Sea turtles of all species are succumbing to a rising wave of trash in oceans and on beaches, according to a global survey of plastic marine pollution conducted by researchers at the University of Exeter in the United Kingdom.

The survey found turtles are being tangled up in lost fishing nets, plastic twine and nylon fishing line, as well as six pack rings from canned drinks, plastic packaging straps, plastic balloon string, kite string, plastic packaging and discarded anchor line and seismic cable. Turtles were also discovered entangled in discarded plastic chairs, wooden crates, weather balloons and boat mooring line.

The research, covering the major oceans where turtles live, found that 91 percent of entangled turtles were found dead. Those that survived often suffered serious wounds from entanglement, leading to maiming, amputation or choking. Others were forced to drag rubbish or debris with them.

A greater threat than oil spills

“We found, based on beach strandings, that more than 1,000 turtles are dying a year after becoming tangled up, but this is almost certainly a gross underestimate,” said Brendan Godley, professor of Conservation Science and director of the University of Exeter’s Centre for Ecology and Conservation and the lead author of the study. “Experts we surveyed found that entanglement in plastic and other pollution could pose a long term impact on the survival of some turtle populations and is a greater threat to them than oil spills.

“We need to cut the level of plastic waste and pursue biodegradable alternatives if we are to tackle this grave threat to turtles’ welfare.”

Hatchlings and young sea turtles are particularly susceptible to getting tangled up in lost or discarded fishing gear or floating debris, researchers said. Juvenile turtles ride on ocean currents to zones where floating rubbish and debris is concentrated creating an “ecological trap.” They also “set up home” near floating debris and can remain there for years.
The toll of ‘ghost fishing’

Most entanglements recorded were in lost or discarded fishing gear known as ‘ghost fishing’ rope, nets and lines. Since the 1950s the fishing industry has replaced natural fibers such as cotton, jute and hemp with synthetic plastic materials such as nylon, polyethylene and polypropylene which do not degrade in water.

Sea turtles, of course, aren’t the only marine species affected by lost plastic fishing line. Right whales, which had staged a recovery after centuries of whaling pressure, are back on the brink as a result of increasing ship collisions and entanglement with fishing lines.