Threatened orchids are being reintroduced to sanctuaries on private land
The Tawny Spider-orchid, Caladenia fulva, is one of the endangered spider-orchids being reintroduced on private land. Image: Noushka Reiter.
Somewhere in the bush in Victoria, protected by a fence, a population of orchids is growing. We can’t tell you where. We can’t even tell you exactly what species they are. But orchids like these are providing hope for one of the most threatened groups of plants.
Orchids are so entrancing that to protect the most endangered species, their identity and location must be kept secret. Apart from trampling by well-meaning orchid-lovers, poaching is a real problem. In 2023, hundreds of rare orchids cultivated at Kings Park in Perth were stolen, likely for the black market.
What is it about orchids that drives people so wild?
“They’re bright and eye-catching, even though our orchids are quite small. Their flowers are intricate and exquisite,” says Ben Cullen, Trust for Nature’s South Central Area Manager. “They’re also cryptic. They might only flower for a day once a year. Or they might appear once in 20 years and then disappear.”
With over 35,000 species worldwide, orchids are one of the most diverse groups of plants. Most of the 400 species of Victorian orchids are ground-dwellers: they grow from a tuber in the soil where they form lifelong relationships with specific fungi, and disappear below the surface when they’ve finished flowering. Although orchids can be found year-round, late winter and spring are the best times to find them.
Orchid flowers grow in an astonishing variety of form and colour, from the brilliant blue and purple of sun orchids, the bright yellow, orange and pink of donkey orchids, and the subtle green, brown and white of greenhoods and leek orchids. People have seen all sorts of animals in their shapes: spiders, mantises, flying ducks, golden moths and gnats.
Many of these peculiar forms have evolved to attract, and even deceive, specific pollinators. Spider-orchids, for instance, imitate female wasps to trick males into attempting to mate with them, even producing chemicals that mimic insect pheromones to heighten the illusion.
“Through their relationships with fungi and pollinators they offer a direct connection through to an ecosystem and its health. With all the threats we’ve introduced to landscapes these guys are highly prone to extinction,” says Ben.
As serious a threat as poaching poses, loss and degradation of habitat is critical. Although some species are still common, many others have declined precipitously. For some species, only a few dozen plants still exist in the wild, and are now found in tiny areas of remnant habitat.
Pink Spider-orchids grown at the Royal Botanic Gardens Victoria. Image: Noushka Reiter.
Many of those remnants are on private land. Nearly 90 species are recognised in Trust for Nature’s Statewide Conservation Plan as priorities for protection on private land, more than any other group of plants. Part of Trust for Nature’s focus has been protecting the remaining populations and habitat of these species, such as the Leafy Greenhood. The largest remaining population of this endangered species on private land is protected through a conservation covenant on the Mornington Peninsula. But sometimes more drastic measures are needed.
“I think orchids are emblematic of the loss of grassy woodlands in southern Australia,” says Adam Blake, Trust for Nature’s South West Area Manager. “Even in the places where we’ve still got woodlands, we’ve lost orchids. Through orchids we can start to understand the enormous complexity of biodiversity in Australia, but we often learn about the complexity of orchids when it’s too late.”
Reintroducing orchids to the wild
One of the people untangling the secrets of orchids is Dr. Noushka Reiter, Senior Conservation Scientist at Royal Botanic Gardens Victoria. At the gardens, Noushka and her team have grown more than 30,000 orchids from over 210 species. Together, they’re providing hope for some of Australia’s most endangered species, with the ultimate goal of returning orchids to the wild.
It all starts with a seed. Orchids produce thousands upon thousands of tiny seeds with almost no nutrition. These are carried easily by the wind, but to sprout they must settle on soil where they can partner with very specific species of fungi. These provide the new orchid with nutrients, and most continue the partnership throughout their lives.
Identifying and cultivating the fungus is the key to growing orchids. Until Noushka and her team began working on them two decades ago it was extremely difficult, but new propagation techniques she developed have unlocked the ability to cultivate the orchids en masse. It’s a long and fascinating process.
“The key is finding the right fungus,” says Noushka. “In winter we head out and isolate the fungi from wild orchids, and cultivate the fungi on petri dishes. We then go out in spring and pollinate wild plants and collect the seed. In the summer we put the fungi and the seed on the dishes. The seeds germinate over three months, then the seedlings go into flasks for six months, and after that into the nursery. They don’t get reintroduced into the wild for three years.”
Finding the right site is critical, a process that can take up to seven years. Noushka and other orchid scientists need to make sure the orchids’ pollinators are present, that habitat is suitable, and above all that it is secure. That’s where Trust for Nature, and landholders who have protected their properties with conservation covenants, come in.
“To ensure the long-term viability of populations we can only reintroduce orchids onto permanently protected land, like national parks or conservation covenants, where pollinators are present,” says Noushka. “On covenants often the landholders are really engaged, we couldn’t actually do the work without them.”
Botanist Rebecca Grinter has studied threatened orchids. Image: Rebecca Grinter.
In south west Victoria, Trust for Nature has worked with landholders, the Royal Botanic Gardens and orchid recovery teams to reintroduce orchids to six conservation covenants. They include some of the state’s most threatened species: the Tawny, Coloured, Candy, Yellow-lipped and Stuart Mill Spider-orchids. Around Melbourne, other orchids like the Rosella and Frankston Spider-orchids are being reintroduced on land protected through Trust for Nature.
“These species are at the precipice of extinction, whether these species survive or not depends on what happens in the lab and what happens when they go onto covenants and our reserves. It’s really knife-edge sort of stuff,” says Ben Cullen.
Fighting threats to orchids
Several hundred orchids are planted in plots on the properties, and then monitored carefully for threats. Understanding the best way to protect orchids is the subject of research by Rebecca Grinter, a Masters student at La Trobe University, whose studies have been supported by Trust for Nature’s Scholes Student Scholarship.
After working as a botanist Rebecca became entranced by orchids and set out to study Common Golden Moths, a grassy woodland species that is still widespread and common in Victoria.
“Like many orchids, researchers hadn’t previously looked at what pollinates these orchids, or what their threats are. But this information is critical for managing existing populations, and for identifying translocation sites for threatened orchids,” Rebecca says.
Rebecca discovered that the orchids are pollinated by several species of native bees, which are lured in by bright yellow flowers, but aren’t given nectar in return for their service. But she also made a surprising finding: nearly half the orchids in the two largest Victorian populations of Common Golden Moths were being eaten before they could produce seed. So she set up recording cameras to find out what was feasting on the orchids.
She soon found the culprits: kangaroos, possums, wallabies, and introduced animals like hares and rabbits were all grazing on the orchids.
“Orchids are often referred to as indicators for ecosystem health. Because of their complex ecology, you see them respond to changes in their environment more rapidly than you might in other species of plants. We can see that grazing by introduced species and overabundant native herbivores is a significant threat to the reproductive success of these orchids.”
Kangaroos are one of the herbivores that graze on orchids. Image: Rebecca Grinter.
That might also be the case for other grasslands orchids, including threatened species. Research like this is helping conservationists identify solutions, such as excluding native herbivores with cages while the orchids are flowering and fruiting, and controlling overabundant native herbivores and introduced species where appropriate. Keeping stock out, not spraying weeds near orchids, and avoiding high intensity fires can also be important, and making sure land management considers when the orchids are flowering and when they are dormant. After more than a decade of meticulous action, all this effort is starting to pay off.
“We’re starting to see the plants reproducing, creating self-sustaining wild populations,” says Adam Blake. “Private land has made a huge difference. Having access is so important, as is the security of a covenant, and educating landholders.”
And for those who want to learn more about these fascinating plants? Rebecca emphasises getting to know orchids without inadvertently harming them.
“If you see an orchid, look but don’t touch. You may find yourself looking at a species in danger of extinction given that so many Australian orchids are threatened, so always be cautious and respectful of their environment. There are lots of orchid groups you can join, and go on tours with experts.”
Through the efforts of people like Rebecca and Noushka, and the landholders that Trust for Nature works with, there’s hope for the future of Victoria’s orchids. So, next time you’re out in the bush, keep an eye out for these extraordinary flowers.
“Each one has its own story,” says Noushka. “They’re some of Australia’s most spectacular flowers. What’s not to love?”