Hungry herbivores, fungal diseases and long hot summers are just a few of the challenges land managers face when attempting to re-introduce a threatened
plant species. But the biggest challenge of all may lie in calculating whether a reintroduction program has been successful.
“When we reintroduce a threatened plant species, we do so with the goal of creating a viable population that will be self-sustaining into the future,” says project leader Dr David Coates, from the Department of Parks and Wildlife, WA.
“The aim of our project [Project 4.3] is to examine the methods we use in our programs, in order to improve our success rates.”
Dr Coates and his team face a series of inter-related problems that begin with the challenges of propagation.
“Some of these species require unusual techniques to get them going, for example we need to use fire to extract the seeds from banksia cones.
“Sometimes seeds don’t propagate easily, either due to the specific soil mix or the difficulty of creating the right conditions. And other times we just don’t know why a particular species struggles to get going.
“We must always remain conscious that in the case of particularly rare species, we don’t have large amounts of seed to begin with, so we need to be very careful. Our margin for error is small.”
Even if the propagation is successful, the team must work to find a suitable habitat to reintroduce the young plants, and ensure there are no immediate threats.
“In Western Australia we are always on the lookout for dieback, which is an introduced pathogen and devastating soil-borne fungal disease. For the most part we can’t really combat it, other than by preventing access by people to affected areas to minimise its spread,” says Dr Coates.
“Both feral and native animal grazing are also threats, they are typically curious about our activities and have a taste for young seedlings. If we don’t fence them out, they will eat everything.
“We also need to keep an eye on the weather. Long hot summers can quickly undo all of our hard work and initial watering may be needed to assist establishment.”
In order to achieve the ultimate goal - a self-sustaining and viable population, a critical number of plants must survive to reproductive maturity.
“This will be a major focus of our research, looking at ways we can both measure and model levels of pollination, reproduction, recruitment and genetic variation. This will be challenging in some cases where the lifespan of a number of the shrubs and trees will usually outlast the lifespan of any given project.”
“We can then benchmark these results against natural populations.”
“It’s essentially a numbers game, where we need to discover how many plants need to be established in order to ensure a species’ survival. At the moment we aim for at least 250, but depending on the species, we may need many more.”
“Our research aims to provide the answers to these questions.”
Image: Lambertia orbifolia - Round-leaf Honeysuckle by Tatters/Flickr (CC BY-NC 2.0)
The University of Melbourne and the Threatened Species Recovery Hub are offering opportunities for Indigenous students to do PhDs on research in conservation and management of biodiversity, and threatened species.
Translocation is a very important tool in the fight against plant extinctions. Knowing when to do translocations, how to do them and how to measure their success can be a complicated business, especially considering the huge range of threatened plants in Australia. So where do you find the answers? Luckily, they are now all in one place, in new guidelines that will be a game changer for plant translocation. Dr Lucy Commander lets us know what is on offer.
We are offering an honours project looking at feral cats in two national parks. The student will analyse spatial data to quantify and compare home range, habitat use, and activity times of feral cats at both sites, and interpret these data in terms of risks to threatened species at the sites (bridled nailtail wallabies, bilbies, and others), and ecology and control of invasive predators.
Fifteen tiny quoll pouch-young have been born to three female eastern quolls from a pioneer group of 20 animals released into Booderee National Park. In a big win for the reintroduction project, these are the first eastern quolls known to be born in the wild on the Australian mainland for more than 50 years.
Mouse-sized carnivorous marsupial the Endangered Kangaroo Island dunnart has only rarely been seen in the past 20 years. TSR Hub researcher Rosemary Hohnen is on the job working with local partners to develop better monitoring methods for the elusive species, and to evaluate the impact of feral cats on its persistence. Here she gives us a taste of the action, and despite the tiny size of the mammal there is a lot of heavy lifting…