Poole Harbour already attracts ospreys, but they don't nest there
The RSPB is hoping to encourage ospreys at two sites in Dorset to nest - by installing plastic models of the birds.
The wildlife charity hopes the fake birds, in manmade nests, will help persuade real ospreys the area is a good place to mate and nest.
Arne nature reserve and Poole Harbour are regularly visited by ospreys in the spring, as they return from their winter location, south of the Sahara.
Both sites are important spots for ospreys, but few breed there.
The RSPB hopes to establish ospreys as a 'flagship species' for both Arne and Poole Harbour.
Mark Singleton, RSPB Arne Visitor Manager, said: "This is a really exciting experiment and one that has worked at other locations in Europe, so we're hopeful that before long we might just have some breeding ospreys of our own.
"We have an osprey expert, author and broadcaster Roy Dennis, with us, and ideal flora and fauna and hunting grounds nearby.
The RSPB say the project could last around five years
"So with all the right elements in place all we can do now is keep our fingers crossed."
Longer term project
Mark, based at Arne, has been busy putting the first of the plastic birds into place.
He said: "So far, they're looking amazing, but we won't get any breeding birds this year - it's a longer term project, perhaps over five years or so.
"We get lots of ospreys but they only use it as stopping off point. We want them to stay longer, especially the younger ones, so they can go on to breed.
"If we did get ospreys breeding at Arne it would be an amazing conservation success story and as well as improving the population and range of this magnificent bird a little more, I think it would be fantastic for our visitors."
Ospreys were once an extinct species in Britain, but returned to breed in the 1950s.
As well as the plastic life size birds, five artificial osprey nests (known as 'eyries') will also be put in place.
They will be placed in trees at Arne, and two will also be placed at a site in Poole Harbour.