A new study by Exeter University found that discarded plastic, derelict fishing gear and other man-made oceanic trash may pose a bigger threat to apex predators like sharks than previously thought.
The paper was published in the latest issue of the journal Endangered Species Research.
Entanglement—mostly involving lost or discarded fishing gear—is a “far lesser threat” to sharks and rays than commercial fishing, but the suffering it causes is a major animal welfare concern.
“One example in the study is a shortfin mako shark with fishing rope wrapped tightly around it,” said Kristian Parton, of the Centre for Ecology and Conservation on Exeter’s Penryn Campus in Cornwall.
“The shark had clearly continued growing after becoming entangled, so the rope—which was covered in barnacles—had dug into its skin and damaged its spine.
“Although we don’t think entanglement is a major threat to the future of sharks and rays, it’s important to understand the range of threats facing these species, which are among the most threatened in the oceans.
“Additionally, there’s a real animal welfare issue because entanglements can cause pain, suffering and even death.”
The problem might be even worse than indicated by the study since few studies have focussed on plastic entanglement among shark and rays.
The researchers have partnered with the Shark Trust to create an online report form to gather additional data. To report a sighting of sharks or rays that have been affected by entanglements with discarded trash and derelict fishing gear, click here: https://recording.sharktrust.org/entanglement/record