Lakeside dog walkers have been warned to keep pets on a lead to protect nesting mute swans and mandarin ducks.

Both species have been identified as nesting in Rickmansworth Aquadrome, prompting the calls from Three Rivers District Council for greater care until June 1.

Council biodiversity officer Jess Hodges explained that if people or dogs get too close to a nesting bird it could “panic, get stressed, and even abandon the nest along with its eggs or young”.

“If you see a bird on the ground and it doesn’t move away as you might expect, don’t get too close and give it some space as it may be sitting on a nest,” she added.

The nature reserve’s two lakes, at the northern end of the Colne Valley Regional Park, are home to a large variety of birds which also includes herons and moorhens.

The council added that close control of dogs while walking along the lakeside this spring “will give the birds the best chance to raise their young”.

Jess added: “Many birds can be protective of their nests and eggs as they try to keep their young safe.

“It is very important for both people and dogs to not get too close.”