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)
Karajarri Rangers are leading a Threatened Species Recovery Hub research project to investigate how different fire management approaches affect biodiversity. The first field trip took place in April this year, when a team of 16 rangers, support staff and scientists journeyed to the Edgar Ranges for eight days of wildlife monitoring. Hub researcher Sarah Legge worked with the rangers to compile this report from the field.
Cissy Gore-Birch is a member of the Threatened Species Recovery Hub’s steering committee and the Chair of its Indigenous Reference Group. The Indigenous Reference Group was established to assist hub leaders and project teams to strengthen the engagement and participation of Indigenous people in the hub’s activities and research projects. Cissy recently attended the Species of the Desert Festival on the Paruku Indigenous Protected Area, where she spoke about both threatened and culturally important species, and increasing the voice of Indigenous people in environmental policies and research.
Dr Sally Box, the Australian Government’s Threatened Species Commissioner, talks about the importance of working with Indigenous groups to conserve Australia’s threatened species.
Researchers from the Threatened Species Recovery Hub are calling on citizen scientists to help them learn more about Australia’s possums and gliders by recording sightings in a new, free app. Dr Rochelle Steven from the University of Queensland is passionate about Australia’s possums and gliders and believes people in the community can do a lot to help support conservation, especially in urban areas.
There are 27 different types of possums and gliders in Australia. They have a huge variety of sizes, shapes and appearances. We’ve compiled a profile on every species here. One quarter of our possums and gliders are listed as threatened under Australian environmental law. Help their conservation, be a citizen scientist: you can record sightings of possums from your local areas in the free 'CAUL Urban Wildlife App'.