep Monterey Canyon. In this
region, researchers noted over 1,150 pieces of debris on the sea-
floor. About one-third was plastic objects, and of these more
than half were plastic bags. Metal was the second most com-
mon type of debris; about two-thirds were cans of aluminum
or steel. Other common debris included rope, fishing equip-
ment, glass bottles, paper, and cloth. The trash was concen-
trated on steep rocky slopes. Surprisingly, it was common in
the deeper parts of the canyon, below 2,000 meters (6,500 feet).
In the same areas where trash accumulated, there was also
wood and other natural debris that originated on land, lead-
ing researchers to conclude that much of the trash came from
land-based sources rather than ships. Previous studies under-
estimated the extent of marine debris in the deep due to lack
of technology for observing deep bottoms. In another study,
microplastics were found in remote deep-sea sediments col-
lected at locations ranging in depth from 1,100 to 5,000 meters.
Researchers collecting samples in the Southern Ocean that
encircles Antarctica have detected high levels of plastic pollu-
tion in an area that was considered unspoiled. Similarly, the
sea bed in the Arctic deep sea is becoming covered with litter.
Photographs taken to investigate biodiversity of sea life pro-
vided evidence of increasing debris. Waste, primarily plastic,
was seen in 1% of the images from 2002, but in the images from
2011 it had doubled. While 2% does not seem like much, the
deep-sea Arctic Ocean has been considered to be one of the
most remote and pristine parts of the oceans.
Granted it is ugly, but can the litter harm marine life?
Effects of marine litter are primarily physical rather than
chemical. Debris that washes in and covers salt marshes or
mangroves injures the plants, the base of the food web in these
tidal wetlands. Injuries and subsequent recovery depend on
the extent and type of debris. Marine debris affects animals
through ingesting it or getting entangled in it; it is estimated