New Zealand’s rare woollyhead rises again with 250 new seedlings
New Zealand’s rare dryland plant was running out of chances to survive What began with hopes for 20 plants soon produced hundreds of seedlings For
New Zealand’s rare dryland plant was running out of chances to survive What began with hopes for 20 plants soon produced hundreds of seedlings For conservationists, keeping hundreds of seedlings alive was the next challenge About 250 seedlings are now back in the reserve The woollyhead has numbers again, but survival is far from guaranteed From the brink of extinction, 250 seedlings are getting a chance to survive On the dry plains of Central Otago, a small native herb has been given another chance to survive in the wild. Craspedia argentea, a woollyhead found only around the Pisa Flats, had dwindled to just two known plants. By then, even the ordinary business of pollination had become difficult. There were simply too few plants left for the population to function as it once had. Conservationists stepped in, collecting the tiny amount of seed they could find and beginning a careful programme of hand-pollination and propagation. According to Radio New Zealand (RNZ), two years of work at Dunedin Botanic Garden have now produced hundreds of young plants. About 250 seedlings are being returned to Mahaka Katia Scientific Reserve, where their next challenge will be surviving without the protection of a nursery.Craspedia argentea belongs to the dryland flora of Central Otago, a region known for its sparse vegetation, harsh conditions and wide open landscapes. The plant is endemic to the Pisa Flats, meaning its natural range is confined to this particular part of New Zealand.That makes the loss of a local population especially serious. There is no second wild population elsewhere in the country waiting to replenish it.Botanist Geoffrey Rogers has spent much of his career studying the plants of Otago’s drylands.
He had seen Craspedia argentea become increasingly scarce, despite the protection offered by the reserve.The problem was not simply a matter of fewer plants appearing each season. As the population shrank, the pollination system that helped the plants reproduce also began to break down. Then came an alarming indication of just how little remained.As reported by Radio New Zealand (RNZ), in one season, conservationists were able to collect only three seeds. Two germinated. Those two plants became the foundation of the recovery effort.For Richard Ewans, a senior technical adviser in ecology with New Zealand’s Department of Conservation, waiting for the species to recover naturally was no longer a realistic option.Richard said, "We've been really concerned about this plant disappearing.... so we knew we had to intervene and start a programme of breeding."The conservation team began a breeding programme, with the aim of producing enough plants to eventually put back into the reserve. It was delicate work. Flowers had to be pollinated by hand, seeds collected and seedlings raised under controlled conditions. The Dunedin Botanic Garden became an important part of that process, with staff spending about two years working out how to produce healthy plants in useful numbers.At first, the expectations were modest. The team thought it might eventually have 20 or 30 plants ready to move back into the wild. Instead, the propagation effort produced far more. About 800 seeds were obtained in the first season, and those seeds produced roughly 300 seedlings. For a plant whose wild population had once been reduced to two known individuals, the change was substantial.Getting seeds to germinate was only the beginning.
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