It was a staggering mission to make the love story of two of Ocean Park's largest animals come true. It took 15 months of careful planning and complex logistics to bring Rock - weighing 767kg, or as heavy as 12 average human adults - and 14-year-old Miru (574kg) from two aquariums in Japan to Hong Kong.
Miru lost her home in Fukushima in the 2011 earthquake and tsunami. According to Philip Wong Wing-hong, Ocean Park's curator of polar animals, the bottom two floors of the aquarium where Miru lived were flooded, and the power supply and water circulation system were damaged. Worse, her "boyfriend" died from a disease afterwards, so the aquarium had to find her another home.
Ocean Park, which has close relations with aquariums and zoos worldwide, happened to be looking for animals for their Polar Adventure and decided to take Miru in. At the same time, they got wind that captive-bred Rock, living in the Kamogawa Sea World near Tokyo, needed a new place. The park thought they would make a nice breeding pair.
Ocean Park officials meet Japanese colleagues
Ocean Park sent a handful of vets and animal trainers to Japan several times to get to know the walruses and learn about their daily care. They stayed up to a month on every visit.
When Miru made the 13-hour road trip from Fukushima to Kamogawa in January 2012, the Hong Kong team monitored her health and sprinkled her with water in an air-conditioned truck. "Fin-footed mammals such as walruses and seals can stay out of water for a while as long as you keep their skin moist," Wong says.
The truck that transported Miru in Japan
Their journey to Hong Kong was a lot more trouble. Even though Ocean Park had imported many animals before, the larger the animal, the more difficult it is to move it, explains Wong.
Miru took a four-hour chartered cargo flight last June. The pilot was instructed to keep the cabin temperature at about 14 to 15 degrees Celsius. Air pressure had to be maintained at a special level for the animal's comfort. "We wanted the last leg of Miru's journey to be short and safe," Wong explains.
The park also had to design a special metal travelling enclosure for her. The three-metre-long cage was spacious enough for her to lie comfortably. Trainers placed the cage in her Kamogawa home to let her get used to it. The idea was to keep her unstressed during the trip, says Wong.
Miru was served her regular plate of clams, squid and capelin hours before the flight, Wong says, so that she would not have a full stomach and vomit if she felt unwell. Also, she wasn't sedated for the journey. "If she were sleeping, the vets would not know if she was in any discomfort," Wong says.
The cargo jet that flew her to Hong Kong
A team of about six vets and animal keepers both from Japan and Hong Kong watched over her all the way. Even more were waiting for her at the airport. Cranes were used to move her cage to the truck.
On the way to Aberdeen, the driver had to go no faster than 80 km/h even though some highways allow a speed of up to 100km/h. "We didn't want Miru to get truck-sick," Wong says.
Rock met his partner in October. They started dining and receiving their daily training together in February. The next step is arranging for the two to spend more time alone.