Plastic debris found at deep-water reef

Fragments of fishing equipment and microplastics have been found inside animals living on Scotland’s only inshore deep-water coral reef.

Scientists discovered tiny plastic fibres inside creatures including starfish and sea worms at the remote Mingulay Reef Complex, off the north-west coast.

The findings highlight how widespread ocean littering has become, according to the team from the University of Edinburgh.

The results come from analysis of preserved specimens collected from around the reef, a designated marine protected area, over the past 16 years.

“It’s really surprising to see the amount and range of microplastics in these deep reefs,” said Laura La Beur, a research student based at the university’s School of GeoSciences.

“We don’t yet know what impact small microfibres will have on the deep oceans, but caution is needed to prevent putting the seas under more stress.”

Professor Murray Roberts added: “It’s staggering to find our plastic waste has spread so far, to this remote and stunningly beautiful place.

“We need to not treat the ocean as our junkyard, and work to better understand what effect these tiny plastic fragments are having on marine life.”

The researchers found man-made debris at three of the reefs in the East Mingulay marine protected area.

The majority of records fell within the zoned area that now prohibits most forms of fishing, with the greatest proportion of litter categorised as fisheries-related.

Ingested particles were mainly microplastic fibres of 2mm to 5mm in length, with several types of polymers identified – including polypropylene, polyurethane, polystyrene and polyethylene terephthalate, or PET.

Larger items seen included tarpaulins and discarded fishing gear, which pose a high risk to sea life through entanglement or ensnaring – known as ghost fishing.

Mingulay Reef Complex covers around 100 square kilometres, with its oldest parts thought to be at least 4,000 years old.

The corals support a diverse range of marine life, providing a haven of food and shelter for deep-sea species.

The reef was recently identified as a spawning ground for the blackmouth catshark, which lays its eggs at depths of almost 200m.