Scallops rebound in Scotland’s protected bay

King scallop in the reserve. (Credit: Howard Wood)

Surveys of Lamlash Bay, the site of Scotland’s first fully protected marine reserve, suggest the effort is paying off—both for fisheries and conservationists.

Backing from the local community has been crucial to the success of Lamlash Bay marine reserve after its creation off the Isle of Arran in 2008, following a decade-long campaign by the local Community of Arran Seabed Trust (COAST).

Lamlash Bay marine reserve
Lamlash Bay marine reserve with Holy Island in the background (Credit: Bryce Stewart)

The new study, published in Marine Biology, reports on monitoring surveys conducted in and around the marine reserve by scientists at the University of York from 2010 to 2013.

Over the course of the study, the abundance of commercially important juvenile scallops was consistently higher within the reserve than outside. These scallops were strongly associated with seaweeds and other marine life thriving on the seabed within the protected area.

Adult scallops showed benefits too. In particular, the size and reproductive capacity of scallops was much higher inside the reserve by the end of the study. The resultant high level of breeding within the reserve is likely to be seeding the surrounding fishing grounds.

“We found strong evidence that protecting Lamlash Bay from fishing has allowed seaweeds, hydroids, and other organisms on the seafloor to recover,” says Leigh Howarth, the study’s lead author who conducted the research as part of his PhD work. “These animals act as a magnet for settling juvenile scallops, which seek out these habitats for shelter, and to mature to adulthood.”

scuba diver
A scuba diver records the number of scallops observed within the reserve (Credit: Leigh Howarth)

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The results of the study come as fisheries for king and queen scallops have become some of the most important in the UK, generating more than £60 million first sale every year. Scientists have raised concerns over the damage to the seabed caused by the dredges and trawls normally used to catch them.

In other countries, such as the US, strategically placed protected areas have proved successful in protecting vulnerable areas of seabed while boosting the breeding and growth rates of scallops.

Both the English and Scottish governments have recently declared networks of marine protected areas (MPAs) around their coasts and are currently deciding on how to manage them. However, there are concerns that the preferred option of both governments is to do little to actually restrict fishing within these MPAs.

On the basis of this new research, and a growing number of other studies, this would be wasted opportunity, experts say.

Bryce Stewart, who supervised the work, adds: “Scallop fisheries are ideally suited to management using protected areas. This approach can protect sensitive habitats, which also act as nursery grounds for scallops and other species, while boosting the overall productivity of the fisheries.

“We urge the UK governments to create more highly protected areas, which can provide this win-win scenario for the management of our oceans.”

Source: University of York