Keep Scotland Beautiful, the Marine Conservation Society and The Scottish Seabird Centre have come together as part of a campaign to rid the coastline of litter which kills seabirds as well as dolphins, seals and turtles.
They want people who litter on Scotland's beaches, including in Inverclyde and Ayrshire, to think about the dangers.
Plastic and polystyrene can be broken down into small bits in the sea - these can then be ingested by birds resulting in death. Plastic bags can cause animals to become tangled and can be mistaken for jellyfish and other food by dolphins and turtles.
Derek Robertson, Chief Executive of Keep Scotland Beautiful, said: "A beach user leaving the empty strawberry carton, or a ferry passenger throwing a bottle overboard, or someone discarding a plastic bag, can be responsible for the death and distress of seabirds and marine wildlife.
"The Clean Up Scotland campaign is aimed at making people understand the consequences of their actions.
"There are almost 1700 items of litter on every kilometre of Scotland's coastline. That is a statistic which we hope will shock everyone who drops litter to change their behaviour."