A passing tug saw the mammal, a young female humpback measuring around 36ft (11 metres) long, off the Isle of Sheppey in Kent.
Local navigation warnings were issued to vessels in the area to be aware of the floating carcass before it was towed to Sheerness Docks, Thames Coastguard said.
More top news
Friday night's forecast for the west of the region
Friday night's forecast for the east of the region
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