New research highlights how the estimated 50,000 wrecks around the UK coastline are protecting the seabed.

An estimated 50,000 shipwrecks can be found around the UK’s coastline and have been acting as a hidden refuge for fish, corals and other marine species in areas still open to destructive bottom towed fishing, a new study has shown.

Photo credit: marcusrose.gue

Many of these wrecks have been lying on the seabed for well over a century, and have served as a deterrent to fishers who use bottom towed trawling to secure their catches.

As a result, while many areas of the seabed have been damaged significantly in areas of heavy fishing pressure, the seabed in and around shipwrecks remains largely unblemished.

The new research found that the average density of marine life was 240% greater within wreck sites than in sites actively being used for bottom towed fishing.

In parts of the seabed within a 50m radius of the wrecks, the difference was even greater with the density of marine life 340% greater than in the control sites.

Conversely, in sites closed to trawling, the abundance was 149% greater than on wrecks and 85% greater than on the seabed within a 50m radius of the wrecks.

The study, conducted by the University of Plymouth and Blue Marine Foundation, has been published in the journal Marine Ecology, and is the first to demonstrate the increased ecological importance of shipwrecks – and the areas surrounding them – in areas of heavy fishing pressure.

Jenny Hickman, the study’s lead author, completed the research as part of her MSc Marine Conservation programme at the University of Plymouth. Jenny said: “The industrial use of bottom towed fishing gear has been commonplace since the 1800s, and has significantly altered marine communities and ecosystem services. Outside of legal protection, only areas inaccessible to trawlers are offered any protection, which is why shipwreck sites are rarely subject to trawling pressure. As many have been in situ for more than 100 years, they offer a baseline of ecological potential when trawling pressure is reduced or removed.”

The research was conducted around five shipwrecks off the Berwickshire coast, which are all thought to have sunk in the late 19th and early 20th centuries. The research teams, supported by local boat crews, gathered video footage of the shipwrecks, the surrounding 50m radius, and control locations more than 150m from the wreck site.

Researchers say the latest study demonstrates the importance of factoring wreck sites into future conservation plans, but also the benefits of Marine Protected Areas (MPAs) status.

The full research paper in Marine Ecology can be read here.