The RSPB manages more than 300 man-made islands at its wetland reserves.
Islands provide nesting, roosting and loafing sites secure from land-based predators, and many bird species will choose them in preference to mainland locations with similar habitat features. Islands are also created to concentrate birds in front of hides to provide visitors to reserves with good views without disturbing the birds.
The species found on islands will vary depending on the habitat and location of the water body. Avocets and little terns are mainly found in the south, and they prefer sparsely vegetated islands, while red-throated divers, goosanders and red-breasted mergansers will be found mainly in the north and choose tall and dense vegetation.
Several small islands in a water body are more valuable to a breeding colony than one large one.
These pages provide information on the design, siting, construction and maintenance of man-made islands.