Donald Trump's golf course plans and a possible wind farm nearby could badly harm coastal wildlife, RSPB Scotland has warned.
Mr Trump visited the sand dunes where the course will be located
US billionaire Mr Trump hopes to build the world's best golf course in Aberdeenshire.
There are also unrelated plans for a major wind farm off the Aberdeen coast.
The RSPB has expressed concern over the impact of the developments. The Trump Organisation said it was in discussion with Scottish Natural Heritage.
RSPB Scotland director for east Scotland, Dr Martin Auld, said: "There is a lot at stake. The environmental impacts need to be looked at very carefully."
The organisation has said it was "extremely concerned" the two large-scale developments on the coast could have the potential to harm the area's internationally important wildlife.
The wildlife charity is urging local councillors, planners, industry representatives and other stakeholders to consider the wildlife value of the area before progressing their plans.
Dr Auld said: "These developments are being talked about as if consent has already been given, but there is a lot at stake.
"We have voiced our concerns about the potential impacts of a wind farm in Aberdeen bay to the developers and are waiting to see what they are now proposing."
The water off the Aberdeenshire coast plays host to thousands of birds, including geese, and the sand dunes are also seen as environmentally important.
Last month Mr Trump visited the proposed site of his £300m dream, at the Menie Estate, and expressed concern about the wind farm.
"I am not thrilled - I want to see the ocean, I do not want to see windmills," he said.
The RSPB said geese were among the birds at risk
His plans include two championship courses, a hotel and holiday homes.
The development could bring £150m to the local economy over the next decade and create 400 jobs.
A spokesperson for The Trump Organisation said: "Mr Trump has stated on many occasions that he is very keen to work with environmental bodies and to follow all correct procedures when developing his golf course as he always does.
"The Trump Organisation and its environmental consultants are already in talks with Scottish Natural Heritage and have been for some time. These discussions will continue throughout the course of the development.
"The Trump Organization is currently working on the planning application for Trump International Golf Links and is in consultation with all relevant environmental bodies, specialists and consultants.
"We very much respect the planning process and the procedures involved."
The group behind the plan for the wind farm has said objections from Mr Trump have had nothing to do with a change to the scheme, which was unveiled on Wednesday.
The original plan envisaged a string of 33 giant turbines standing in the sea in a line.
Aberdeen Renewable Energy Group (AREG) has modified the proposals, now with 23 turbines in a more compact grid design several miles south of Mr Trump's proposed development, and is due to hold more public consultations.
An AREG spokesperson said: "The latest layout reflects the progress made in discussions with key stakeholders.
"It leaves a framework for us to work towards a final design which we hope to send with our planning application to the Scottish Executive early next year."