By PHILIP ENGLISH
The rare Cook's scurvy grass has a better chance of survival in the Auckland region, thanks to a new find.
Until last week it was thought there were no more than about 50 of the plants in the wild. But a survey by Department of Conservation staff of
islands near Great Barrier has found more than 1000 plants on Mahuki Island.
Captain James Cook encountered the plant, also known as coastal cress, in the Bay of Plenty on his first voyage to New Zealand in HMS Endeavour in 1769.
As a pioneer in battling scurvy or vitamin C deficiency among sailors, Cook recognised the plant as a member of the cabbage family and realised its potential to ward off the disease.
Cook's scurvy grass, Lepidium oleraceum, is now almost extinct on the North Island mainland, but about 400 plants grow on a few islands.
DoC botanist Bec Stanley said the future looked brighter for the plant now there were at least 1500 specimens in the North Island. The South Island had a population of about 5000.
She said the plant was usually associated with seabirds which nested in burrows in areas where guano was abundant.
"It thrives in this high-nutrient environment with heaps of nitrogen and heaps of phosphorus."
She said that as colonies of birds such as gannets and petrels had declined because of the introduction of predators such as rats, stoats, cats, dogs and hedgehogs, Cooks scurvy grass also declined.
The survey also found a small grove of the endangered milk tree, or turepo, on an unnamed island, and extremely rare native cucumber vines on Okokewa Island.
