Realising that you’ve made a mistake is usually a discouraging experience, but there are a few exceptions to the rule. Realising that a presumed extinct species is still alive and kicking is one of these happy exceptions.
Cases of mistaken extinction are more common than you might think, especially if it is a species that moves around a lot, is very small, or lives in dense habitat. But it’s a little harder to fathom how one could misplace a plant species that is quite literally rooted to the ground, on a very small island. And yet, this is exactly what happened with the hero of our story, the elusive Subantarctic Bedstraw (Galium antarcticum). The plant seemingly disappeared from its island home, only to reappear – no explanations, just going about its usual plant business – some 30 odd years later.
Despite its name, the Subantarctic Bedstraw doesn’t look anything like straw. It is actually a small purple herb with dainty white flowers, which grows close to the ground. Our diminutive hero occurs in just a handful of locations throughout the world, including Australia’s very own subantarctic Macquarie Island.
Researchers first identified the Bedstraw on Macquarie in the early 1980s, but after this sighting, the plant seemingly disappeared. Despite scientists launching several search parties over the decades, the plant was nowhere to be found. Researchers eventually concluded that the species was gone for good.
Then on one fateful day in 2013, over 30 years since it was last seen, scientists Nick Fitzgerald and Jennie Whinnam found themselves nearby the last known location of the Bedstraw, Skua Lake. While they weren’t hopeful of finding the Bedstraw, they also couldn’t resist having a look for our lost friend. Needless to say, the pair were overjoyed – and very surprised – to have their curiosity rewarded when they did indeed locate the presumed extinct species.
It wasn’t just single plant or two either, but around five hundred of them! Then four years later, PhD student Cath Dickson found another Bedstraw population of around 1000 on the other side of the lake. This essentially tripled the known numbers of the species in one fell swoop.
So what on earth happened? How did this plant elude us for so long, and how and why did it return?
Let’s start with the location. For those unfamiliar with Macquarie Island, it is a tiny remote island half way between Tasmania and Antarctica. The island is uninhabited except for researchers and the occasional adventurous tourist. Affectionately called ‘Macca’ by its few local residents, the island’s weird and wonderful geology and natural beauty make it quite unlike anywhere else on the planet. It is also home to many non-human residents, including plenty of other unique vegetation, colonies of penguins, seals and seabirds.
Despite these many attractions, Macca is also what some might call ‘inhospitable’. Sitting directly in the path of storms sweeping in from Antarctica, rough seas, wind, rain, hail and snow are a common occurrence on Macquarie. The island is also so remote requires you to mount an actual expedition – by ship – to get there. So … the island isn’t exactly over-run with hordes of people combing the island with magnifying glasses, looking for lost plants.
Maybe the Bedstraw was always there, and the search parties just missed it. Plants are, after all, less likely to be recognised or noticed by people than other wildlife. This explanation seems unlikely however, given how close the Bedstraw was to other monitoring sites regularly visited by island scientists. Further, the people searching were plant specialists accustomed to the difficult subantarctic conditions. As Fitzgerald says “Doing research in extreme environments is challenging but also exciting. Now if I am working on a particularly cold and windy day in Tasmania I think “well this is just like an average day in the subantarctic, where you wouldn’t think twice about doing fieldwork!”. Of course, having the right clothing and equipment is critical to being able to work safely and relatively comfortably in inclement weather conditions”.
During the three decades that the Bedstraw was MIA, there were some other big factors at play. Like so much of Australia, Macca had played unwilling host to multiple, dangerous invasive species for over a hundred years. Seal hunters introduced rabbits, along with cats, rats and mice, in the 1870s. These species are prolific, and soon Macquarie Island was teeming with them. In the early 2000s, the Australian Government successfully eradicated cats from the island. The departure of the cats had an unfortunate side effect, however. The cats had been acting as predators to the rabbit population, and without their influence, the rabbit population boomed. The speed at which rabbits reproduce and decimate vegetation has devastated native biota in Australia, and Macquarie Island was no exception.
While they can’t be sure, researchers think the vast army of rabbits grazed the Bedstraw down to almost nothing. With so few tiny plants left, the chance of anyone finding them was miniscule to none. But, all was not lost. The Australian Government was about to launch the largest and most intensive pest eradication program ever attempted in Australia. The program was to become one of the most successful island conservation programs in the world. Beginning in 2007, the Government waged a relentless, and ultimately successful, campaign against these pests. No one has seen a rabbit, rat or mouse on Macquarie Island since 2011.
Since then, inhabitants of the island have seen a transformation in the island’s wildlife, including grasses, insects, fungi and seabirds. And so, the rediscovery of our friend, the Subantarctic Bedstraw, may be a symptom of broader ecological resurgence.
As one of the few people in the world to see the recovery firsthand, Nick Fitzgerald feels positive about the future … “The dramatic changes that humans and introduced species have made in remote areas such as the subantarctic shows the value of science for documenting these changes and managing wild places for nature. It is a privilege to get to visit places like Macquarie Island and very rewarding to see evidence-based solutions to environmental problems achieving rewilding of degraded ecosystems”.
- Denholm, M. 2019. The miracle of Macquarie Island, The Australian.
- Balas, B. and Momsen, J.L., 2014. Attention “Blinks” Differently for Plants and Animals. CBE—Life Sciences Education, 13(3), 437-443.
- Fitzgerald, N. 2015. The mysterious case of the Subantarctic Bedstraw. Far South Ecology.
- Fitzgerald, N. 2019. How I stumbled on a lost plant just north of Antarctica. The Conversation.
- Monash University. 2017. Monash discovery triples critically endangered plant population. Phys.Org.
- Shaw, J., Terauds, A. and Bergstrom, D., 2011. Rapid commencement of ecosystem recovery following aerial baiting on sub‐Antarctic Macquarie Island. Ecological Management & Restoration, 12(3), 241-244.
- Springer, K., 2016. Methodology and challenges of a complex multi-species eradication in the sub-Antarctic and immediate effects of invasive species removal. New Zealand Journal of Ecology, 40(2), 273-278.
- University of Queensland. 2017. Watching Macquarie Island transform after a massive intervention. Threatened Species Recovery Hub.
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