SHIRAHAMA, Japan >> Giant pandas’ all-you-can-eat bamboo buffet is so plentiful that uneaten bamboo is being used to create spawning reefs for squid, which are declining in number. The effort aims to boost catches in Wakayama prefecture.

The bamboo comes from a zoo in the Adventure World theme park, with park staff building 30 sections of artificial reef using the excess bamboo. The project, which launched in May, centers in waters off three fishing ports in Shirahama, where aoriika squid spawn.

Bamboo is the staple food of pandas. The zoo procures the evergreen plant for its seven pandas from a bamboo grove in Kishiwada, where residents were concerned about environmental damage due to overgrowth.

Pandas eat some 44 to 66 pounds of bamboo each day, but because they prefer leaves, many parts of the plant go uneaten. To avoid wasting the leftovers, zoo staff previously crafted lanterns and tumblers. In their search for other ways to use bamboo stalks, they learned about the dwindling squid catches, caused by a recent change in direction of the Kuroshio current — which brings warm seawater to Japan’s southern coast — and hit upon the idea of making artificial reefs.

Reefs are created by inserting the stalks into holes in concrete blocks, which are then placed on the sea floor more than 200 yards from shore, at a depth of about 23 feet. Divers use sandbags to secure the reefs.

The reefs’ effectiveness will be monitored through the end of the hatching season, then removed to maintain the marine environment.

“Squid were quick to lay eggs on a trial reef we set up,” said a zoo staffer. “We hope the bamboo reefs will help restore the sea’s richness.”

The project will be repeated next year if squid numbers improve. The zoo now plans to build bamboo reefs for other marine species.