Kittiwakes are among birds said to be having breeding problems
The poor breeding of Scotland's seabirds is giving cause for "serious concern", according to RSPB Scotland.
Early reports from coastal reserves indicate continuing problems for the internationally important populations of guillemots, kittiwakes and others.
Nests have been abandoned, with cliffs which "should be teeming" now empty.
RSPB Scotland has called on the Scottish Government to ensure that it puts the environment at the heart of new legislation.
Speaking ahead of the launch of the Marine Bill Consultation on Monday, the bird conservation group said evidence suggested these repeated annual breeding failures are now substantially reducing populations of certain species.
Colonies on the Northern Isles of Orkney and Shetland - together said to be Scotland's most important "seabird cities" - have been hit particularly hard.
Many guillemots and razorbills appeared to have given up any attempt to breed at RSPB's Sumburgh Head reserve on Shetland, with eggs left abandoned on the cliffs as parent birds spent more time at sea in a search for food.
Kittiwakes also had serious problems.
RSPB Scotland said that on the Aberdeenshire coast, at Fowlsheugh, the picture was more encouraging, with razorbills, guillemots and kittiwakes appearing to be nesting successfully, although counts were still down on historic numbers.
On the west coast, the breeding season was said to have been more mixed, with both razorbills and kittiwakes experiencing a poor year, but some Arctic tern colonies had fared well and were bringing in plentiful food supplies.
Doug Gilbert, an ecologist with RSPB Scotland, said: "Regrettably the poor breeding performance of our internationally important seabird colonies is now an annual theme.
"When you look at the evidence over the last 15 years it is quite startling and cause for serious concern.
Some Arctic tern colonies were said to have fared well
"At our Copinsay reserve on Orkney, the kittiwake population has plummeted drastically since the mid 1980s, when there were at least 10,000 birds on the cliffs, but today there are just under 2,000."
He added: "The declines are primarily being driven by changes in the availability of the fish that these birds depend on.
"Seabirds are indicators of the health of the marine environment and, like the canary in the coalmine, the decline in their fortunes should be a wake-up call to us all that we must pay attention to."
RSPB Scotland is calling for the Scottish Government to put the environment at the heart of the Marine Bill to help improve the fortunes of seabirds.
Kara Brydson, marine policy officer with RSPB Scotland, said: "The Scottish Marine Bill will not be a silver bullet that will suddenly mean that the problems facing seabirds will be solved overnight.
"But it should represent a policy shift that means putting environment at the heart of decision-making and having proper sustainable management of the seas rather than treating them as something that is available to be exploited and used with impunity."