An underwater search is seeking to discover important plants lurking beneath the surface of England's largest natural lake.
The area is popular with tourists to the Lake District
Windermere is home to a wide variety of aquatic vegetation, such as the white water lily and water lobelias.
Information on their location will be used when planning applications are made for developments on the lakeshore, or for boat moorings.
Research will involve five days of diving into the 67m (220ft) deep lake.
The Lake District National Park Authority (LDNPA) has joined forces with South Lakeland District Council's Windermere Management Strategy for the project.
Carrisa Lough, from the LDNPA said: "Windermere has a wide variety of aquatic macrophyte species, including the white water lily and water lobelia.
"We need to know where these plant beds are so that we can protect them.
"They are important sources of food for fish, so conserving them helps fish populations as well. They also provide habitat for other species.
"We will share the findings with other interested organisations such as the Still Waters Partnership, English Nature, the Environment Agency and Cumbria Wildlife Trust."