Bottom-trawling techniques leave different traces on the seabed

Trawling boat sitting on open ocean.

Fishing fleets around the world rely on nets towed along the bottom to capture fish. Roughly one-fifth of the fish eaten globally are caught by this method, known as bottom trawling, which has been criticized for its effects on the marine environment. An international group has taken a close look at how different types of bottom trawling affect the seabed. It finds that all trawling is not created equal — the most benign type removes 6 percent of the animal and plant life on the seabed each time the net passes, while the most other methods remove closer to a third. 

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UW oceanography senior finds plastic microfibers are common on Puget Sound beaches

As part of a yearlong project, Frances Eshom-Arzadon visited 12 Puget Sound beaches to tally the number of nearly invisible bits of plastic, or microplastics. While the School of Oceanography major found Seattle-area beaches to be clean compared to some — on the Mediterranean Sea, for example — they’re still far from pristine. Her findings also suggest that polar fleece and other synthetic fibers are the main source of plastic fragments on local shores. 

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Distant earthquakes can cause underwater landslides

Paul Johnson headshot

New research finds that large earthquakes can trigger underwater landslides thousands of miles away, weeks or months after the quake occurs. Researchers analyzing data from ocean-bottom seismometers off the Washington-Oregon coast tied a series of underwater landslides on the Cascadia Subduction Zone to a 2012 magnitude-8.6 earthquake in the Indian Ocean — more than 8,000 miles away. These underwater landslides occurred intermittently for nearly four months after the April earthquake. 

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