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.
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Wednesday morning's weather for the east of the region
Wednesday morning's weather for the west of the region
Detectives investigating the death of Eastbourne woman Emma Crowhurst have released the first available photograph of her.