Tourists and locals who moor their luxury yachts in Studland Bay, Dorset, are threatening the UK's largest colony of seahorses, warn conservationists.
Seahorses became a protected species in Britain in April, but boats anchoring off shore in Studland are destroying the eel grass they live in.
Marine photographer Steve Trewhella has been monitoring their population for the Seahorse Trust.
He told the Guardian: "Imagine a 50kg anchor in a six-feet depth of water and times that by hundreds of boats. Natural England said they only conserve against intentional damage - it's a get out clause."
Neil Garrick-Maidment, director and founder of the Seahorst Trust, also suggested the wording of the Wildlife and Countryside Act protecting the species isn't clear enough.
He told the Guardian: "It's a site of international importance. The Act says both the seahorse and its habitat are protected, but if you aren't aware that the moorings off the beach are illegal then you can say you didn't know.
"We're not trying to be killjoys, we're just saying be careful where you put your anchors- don't put them in the eel grass."
"Their eel-grass habitat has been fragmented by boat anchors and heavy mooring chains. Last Saturday there were 173 boats in the shallow part of the bay," he said.
"The owners get close to the beach because they want to show off and be seen on their boats.
"We have had experienced divers spend many hours looking for seahorses this year and they haven't found any. They have disappeared and this is absolutely disastrous."
He suggested that the areas should be made a Marine Protected Zone, meaning that buoys would be placed for boats to use instead of them dropping anchor.
View more amazing ocean wildlife below: