Plans to charge a £100 annual fee to use small boats in the Firth of Clyde have prompted a backlash from owners, leisure groups and local politicians.

Harbour authority Peel Ports Clydeport is proposing a "leisure vehicle conservancy fee" for boats between 6m and 24m in length.

The firm, which has jurisdiction over 450 square miles of the river and nearby waters, said the charge would help cover the cost of managing leisure activity and dealing with accidents.

But small boat owners have told BBC Scotland News the plan could harm leisure tourism and penalise traditional activities like fishing across a huge area.

The charging zone could stretch from Albert Bridge in Glasgow as far as the island of Arran, and include sea lochs such as Loch Fyne and Gare Loch.

Conservancy fees are often charged by harbours to cover the cost of services and upkeep but are usually applied to larger commercial vessels and based on gross tonnage.

In the east of the country, Forth Ports provides an exemption for leisure craft in the Firth of Forth and on the Tay, while Argyll & Bute Council takes a similar approach around Oban.

But Peel Ports is already levying fees for small boat owners at another port it owns, at Medway in Kent, and says it is in the "early stages" of introducing charges for the Clyde from this year.

A consultation document suggests a £100 + VAT annual fee for boats regularly sailing in the Clydeport area, a £75 fee for summer-only use and a daily charge for visiting craft.

Peel Ports said there has been a rise in vessels adrift or sunken in waters controlled by the company, as well as an increase in recovery costs.

A spokesperson added: "The funds will help cover the rising costs of managing leisure vessel activity, such as the survey, marking and recovery of abandoned vessels, maintaining navigational aids, and supporting around 450 annual leisure events within the jurisdiction.

"We will be holding a formal consultation, during which all marine users will be given the opportunity to share their views."

Members of the Port Glasgow Boating Club, a small member-run group in Inverclyde, are among those opposing the fee plan.

Some told BBC Scotland News they felt frustrated with the lack of clarity from Peel Ports.

They said they have not had an opportunity to discuss the matter, and they described the fee as "extortion" of the leisure boating community.

One club member, Craig Scholte, an offshore worker, said the fee would make recreational boating unaffordable for older people who rely on it as a social outlet.

He said: "I don't see a purpose [for the fee] that's going to help me out sailing on the Clyde. I'm not getting anything different now than I'll be getting paying another £75-£100 per year.

"If my boat broke its moorings, a squad of us from the club would go out and recover it, I wouldn't rely on Peel Ports for that. It's not a reasonable fee."

Many members of the club are retired men who once worked on the Clyde, some in the nearby Fergusons shipyard.

Several of them meet daily at a small hut in the boatyard to socialise and share a cup of tea, even when they are not using their boats.

Ian Clark said the fee poses challenges to retired boat owners who are on a fixed income.

He said: "I've got to think whether I can afford it. It just means it makes the difference between living comfortably and watching every penny that you spend.

"Peel Ports behaviour in this has been outrageous because they've taken money in the form of grants and they've given back to the community nothing.

"There's no involvement in local activities, there's no consultation. I'm really quite outraged when I look at the profits they've made, hundreds of thousands a year, and what do they do for it? They do nothing for us. Really nothing."