The three-metre lateral marker was spotted south of the island by Condor Rapide yesterday morning.
Despite “very challenging conditions”, French Customs boat Pleuville Le Pelley was able to bring the green buoy back to St. Helier Harbour.
The Jersey Coastguard then used its work boat to help haul it in.
After the ‘rescue’, Jersey Coastguard commented: “Jersey Coastguard would like to offer our thanks to the French Customs for their assistance today.”