It was probably one of the most unusual farewells at an airport.

After swimming more than 700 miles, swept into the unknown on ocean currents, a stranded Atlantic Harbour Seal was finally on his way home.

The young male, who first washed up on our shores six weeks ago, was airlifted back to the north-eastern seaboard to start the next chapter of his amazing story.

After five-and-a-half weeks recuperating from near-starvation and a deep cut to his neck, the seal left his quarantine pool at 6.10 p.m. on Tuesday to board his flight to the US.

Loaded into a 3ft by 6ft wooden crate constructed by BAMZ plant staff, the seal was taken to L.F. Wade International Airport by FedEx, which had picked him up in a van, with BAMZ head aquarist Patrick Talbot accompanying him in the back.

I followed with BAMZ acting principal curator Dr. Ian Walker, animal registrar Barbara Outerbridge and Dr. Brent Whitaker, a veterinarian from the National Aquarium in Baltimore.

As we approached the Causeway, Dr. Walker stopped the car at the Shell Station to buy two 10lb bags of ice cubes. I was intrigued, and so apparently was the cashier at the gas station.

Tuesday marked the coldest March 24 since 1967, and she told him: "That's the only ice we've sold all day. It must be a special occasion."

"Yes, I'm FedExing a seal," he replied.

"Well that's cool," she said.

And so apparently, the seal would be on his one-and-a-half hour flight. The ice cubes were a necessity for him to chew on if he got too warm or thirsty onboard. It was not allowed any food or drink on the flight as it could make him sick.

On arrival at the airport, we watched as the seal was loaded on to the 727-200 Cargojet cargo plane. It had taken an army of people and extensive teamwork to get him back to East Coast, and he still has some way to go, with further rehabilitation at the National Aquarium in Baltimore before being re-released into the wild.

Ms Outerbridge alone has had a mountain of paperwork and US security clearances to arrange. This has included: a special Bermuda Government permit to export a marine mammal; a NOAA National Marine Fisheries Service permit allowing him to be imported to the US for medical reasons prior to release; letters from Dr. Walker and Dr. Whitaker requesting his importation and stating fitness to travel; and a US Fish and Wildlife Service (FWS) importation permit.

The seal even had his own US FWS officer awaiting to inspect him at Customs on arrival at Newark.

At 7.15 p.m. the cargo plane took off but as we came to leave however, the car battery failed. Ms Outerbridge called her husband, a dentist, to come out and jump start us.

"I guess you can see the irony of this," said Mr. Talbot. "The animal is signed, sealed and delivered and now we're the ones stranded, awaiting the arrival of a doctor."