Wildlife relocation programme “Climate change has dramatically exacerbated the situation”

A brushtail bettong (small kangaroo), in the background two people
Relocation of a brush-tailed betong, a small kangaroo species | Photo (detail): © Australian Wildlife Conservancy

Australia's wildlife is unique, but many species are threatened. The Australian Wildlife Conservancy (AWC) translocation program is successfully fighting for their preservation.

Ms Anson AWC runs the largest wildlife translocation program in Australia. What species are you concerned with?

We specialize in small and medium-sized mammals. In recent years, I've overseen the translocation of several endangered marsupial species, including bilby, numbat and bettong. Our eight fenced sanctuaries are spread across the continent, plus one island in Western Australia. One of the largest of the fenced reserves is Newhaven Wildlife Sanctuary in the Northern Territory, where we are in the process of reintroducing at least nine threatened species. In all, AWC has moved nearly 7,000 individuals of 32 threatened species to areas where they have a good chance of survival over the past two decades.

Wouldn't it be easier and safer to protect the animals where they live?

Yes, of course! Translocation is only part of our strategy. Many of our mammal species have disappeared from much of their historical range and are now extremely rare, so translocations allow us to re-establish populations where they used to exist. Australian wildlife is unique, with 80 percent of the local mammal species found nowhere else in the world. At the same time, we have the highest extinction rate for mammals, a sad record. In the last 200 years, at least 34 mammal species have gone extinct – and those are just the ones we know about.

What's the reason?

First, the domestic cats and foxes brought to Australia by European settlers. Some landowners didn't want to give up fox hunting when they came here! These predators quickly spread and became a catastrophic problem for small mammals. Other threats include habitat loss and the impacts of poorly-managed fire. These are compounded by climate change, which has dramatically exacerbated the situation. In recent years, Australia has experienced more – and more devastating - wildfires and floods than ever before. Shrunken and isolated animal populations are particularly vulnerable to such disasters.

How do you protect the animals from these threats in their new habitat?

We reintroduce them into a national network of fenced areas, as well as one island. In Newhaven, a 44-kilometer cat-proof protective fence has been constructed to enclose an area of nearly 9,500 hectares. AWC also conducts fire management within our sanctuaries: applying low-intensity fire at the right time of year to prevent the spread of larger more destructive fires. Similar techniques have been used by Aboriginal Australians for thousands of years.

What exactly is the procedure for relocating a species?

First, we gather comprehensive biological information about the species, based on which the search for a suitable area begins: How big does the habitat need to be, are there sufficient food sources, where can the animals find shelter, what threats are they exposed to and how can they be managed or removed? The project can only be successful if all these questions have been answered satisfactorily. Once the habitat is found, we coordinate the plans with the regional governments and with other conservation agencies. In the next step, we consider how many animals to relocate and from which populations to take them. It is important that the animals come from several different populations so that genetic diversity is maintained.

And then you set traps?

Exactly. The trapped animals are examined for diseases and fitted with trackers before being released into the new habitat. In some cases, when the wild population of a species has already diminished so much that we can only catch very few specimens, we interpose a short breeding program – most small Australian mammals reproduce quickly.  The whole process can take one or two years.

And that‘s the end of the project?

No, the subsequent monitoring also takes several years. With the help of trackers, we can monitor the physical condition the animals are in, how active they are, whether they are reproducing – even who is sharing the burrow with whom! Only once did we have to cancel a translocation because of a severe heat wave, which would have caused too much stress for the animals to acclimate. Otherwise, our projects have been successful.

Which animal species do you plan to introduce next?

We have plans to reintroduce the Golden Bandicoot to Newhaven and a marsupial carnivore called the Western Quoll to Mount Gibson in 2023. There are many more species that could benefit from translocation. In a study of existing protected areas, a team of researchers from seven Australian universities specifically lists nearly 30 threatened species - including several species of wallaby, small kangaroo-like bettongs, possums and tree rat species. In the study, they also recommend creating more and larger refuges as quickly as possible.

The relocation of animal and plant species is very controversially discussed in science. How do you prevent the newcomers from harming other animals or plants, perhaps even displacing other species?
This question plays a very important role for us! Before conducting reintroductions, we look at the areas very carefully in this respect as well, to be sure that the resources are sufficient for the animals. Of course, an ecosystem changes when an animal species is added. But in our projects, these effects are actually beneficial: Bilbies, for example, make widely branching burrows and loosen the soil as they dig, which is good for vegetation. They spread plant seeds as they move around the landscape. And in their tunnels other small mammals find shelter when it is very hot or very cold outside. In Australia there is now broad consensus that translocation of threatened species should be a necessary component of conservation efforts if we hope to prevent any further extinctions.

So can you always be sure that the benefits outweigh the risks? Another Australian animal welfare organization wants to fly endangered South African white rhinos across the Indian Ocean and release them in Australia....

Moving animals to a completely different ecosystem is not something I would support! The species we are translocating were once common in Australia. So the risks are manageable, and we can anticipate and control them well. In the meantime, we have also gained a lot of experience and are constantly learning - also from other projects, because there are more and more examples of translocations of endangered animal and plant species worldwide. Species extinction has accelerated at such an alarming rate that I think doing nothing is the biggest risk!

Managed relocation

Managed relocation (assisted colonisation/assisted migration/translocation) is the planned relocation of threatened animals or plants to another habitat where they have good survival conditions. Decades ago, wolves were successfully resettled in Yellowstone National Park and black bears in Arkansas. For some time now, there have been increasing efforts to reintroduce endangered species to areas where they were not native in the past. This is justified by the effects of climate change on habitats, to which many species cannot adapt quickly enough. This form of assisted migration in particular is rejected by many researchers because the risks are too high: the newly settled species could displace other animals and plants through introduced diseases or uncontrolled reproduction and upset the balance of entire ecosystems.