The UK government has added 12,000 square kilometers (approximately 4,633 square miles) to England's "blue belt" of protected marine areas, meaning the UK now protects a swath of its ocean nearly twice the size of England itself, The Guardian reported Friday.

The 41 new Marine Conservation Zones were created by Environment Secretary Michael Gove Friday and cover an area off the coast of England that is nearly eight times the size of greater London, according to a government press release.

"The UK is already leading the rest of the world by protecting over 30 percent of our ocean — but we know there is more to do. Establishing this latest round of Marine Conservation Zones in this Year of Green Action is another big step in the right direction, extending our blue belt to safeguard precious and diverse sea life for future generations to come," Gove said.

The new zones range from the waters around the Isles of Scilly in the south to the Northumberland coast in the north, The Independent reported. They will protect species like rare stalked jellyfish, short-snouted seahorses, eider ducks, basking sharks and ocean quahog and habitats including ross worm reefs and blue mussel beds.

The Wildlife Trusts celebrated the occasion with a Twitter thread on the history of marine protections in the UK. In the 1980s, the group said, there were only three Marine Nature Reserves in the waters surrounding the country.

"During this time, horse mussel communities were destroyed in one of the few marine nature reserves we had. There was an epidemic of seal deaths in the North Sea. We knew we needed a new approach," the group wrote.

In 2002, the group agitated for a bill that would better facilitate the protection of the UK's marine environment. They sent 250,000 signatures to Westminster, the seat of the UK Parliament, in a "Petition Fish" to promote the bill.

Finally, in 2009, the government passed the Marine and Coastal Access Act, which empowered it to designate and manage protected areas.

Since 2013, the government has designated 91 Marine Conservation Zones off the English coast in three waves, bringing the UK's total number of all kinds of protected areas up to 355, The Independent reported.

Director of Living Seas at The Wildlife Trusts Joan Edwards called Friday's announcement "fantastic news."

"Now we need to see good management of these special places to stop damaging activities such as beam-trawling or dredging for scallops and langoustines which harm fragile marine wildlife," Edwards said in the government press release.

There is, however, debate about how effective the UK government's efforts have been when it comes to actually protecting marine life.

"These areas are poorly monitored and we have little evidence that wildlife is benefiting," WWF Head of Marine Policy Alec Taylor said, as The Independent reported. "We need proper management of activities within the boundaries of all marine protected areas and strict enforcement of safeguarding laws. Only then can we secure a future where people and nature thrive."

But Edwards told The Guardian that the protected areas had made a real difference.

"They are not paper parks. Many of the sites here in Devon have had scallop dredging banned so the most damaging activities have been stopped," she said. "The pressure of fishing has been removed from a very large part of our seabed which is good for nature conservation, and good for fishermen because if you have areas that are left alone they will produce more fish."