Lyme Bay is a marine biodiversity hotspot of national conservation importance. It has reefs covered in corals, maybe not as colourful as a tropical reef, but with the largest colony of pink sea fans in the country, and other rare corals like the bright-yellow sunset cup coral and more than 300 species.

Lyme Bay extends from Portland Bill in Dorset to Start Point in Devon. A smaller area became the Lyme Bay Marine Protected Area (MPA) in 2008 to preserve the rare corals and sponges that grow on the rocky reefs between West Bay in Dorset and Beer in East Devon.

Local fishing boats have adopted a voluntary code of conduct that restricts the number of pots and nets used in the reserve. And Lyme Bay Reserve was the first Marine Protected Area in the UK where bottom-trawling and dredging were banned, over an area of 90 square nautical miles.

Before the ban, large boats dredged the Jurassic Coast for scallop. Heavy metal-toothed rakes were towed along the seabed, ripping up anything living and growing in their path, turning the reefs into rubble.

Bottom trawling involves dragging weighted nets along the seabed. Delicate habitats and plants that take years to establish are wiped out in an instant. Many parts of the seabed are exposed to at least one pass of a trawl every year. Such methods are indiscriminate, catching and killing non-target species.

The University of Plymouth has monitored Lyme Bay MPA since the banning of bottom trawling and dredging in 2008, and over 20 scientific papers have been published on the recovery of Lyme Bay Reserve.

Species that rely on the reef have increased by 95% and the abundance of fish has grown by almost 400%. The pink sea fans that grow 1 cm a year and live to 50 years old are slowly recovering. Common dolphins, sunfish and bluefin tuna visit the waters, and basking sharks during summer.

However, fish like bass, cuttlefish and rays have not recovered as they are mobile and continue to be overfished outside the reserve. Conservationists are calling for a no-trawl and no-dredging zone right across the mouth of the bay from Portland Bill to Start Point to allow these fish to recover.

A staggering 74% of England’s inshore Marine Protected Areas still permit bottom trawling and dredging. This also contributes to climate change as when the seabed is dredged, huge quantities of stored carbon are released into the atmosphere. Off the Cornish coast, the Southwest Deeps (East) MPA stores an estimated 1.67 megatons of carbon, the equivalent to over 1 million return flights from London to Sydney, yet it still has no formal protection from bottom trawling.

The previous Conservative government set a target to restrict harmful fishing practices like bottom trawling and dredging in all the 181 MPAs that cover 40% of England’s waters by the end of 2024. This deadline has now passed, and it is time for the present government to set out how they will protect our MPAs.