Australia

Misunderstood and Underappreciated: Our Native Rodents

Rodents.

Millions of people have a phobia of them and many more find them just plain revolting. They’ve been demonised more than a few times in popular culture – after all, J. K. Rowling certainly didn’t do them any favours with her character Scabbers. I’ve got to admit, for a long while I was among the people who scrunched up their faces at the idea of having to hold one. After doing some research though, my mind started to change – at least, for our Australian species. Rodents are the most abundant group of mammals on Earth, with over 2,700 species described within the group. Of these, more than 60 are found within Australia, across every state and territory.

The pebble-mound mouse. I mage: Wiki Commons

The pebble-mound mouse. Image: Wiki Commons

While some people may recoil at the idea of so many different rodents found throughout the nation, how they got here is actually quite extraordinary. Australia became a separate land mass 50 million years ago, but rodents reached the continent much more recently. The first wave of rodents arrived between five to eight million years ago, and the second wave, which was almost solely species within the genus Rattus, came in the last one million years. Both these waves were aided by the rising and falling sea levels around the Indonesian Islands, which are believed to be the origin point for our native rodent species.

Since their introduction to Australia, rodents have dispersed and diversified in extraordinary ways. In the northern states of Australia, a group of mice called pebble-mound mice are the only mammals on earth that construct mounds of small stones around burrows. Hopping mice are another unique group of rodents that are only found in Australia, moving in a hopping motion very similar to our native marsupials, despite there being no close relation between the two groups. In the southern states, the New Holland mouse is a social species that is particularly resilient to fire, with its population often increasing after an event. As well as being highly unique, rodents often aid the ecosystems in which they’re found, with recent studies finding that many species are responsible for spreading mycorrhizal fungi, which is crucial to the survival of various trees within Queensland’s tropical rainforests.

The New Holland mouse.  Image: Zoos Victoria

The New Holland mouse. Image: Zoos Victoria

If these species don’t fit in very well with what you imagine when you think ‘rodent’, it’s most likely because the images we typically have of rats and mice are actually invasive species. While the house mouse, black rat and brown rat are all found here, they were actually introduced by European settlers who brought them to Australia – and most of the world – on their ships. While Australian species can be carriers for disease, and it’s not advised for you to go and pick one up, it’s the invasive species that have been linked most closely to the spread of disease and infection.

Rodents make up about one quarter of Australia’s mammals, and are key parts of our environments and ecosystems – but unfortunately, despite their importance, they haven’t escaped the impact of their cousins’ reputations. Habitat destruction and predation from cats, dogs and foxes are major drivers for the decline of our native species. Despite this, funding for research and conservation for rodents is difficult to obtain, due to the stigma surrounding the words ‘mouse’ and ‘rat’. Since European settlement, half of our hopping mice species have gone extinct. Stick-nest rats, a group of rodents that construct their nests out of a variety of sticks and other plant material, are now extinct on mainland Australia. Many species, such as the smoky mouse, are being threatened by habitat destruction. As Australia’s human population increases, we continue to encroach on our native rodents and their habitats, often with devastating results. Since European settlement, an estimated 36% of native rodents have become extinct.

The rakali. Image: Zoos Victoria

The rakali. Image: Zoos Victoria

However, not all the news about our native rodents is bad. The water rat, also known as the rakali, has managed to recover after almost being driven to extinction. The species was nearly eradicated during the hunting trade of the 1930s and 1940s, and later in the 1950s due to people seeing it as a pest. Changes to permits as well as shifts in public attitudes have led to populations making a recovery. Similarly, the New Holland mouse was a species that was thought to have gone extinct for over 100 years, until its rediscovery in the 1960s in Sydney. Since then, conservation programs have been enforced to ensure that we don’t lose the species a second time around.

Approximately 91% of our rodent species are found nowhere else on Earth, and recent genetic work on some species indicates that the diversity may be even greater than what we can see taxonomically. But this diversity can only be preserved if we decide to protect and conserve these species. Like so many animals before them, rats and rodents are misunderstood – but we can change that misunderstanding, if we can just change our perception. 


Cover image by Billy Geary.

Review: Vegetation of Australian Riverine Landscapes

The Book – Vegetation of Australian Riverine Landscapes (Biology, Ecology and Management)
The Editors – Samantha Capon, Cassandra James, and Michael Reid

Riverine ecosystems are dynamic and diverse, and are strongly influenced by the flora that inhabit them. However, not only it is important to acknowledge how riverine plants influence their environment, but also to appreciate the processes that sustain our riverine vegetation. Vegetation of Australian Riverine Landscapes aims to encourage this appreciation, and to inspire interest in these fascinating landscapes.

Split into four sections, this book discusses the natural processes and anthropogenic impacts that affect the riverine vegetation of Australia, while also describing key taxa and the adaptations and life histories that allow them to exist in riverine habitats. The editors of this book hope that their text ‘fosters awareness of the incredible diversity and dynamic nature of riverine vegetation across Australia both for its own sake and for its vital functional role.’

The first section explores the spatial and temporal characteristics of riverine landscapes in Australia, and describes the diverse habitats determined by those characteristics. The history of our riverine vegetation is described, taking the reader on a journey from Australia’s most recent glacial period, through the Holocene, and into the present. This section also discusses the anthropogenic effects that alter our riverine habitats.

Section Two, named ‘Riverine plants’, discusses the key plant groups that are found in riverine habitats. Inconspicuous yet widespread, the bryophytes, aquatic algae, and charophytes are emphasised as functionally significant taxa in riverine environments. The diversity of vascular aquatic macrophytes and riparian herbs is discussed in this section, as is the ecology and life history characteristics that allow these taxa to survive in dynamic riverine environments. The larger, most noticeable species - the trees and shrubs - are also described in this section.

The third section in this book describes the riverine habitats of five major regions of the Australian continent, and how the vegetation varies depending on each region’s geographic location and climate. The floodplains and wetlands along the south-east coast of Australia are explored, including mangrove communities, coastal salt marshes, and brackish meadows. In contrast, the chapter devoted to inland south-eastern Australia describes the floristic characteristics of the Murray-Darling Basin as being dominated by woodland, forest and shrubland communities. The riparian vegetation of treeless high country is also discussed, as is the riparian vegetation of tropical northern Australia and the vegetation of desert river landscapes.

Finally, the authors describe the main management concerns regarding the riverine ecosystems of Australia. These include the consideration of various threats to our riverine landscapes, including water management, salinisation, fire, grazing and weeds. For example, while reviewing this book I learnt that at present there are over 3000 invasive plant species growing wild in Australia. These weeds account for 13% of Australia’s flora.  Luckily, restoration practices and monitoring techniques are also examined in this section.

Vegetation of Australian Riverine Landscapes lives true to its name, and provides an in-depth description of the plants and processes that are found in our Australian freshwater environments. Written in a succinct manner and with concise graphs and maps, this text will serve anyone interested in learning more about our riverine landscapes.

This book belongs on your bookshelf if… you're a student studying riverine ecosystems, you're interested in plants and how they adapt to their environment or if you're involved in land management.

Edge Pledge: A New Approach to Conservation Crowdfunding

The main thing that inspired Edge Pledge is that there’s not enough money to do what everyone wants to do for the environment. The issue isn’t that we don’t have good ideas or we don’t know what to do, it’s just that there’s not enough money to get it done.
Image: Marcia Riederer

Image: Marcia Riederer

This is not a new problem in conservation - not by a long stretch.  But it’s one that Sam Marwood hopes he has a solution to: “How do we get a whole new source of money, outside of government to resolve all these issues?”

Sam spent his childhood on a dairy farm and explains how much he loved living on the land: “My mum would grow trees from seed and plant them throughout the farm… I thought that was really cool. I loved seeing these trees grow and I loved seeing birds go in those trees. It’s like creating your own little natural world that these animals are really grateful for.”

For Sam, it’s this humble upbringing that eventually saw him complete an environmental science degree at university, followed by nearly a decade of work creating environmental policy. But he always felt that he could do more…

“One day I was thinking about Movember and how that’s a great independent source of money that comes from the public. I thought ‘Where’s the equivalent of that for the environment, where not only do you raise a lot of money, but you also raise awareness?’”

Thus, Edge Pledge was born: an online crowd-funding platform with a number of differences that set them apart, according to Sam. “We get people to put themselves on the edge for native animals that are on the edge of extinction.” This is done by issuing challenges (like doing a stand-up comedy show, or jumping out of a plane) through the platform, and people vote for which challenge a person should complete by donating money - all of which goes to bringing native animals back from the brink of extinction.

Why this concept? As Sam explains, it’s all about doing something different while still raising money for the environment and spreading awareness. “We didn’t want to do a fun run, we didn’t want to grow a moustache… So we thought ‘lets create a challenge generator that helps people figure out what challenge they want to do for the environment.’  

“So the Edge Pledge concept is that a challenge generator gives you three options for challenges and then your friends get to decide what you do [by donating money]. We thought that could be a powerful, fun way of raising money.”

Sam started Edge Pledge with friends Carys Evans, Nadia Nath and Dan Eason. Nadia and Carys worked with Sam across Victoria for over a decade in environmental management, and Dan (senior manager in accounting) has been a long term friend and was eager to be a part of the social movement.

And it seems like others are keen, too. Sam reels off an impressive array of businesses and individuals who are busy helping him and his team prep for the launch of Edge Pledge. Start-up wunderkinds Atlassian and behemoth Google are both involved in developing Edge Pledge’s online presence and Sam has enlisted celebrities like Gossling and Ash London to complete challenges at the launch.

“I originally thought I’d be working in government for the rest of my life. But I realized there are other ways to make a difference with the environment. So this idea of starting a social enterprise whose sole focus is raising money for the environment really, really excited me. We don’t want to duplicate what others are already doing though. We just want to add more money and raise awareness.”

Edge Pledge could help mammals like this feathertail glider.  Image: Marcia Riederer

Edge Pledge could help mammals like this feathertail glider. Image: Marcia Riederer

So, you might be thinking ‘Where is all the money that Edge Pledge hopes to raise going to go?’ Generally, Sam hopes to support “practical, landscape-scale projects assisting native animals on the brink of extinction.” Essentially, Sam and Edge Pledge don’t exist to duplicate the work already being done by a raft of conservation organisations. Rather, they intend to fill what is in their eyes an enormous gap – a source of regular, sustainable funding.

Indeed, a large portion of what Edge Pledge is hoping to do is simply to inject more fun and charisma into conservation fundraising. Central to that, Sam muses, is how conservation is framed more generally: “It’s been hard for us in trying to figure out our messaging. We’ve done user testing and people are like ‘I’m sorry but I didn’t even think about any of the animals as I was using the challenge generator. I didn’t even know what it was for, I just loved using the generator.’ And you think ‘Oh, maybe that’s okay because at least you’ve got your foot in the door, you do a challenge, you pick an animal to support and then the next six months you’re getting updates on how the animal’s going so maybe you care more about it over time.”

Aside from gradually converting every day people into conservationists, Edge Pledge aren’t out to reinvent the wheel: “We’re partnered with the best environmental organisations (e.g. Conservation Volunteers Australia) that have all the best processes in place, and have been doing it for years. We’re trusting the knowledge of our environmental partners and we’ve also got Brendan Wintle from the University of Melbourne and the Threatened Species Hub, who’s going to sit down with our list of projects from each of the partners and help us pick a couple from each to support.” Sam thinks that this two-pronged approach to prioritising which projects are funded by Edge Pledge will ensure their investment process is based on the best science and evidence available.

A shingleback lizard.  Image: Marcia Riederer

A shingleback lizard. Image: Marcia Riederer

Essential to the concept of Edge Pledge is thinking and dreaming big. However, Sam knows that it’s important to be realistic: “I don’t think Edge Pledge is going to raise the billions of dollars that we need [to conserve the environment], but what it will do is raise awareness to the public that they can do something tangible… then hopefully, the money will follow. I think what we have is an application that has the ability to go viral. But… most importantly, it’s about building on and supporting the great work that existing environmental organisations are doing.”

“I’m really excited that this could be one of the few easy ways that people can tangibly do something for the environment.”

For Edge Pledge, it’s all about helping people feel like they’re making a difference in a positive way: “You can do a tangible thing by doing a fun challenge and you know that the money you raise is going to support a native animal that lives close to you, and you can go see it and hang out with it.”

“It’s about being able to poke fun at yourself but doing it for a serious cause.”

For more information about Edge Pledge, head to their website: www.edgepledge.com

Cover image taken by Billy Geary.


Billy Geary
Billy is the Science & Conservation Editor at Wild Melbourne. He is a wildlife ecologist interested in predator-prey interactions and invasive species management.

You can find him on Twitter at: @billy_geary

Review: Finding the Mammals of Australia

The Book: The Complete Guide to Finding the Mammals of Australia
The Author: David Andrew


Aside from your friendly neighbourhood possums and the ever-present ensemble of feral animals, many of Australia’s mammal species are quite hard to come across. Indeed, some species are only encountered by chance or through technology like camera traps. This is clearly a difficult scenario for those enamoured with Australia’s amazing mammals.

Bird-watching guides are a dime a dozen these days, helping twitchers seek out particular species right across Australia. However, there has been a lack of similar guides for those hoping to seek out some of Australia’s elusive mammal species. The Complete Guide to Finding the Mammals of Australia, compiled by David Andrew, goes a long way to filling that gap.

For a start, this book is brilliantly put together. In its first section, Andrew has split Australia into different locations. For each location, Andrew lists the mammal species likely to be seen, including specific sites where encounters are possible. Not every location in every state is covered, though. Instead, Andrew selects a handful of locations likely to yield the most diverse set of mammal species. Some Victorian examples include Wilsons Promontory and the Little Desert region, both of which are home to unique mammal communities.

Dispersed throughout, Andrew details particular methods and techniques for spotting particular taxa, such as those that are particularly difficult to track, like cetaceans or bats. These groupings work quite well, given the propensity for these species to travel large distances. Similar breakout boxes see Andrew offer short summaries and comments on particular conservation issues in some areas, such as the plight of the Tasmanian devil. These sections offer valuable context for the reader who may otherwise be unfamiliar with location-specific issues.

The second major section is organized by species, detailing exactly where in Australia to find each of our fantastic mammals. As an example, Andrew suggests heading to Cranbourne Botanic Gardens south-east of Melbourne to ‘easily see’ the elusive southern brown bandicoot. Elsewhere, Andrew muses that one’s only hope of seeing a long-nosed potoroo would be through joining a scientific survey team.

Quips such as these are perhaps the most welcome aspect of Mammals of Australia. Andrew’s conversational style presents equally well when only a quick check of the guide is needed, or indeed when an entire expedition is being planned. Some sections feel as though one is reading a field notebook, rather than the polished product that CSIRO Publishing and Andrew have produced.

It would be foolish to brush off Mammals of Australia as simply a mere field guide, because it is so much more. Naturalists and biologists devoted to mammal-watching have been desperate for a resource such as this, given the sheer amount of similar literature available to bird watchers. Mammals of Australia should now be a vital part of any nature-based expedition.

This book belongs on your bookshelf if… you’re still trying to tick an elusive mammal off your list, or you generally love seeking out Australia’s diverse mammal fauna.