Coastguards were called out after a passer-by found an upturned dinghy.
Members of Wyke Coastguard Rescue were sent to the scene at Osmington Mills yesterday morning.
A spokesman for the team said: "On arrival it was clear that this 14ft dingy had washed ashore after been blown from a hard standing or breaking its moorings, quite possibly in Portland Harbour.
"With no signs of recent occupancy we were stood down."
Anyone with knowledge of the dingy, named 'Halma', is being urged to contact coastguards.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here