The Department of Fisheries and Oceans is searching for an emaciated humpback whale spotted somewhere in Cowichan Bay.

The DFO says it has received a number of reports on the sick-looking whale and is now trying to track it down for inspection.

An unconfirmed report circulating on Facebook says the whale drifted into the bay on Sunday, and that a diver who inspected it couldn't find a major injury or net entanglement.

The post called for boaters to maintain a respectful 100 metre distance from the whale to either protect it while it heals, or to let it die in peace.