Tiny seedling gives hope for survival

By BRIDGET CARTER

A tiny seedling found on a remote treasure island at the tip of New Zealand gives scientists hope that they can keep alive what is thought to be the world's rarest tree.

Great Island's small, tropical-looking Pennantia baylisiana tree is in the Guinness Book of Records because it is the only one alive.

Now, for the first time in almost 60 years, scientists have found a pennantia seedling on the island, 64km north of Cape Reinga. It suggests the plant breed could be on a comeback.

Plant experts discovered the seedling during a 10-year follow-up by Landcare Research and the Department of Conservation as part of the decades-long project to protect plant life on Great Island.

DoC botanist Lisa Forester said the seedling sprang from fruit that scientists had planted as seeds around the rest of the island from the stand-alone pennantia.

Of two seedlings that sprouted, one died, but the other could help to revive the species.

"This is the best result we have seen so far," Ms Forester said.

The pennantia tree is one of a dozen plants that grow exclusively on Great Island, described by scientists as "the jewel in the crown" of New Zealand's nature reserves.

The 350ha island, the largest of the Three Kings group, is also famous for shipwrecks and lost treasure - divers recovered thousands of gold coins from the Elingamite, a passenger steamer wrecked there in 1902.

According to Landcare Research plant scientist Peter Bellingham, moves to protect the island's plant life started in the late 1940s after ecologically destructive goats, which were introduced to the island as food for shipwreck survivors, were shot.

Ms Forester said Three Kings Islands were unique because their isolation from the mainland for hundreds of thousands of years had allowed their unusual tropical-looking plants to evolve.

Landcare plant pathologist Ross Beever said the pennantia seedling was probably female, like the tree. Chances of regeneration on the island would be greater if it were a male plant.

Ms Forester said pennantia plants were grown domestically in New Zealand in a scheme aimed at keeping the species alive.

But scientists were reluctant to take mainland plants to the island for fear of introducing fungi.

Instead, scientists would wait 10 years to see if a pennantia revival was underway. If not, there would be more intervention to ensure the species' survival.