As the impacts of climate change and other threats mount, conservationists are racing to preserve endangered plant species in botanical garden "metacollections" in the hope of eventually returning them to the wild. But what happens when there is no suitable habitat to return them to?
In the spring of 1994, David Noble rappelled down the sheer cliff of a narrow canyon, part of a tangled maze of escarpments deeply incised into the sandstone tablelands in Australia's Wollemi National Park, some 90 miles northwest of Sydney. There, the off-duty National Parks and Wildlife Service officer stumbled upon a strange group of towering trees with distinctive bubbly brown bark and deep green needles and cones. Later called the Wollemi pine, Wollemia nobilis, the species is a member of the ancient Araucariaceae family of conifers and had been presumed extinct for 70-90 million years. It was the equivalent of discovering a Tyrannosaurus still alive on Earth. Like other scientists working on the knife edge of emergency botany to save critically imperiled plants, Australian conservationists rushed to protect the Wollemi pine within its native habitat, an approach known as in situ conservation. There, a single population of just 45 mature individuals and 46 juveniles survive in the moist rainforest that occurs in deep gorges that have, for eons, been sheltered from wildfires that regularly ravage the dry vegetation atop the plateaus. The critically endangered conifer was an instant target for plant thieves, so the exact location of the trees is a closely guarded secret. "We're literally right now deciding which species survive into the future and which do not," says a plant conservationist. Researchers also began employing ex situ conservation, in which endangered plants are propagated outside of their natural habitats, under the assumption that the new plants will eventually be returned to the wild to bolster dwindling native populations. A backup collection of propagated Wollemi pines was created at Australian Botanic Garden Mount Annan, in a suburb southwest of Sydney, as an insurance policy against extinction. What's more, because so few individuals remain in the wild and all of them are in a single area, newly propagated trees have been translocated to…
Janet Marinelli, Anita Makri, Jim Robbins, Omnia Saed, Fred Pearce