Roads, wildlife and a finished thesis


With the thesis finally vanquished (more on that in a later post), it’s high time I put together a bit of a summary of what I found. Thankfully I had the opportunity to write an article for the Ecological Society of Australia’s Bulletin which does exactly that, so I’ll repost it here. Make sure you check out the rest of the ESA Bulletin (here). It’s a cracker of an issue if you’re interested in anything to do with urban ecology.

So, with no further ado, here’s a bit of an overview of my field, my study and some very cool Australian mammals.

Roads, (huh) what are they good for?
People depend on roads. We use them to get to work, to move goods around the country or to take an iconic road trip. That’s probably why in Australia we have over 800 thousand kilometres of roads, driven by more than 15 million vehicles. But our need to travel can take a toll on the environment, especially our native wildlife.

The spread of roads across Australia. The areas in dark green are more than 1 km from the nearest road. The white areas are not. (credit Google Earth Engine)

The spread of roads across Australia. The areas in dark green are more than 1 km from the nearest road. The white areas are not. (credit Google Earth Engine)

The most obvious issue is roadkill. We’ve all seen the carcasses that litter the roadsides and maybe we’ve even been unlucky enough to hit an animal ourselves. Most motorists wouldn’t realise that the roadkill problem reaches far beyond the unlucky individual. When many animals are killed it can drain the local population, reducing numbers to a point where species can become locally extinct.

Then there are effects that aren’t so obvious. Some animals avoid walking out on to the road’s harsh, unfamiliar surface or shy away from the noise and open space. Others can’t physically make it across the gap a road creates in their habitat. This means they’re trapped on one side of the road, unable to reach food, shelter or mates on the opposite side.

I work in the field of road ecology, where we try and understand the environmental impacts of roads, trains and other linear things and find ways to put a stop to all of this carnage. When it comes to wildlife, we often build wildlife crossing structures – bridges over roads or tunnels under them – to allow animals to cross safely on their own. But how well do these structures work? I aimed to answer this question for one of our threatened mammals, the squirrel glider.

A threatened species in a threatening landscape
The squirrel glider is a small gliding marsupial that is threatened with extinction in the south-eastern parts of its range. They move by gliding from tree to tree, with an average distance of 30–40 m. Gliders depend on mature woodland with big old hollow-bearing trees. Unfortunately, in my study landscape of north-east Victoria, all that’s really left of the pre-European woodland occurs in linear strips, mostly along roadsides. So to conserve this species we need to make sure that they can survive and flourish in roadside habitats.

The only woodland that's left is along roadsides, paddocks and waterways.

The only woodland that’s left is along roadsides, paddocks and waterways.

One such roadside is the Hume, a four-lane interstate freeway. It’s travelled by about 10,000 vehicles per day, 25% of which occurs at night when native mammals like the squirrel glider are most active. The freeway ranges from 50–100 m wide and has been this way since it was upgraded around 40 years ago.

The problem
Those of you who are great at maths will have noticed that the width of the freeway is generally further than a squirrel glider can glide. Some researchers got to work investigating what sort of impact this had on squirrel glider populations. Through radiotracking studies they discovered that where treeless gap across the freeway was wider than 50 m, glider movement was heavily restricted (only 1 out of 50 crossed). Researchers also conducted mark-recapture surveys over 2.5 years and found that the survival rates of squirrel gliders living next to the freeway were 60% lower than those living further away. Gliders living along the freeway were facing a few challenges.

That's quite a gap for a small animal!

That’s quite a gap for a small animal!

Safe crossings for high-flying mammals
As a solution, two types of crossing structure were installed along the Freeway in 2007 – canopy bridges and glider poles. Canopy bridges are a kind of rope ladder, allowing animals to scurry across above the traffic. Glider poles are tall, wooden poles placed in the roadsides and centre median, and act as ‘stepping-stones’ for gliders to cross in a few short glides. Given that prior research had highlighted two key problems – barrier and survival effect – I wanted to see if crossing structures would increase movement across the road and improve the survival rates of squirrel gliders that lived alongside the freeway.
A rope bridge over the Hume Freeway in Victoria (left) and glider poles on the Hume Freeway in New South Wales (right)

A rope bridge over the Hume Freeway in Victoria (left) and glider poles on the Hume Freeway in New South Wales (right)

Spying and stalking
The first thing I looked at was animal movement, installing motion-triggered cameras to see if squirrel gliders would actually use canopy bridges and glider poles to cross the freeway. It took about two years before squirrel gliders got used to the structures and started crossing them regularly. In the seven years since, we’ve detected 1000’s of crossings. Gliders weren’t the only species making the most of the crossing structures. We also spotted brushtail possums, ringtail possums, sugar gliders, brush tailed phascogales and even a lace monitor making the trek across the freeway.
Squirrel Glider on a rope bridge over the Hume Freeway in north-east Victoria.

Squirrel Glider on a rope bridge over the Hume Freeway in north-east Victoria.

I was also able to look at movements in a little bit more detail. There were microchip scanners installed on the bridges so that if an already tagged animal went across, we’d know who it was. This showed me that several different individuals crossed the canopy bridges, some of them multiple times each night to reach habitat on both sides of the road. I worked with a masters student Meli Carmody, who repeated that earlier radiotracking study to investigate how road crossing behaviour had changed after the structures were installed. It turned out that where canopy bridges or glider poles had been installed, squirrel gliders were now able to cross the freeway at sites that had previously been a barrier to movement. At sites that were left with no structures, the freeway remained a barrier. This shows us that regular movements across the Hume Freeway wouldn’t be possible without crossing structures in place.
Our monitoring set up, complete with camera, microchip scanner and solar panels.

Our monitoring set up, complete with camera, microchip scanner and solar panels.

Gene flow
All this crossing activity was great, but did it result in gene flow? Were the animals that crossed the road “getting lucky” on the other side? To find out, mark-recapture surveys were conducted along the freeway to obtain tissue samples from squirrel gliders before and after the structures were installed. I was then able to use their genetic data to conduct a parentage analysis – identifying paternal and maternal relationships between individuals that lived on opposite sides of the freeway.

The analysis revealed that at sites where crossing structures were present, offspring occurred on the opposite side of the freeway to one or both of their parents. Somebody had to cross the road for this to happen! By cross-checking the identity of these family members with data from the cameras and microchip scanners, I was able to confirm that they had used the canopy bridges to cross the freeway. This reproductive success is an important component of gene flow and the effectiveness of crossing structures. Overall, I found that installing a crossing structure resulted in detectable improvements to gene flow within just five years.

A slide from one of my presentations, showing how family members occur on opposite sides of the freeway where a rope bridge is present.

A slide from one of my presentations, showing how family members occur on opposite sides of the freeway where a rope bridge is present.

Surviving in the danger zone
Finally, how did the crossing structures influence survival rates? The earlier mark-recapture study had identified a negative effect of the freeway on glider survival. I repeated that study, surveying for an additional five years after the structures were installed to see if survival rates had improved.

The results were surprising. It turns out that many of the animals that were missing and presumed dead at the end of the first study, were actually alive, and detected during later surveys in the second study. So the longer sampling period gave us a better estimate of survival rates because we had more of an opportunity to recapture previously tagged animals.

In light of all the other information, this finding actually makes a bit more sense. Radiotracking showed that gliders rarely crossed the road at sites where there were no crossing structures. If they’re not crossing the road, they can’t get hit by cars and so we wouldn’t expect survival to be reduced.

Monitoring effort matters
There’s more work to do, but ultimately my research suggests that crossing structures successfully reduce the effect of the road on squirrel gliders. I’ve showed that canopy bridges and glider poles can allow squirrel gliders to regularly cross the Hume Freeway, giving access to habitat on both sides as well as facilitating genetic exchange. But what I’ve really tried to show is that by using a comprehensive monitoring program we can be much more confident about how effectively crossing structures mitigate the negative impacts of roads on wildlife. Having information on movement, gene flow and survival collected before and after structures are installed was critical to getting the full picture.

When new roads are built, crossing structures are often installed as part of the environmental conditions of approval – granting permission for a road to potentially cause damage, on the assumption that a wildlife bridge or eco-tunnel will do the trick. If it turns out that these structures don’t work as well as we expected, not only are we wasting money on ineffective conservation measures, but we won’t know if we should be trying other things instead, or even seriously reconsidering where we allow roads to be built. Scientifically robust monitoring programs are the only way to truly understand these issues and make smart decisions for conservation.

As human populations spread, very few landscapes will remain road-free. Roads already cut through our national parks, conservation reserves and protected wildlife corridors. We must find ways of getting where we need to go without spoiling our natural heritage.

Related publications
Soanes K, Carmody Lobo M, Vesk PA, McCarthy MA, Moore JL, and van der Ree, R. (2013) Movement re-established but not restored: inferring the effectiveness of road-crossing mitigation by monitoring use. Biological Conservation. 159: 434–441.

McCall S, McCarthy MA, van der Ree R, Harper MJ, Cesarini S and Soanes K (2010) Evidence that a highway reduces apparent survival rates of Squirrel Gliders. Ecology and Society 15.

van der Ree R, Cesarini S, Sunnucks P, Moore JL, Taylor A (2010) Large gaps in canopy reduce road crossing by a gliding mammal. Ecology and Society 15.

Teaching wildlife road-crossing tricks


Do you know the most common question I get about wildlife crossing structures? Surprisingly, it’s not ‘do they work?’. It’s ‘how do you teach them how to use it?’. I understand why people are skeptical. Sure, a big, safe bridge for wildlife sounds like a great idea, but animals aren’t smart enough to know the difference between a safe spot and a dangerous spot. Are they? After all, they can’t even read! said no animal ever Thankfully, we don’t have to rely on wildlife commonsense. We road ecologists have a few tricks up our sleeves to make sure that animals do use these structures and don’t just cross wherever they feel like.

Location location location

Ideally, we’ve had a chance to study the animals living nearby before the road and crossing structures are put in. We spy on them with cameras, track them with GPS collars and generally stalk them about the country-side. If we can’t track them, we often know a bit about where they like to move through – do they travel along gullies or follow forest patches? From this we can build a map that shows their main movement corridors and pathways. Then we overlay where the new road will be built. Wherever the animal path crosses the road path is a good place for a structure. That way the animals don’t have to change their behaviour too much. They were going that way anyway.

A little bit of guidance

Still, animals have minds of their own and ultimately, can cross wherever they see fit. Maybe one day a new family moves in and decide they’d like to make a new path, a few 100 m away. How do we stop all our careful planning going to waste?

The fencing around the bottom to guides these Christmas Island crabs up and over

The fencing around the bottom to guides these Christmas Island crabs up and over

A fence. I know, it’s obvious when you think about it. We can put up fences where we don’t want animals to cross. Fences serve two important functions. First, they stop animals getting onto the road, creating traffic havoc and potentially getting killed. Second, fences guide animals to the structures, so that the structure is the only place the can cross. Unfortunately, fences can’t go on forever (that’s a lot of fencing!) but targeting them around key movement paths and crossing structures can be really effective.

It doesn’t happen overnight

Even with great planning and fencing, there can be a learning curve. Imagine you’re a deer. You’ve woken up in the morning and are heading off to your favourite waterhole for a quick drink before a day of frolicking (I assume this is how deer behave). Trotting merrily along, all of a sudden you come across this…thing, in your path. A strange, hard tunnel. You can see the waterhole on the other side, but the tunnel smells odd, and looks funny and generally gives you the heeby-jeebies. Better not risk it. Next time you come across the tunnel you’re feeling braver. The smell is fading and grass has started to grow around it. You might take a few steps inside before you chicken out. Then you take a few steps more, and more, until one day, you’ve made it all the way through. You think ‘Nothing bad happened. Maybe I’ll try that again… ‘ Anthropomorphism aside, animals usually take time to get used to the structures. How much time depends on the species. Black lion tamarins used a canopy bridge “as soon as it was assembled” (Valladares-Padua 1995), while larger, long-lived animals could take decades to adapt. My own work on squirrel gliders showed took up to 2 years before they started regularly using canopy bridges and glider poles (Soanes et al 2013).

Not just a cute idea

So, that’s how we do it. Scientists, engineers, road planners and environmental managers put a lot of thought into making each one as good as possible. After a structure is built there’s more work to do, figuring out how well it works and perfecting designs to make future structures even better. I’m not saying we’ve got it all figured out yet – there’s still a long way to go – but we’re learning all the time how to make safer roads for people and animals. Although this guy seems to have the situation under control…

“Don’t worry, ecologists. I got this.”

References and further reading

Valladares Padua C, Cullen Jr L and Padua S (1995) A pole bridge to avoid primate road kills. Neotropical Primates 3, 13-15.

Soanes K, Lobo MC, Vesk PA, Moore J, McCarthy MA and van der Ree R (2013) Movement re-established but not restored: Inferring the effectiveness of road-crossing mitigation for a gliding mammal by monitoring use. Biological Conservation 159, 434-441.

van der Ree R, Gulle N, Holland K, van der grift E, Mata C, Suarez F (2007) Overcoming the barrier effect of roads – how effective are mitigation strategies?, In International Conference on Ecology and Transportation. eds C.L. Irwin, D. Nelson, K.P. McDermott, pp. 423-431, Centre of Transportation and The Environment, North Carolina State University, Raleigh, North Carolina and Little Rock, Akansas, USA.

How to spot a late-stage PhD student

one does not simply, finish a phd

Yep, I’ve reached that stage of PhD research. The stage when you suddenly realise your analyses are mostly completed. You have graphs. You have answers. The only thing left is to figure out what the hell you think about them. And then to write it all down.

As a late-stage PhD researcher, you may exhibit some or all of the following behaviours.

You’ve stopped going to lab meetings. You no longer attend interesting seminars. You forgo group BBQs and faculty morning teas, except to quickly swoop through and pilfer some free food.

You start skipping committee meeting and workshops. At first you respond to invitations with thoughtful apologies. But eventually the list of unread or ignored emails looms large.

Your dependence on performance enhancing substances increases; caffeine, sugar and alcohol, all in your favourite forms (I like redbull, chocolate and wine).

You might even find yourself annoyed when you are forced to attend weddings, birthdays and other social distractions that other (normal) people look forward to.

I could say, ‘Maybe it’s just me…’ But I know I’m not alone. I know you’re out there. Single-mindedly dedicated to finishing your thesis, while at the same time desperately trawling the internet for anything, ANYTHING, to distract you. Perhaps you’ve stared at a word on the screen for so long that you’re sure it’s misspelled. Perhaps that word is your name.

Then again, maybe not. You might be a well-organised and well-adjusted individual. You might work solidly until 5pm then go home, not giving your thesis a second thought until you return at 9am the next morning. I might like to hide thumbtacks in your chair.

Try not to feel guilty about the borderline-antisocial behaviour that comes with late-stage thesis writing. It will pass. You’ll be a doctor soon! It’s right there. Tantalisingly and tortuously close.

In the mean time, take care of yourself and embrace your membership to this club of recluses. You can recognise other members by their complete ignorance of current movies or music and the inability to talk about anything other than their thesis.

Fear not my friends, for this is the stage of finishing! Finally your story comes together. All you have to do, is re-arrange that argument for the 100th time – then delete it entirely.

Further reading
Evidently, for some of us this is also the stage where we can no longer bear the self-imposed embargo on writing anything other than the thesis, and we rebel with a cheeky blog post. I recommend the following:
A letter to my thesis – Samantha Prendergast (One of my favourite reads)
Dear Thesis Whisperer, I’ve got Stockholm Syndrome – Ben from Literature Review HQ (via the Thesis Whisperer)
The nowhere-everywhere place – Maia Sauren (via the Thesis Whisperer)
When are you really finished with a PhD?– Lauren Gawne (via the Thesis Whisperer)

Introducing the Australasian Network for Ecology and Transportation

If you’ve read any of my previous posts, you’ll know that roads and traffic take a toll on the environment. You’ll also know that there is a whole field of research devoted to understanding and fixing the problem. Road ecology.

ksoanes_wildlife crossing

All over the world, road agencies, environment groups and scientists work to reduce the impacts of roads on the environment. They might build wildlife overpasses, reschedule construction so it doesn’t disrupt mating season, close roads during sensitive times or avoid building roads through protected areas. The details of these stories – successes, failures, and surprises – are often filed away on office shelves and forgotten. That’s the beauty of road ecology organisations like ICOET in the US and IENE in Europe. These networks hold regular meetings and conferences, ensuring that valuable lessons are shared.

Now one more group has set out to make information on road ecology more available – the Australasian Network for Ecology and Transportation, or ANET. To lift text straight from their website:

“We are a professional network dedicated to the research, design and implementation of environmentally-sensitive linear infrastructure (rail, roads and utility easements) across Australasia. ANET acts as a hub, providing links between government, industry, scientists and community groups to ensure all have access to current evidence and best-practice.”

While the network’s focus is on Australia, New Zealand and Asia, it’s open to anyone to join (it’s free) and contribute. In July 2014 the first ANET Conference will be held in Australia, showcasing the latest road ecology research.

Check out their website, Facebook and Twitter (@ecoltransnet) for more info and updates on road ecology, both here and abroad. Full disclosure, while this post isn’t on behalf of ANET, I am involved in the steering committee and run the Facebook and Twitter pages – so I’m not entirely impartial. Even so, I think it’s all pretty great and I’m excited to see how the network grows!

A sexist joke or a joke about sexism?

How do you tell the difference? A sexist joke is at the expense of the victim (for want of a better word). A joke about sexism is at the expense of the perpetrator.

Joe Hanson has a zest for science communication. He makes a series of short, science videos It’s OK to be smart which you can find on YouTube. Great examples of clear, engaging science communication.

In his Thanksgiving themed video, he made an error. He made Albert Einstein sexually harass Marie Curie.

See, the episode hinged on having bobble-head dolls of prominent scientists from the past sit around a table with him and discuss how far science has come since their time. To their dismay, not as far as they thought.

This is where the Einstein-on-Curie action occurs. Einstein repeatedly advances on Curie, then gets his gear off, then mounts her.

One of Joe’s points is that huge challenges still exist for women in science. As he explains to Curie in the video, only 14 women have won the Nobel Prize since she did, one of them her daughter. There are still major imbalances between men and women in senior positions, truly mind-boggling instances of sexual harassment and rampant implicit bias. All of these things need to change.

But Joe had to explain most of this in his post-video-backlash apology .

Why didn’t it come across in the video? Because, I’m sorry to say, the joke wasn’t well executed or funny. Jokes about ‘isms’ are tricky. The vulnerable party can’t be the butt of the joke. If you’ve ever watched The Office (you really should have), Ricky Gervais does this brilliantly as David Brent. Brent does and says some truly horrific things. But he’s always the one who looks bad. You know he’s in the wrong. The rest of the characters make it clear.

In the Thanksgiving video, no one calls Einstein out. Joe actually praises one of his pick-up lines. For it to work, Einstein had to be the butt of the joke. Curie could have kicked him off the table (I certainly would have). Any of the other scientists could have ridiculed him. Joe, as the moral, modern scientist could have called him out. Better yet, why not have a woman scientist co-host and give Einstein what-for? It had to be abundantly clear that Einstein’s behaviour was not OK.

Sexism should always be called out. Loudly and with gusto. I also think there’s a difference between someone who sets out to tell a sexist joke and someone who failed at making a joke about sexism. The end product was sexist, but the intention was not. I don’t think heads need to roll.

Instead, it’s a great opportunity to get the right message out there. That so many people immediately shouted, ‘That’s not OK!’, is brilliant (here, here, and here). Like others, I think this needs to become part of the video. At the end, explain the fall out. Explain why people were rightfully angry. Explain what you meant to do. Try again.

Getting the most out of the grant gauntlet

I’ve been meaning to write a post on research grants available to ecology and conservation students for a while now. In fact, I’ve been meaning to do it for so long that somebody else did it instead. Tim Doherty, quite thoughtlessly and, I think it’s clear, selfishly*, scooped me and published an excellent list here. Do read it.

It got me thinking about the first grant application I ever wrote. I didn’t finish it until the day it was due and only then did I realise it needed to be posted, not emailed. And printed on university letterhead signed by my supervisor. And include a copy of my academic transcript. In a blind panic, I faxed it (without those things) and hoped for the best. Needless to say, I was not successful. I’ve had a few more trips around the block since then, so I thought I’d share what I’ve learned as a student chasing funding. There’s a slight ecology focus, but I think most points are universal.

slowly lower in the grant money

Give them what they ask for
Address the criteria. On time. In the right format. With the correct attachments. It’s OK to ‘recycle’ material from other grant applications – you’ll often be applying for multiple grants at once to fund your project – but make sure you spend time putting it in the required format.

This means you need to…

Grant applications shouldn’t, and often can’t, be written and submitted the afternoon they’re due. Not only should you spend a bit of time thinking about and crafting your application (see this Research Whisperer post on half-baked grants), but there are logistic issues. They often ask for signed statements and references from supervisors, heads of school or industry partners. They might need to be printed on university letterhead, include scanned copies of academic transcripts or, heaven forbid, need to be submitted in hard copy. That all takes time. Supervisors will generally bend over backwards to help you, but if you start demanding things at the drop of a hat on a regular basis you will lose points very, very quickly.

Try and try again
Re-apply if they’ll let you (they usually do). I learned my lesson from that first dismal attempt and was awarded a grant in the next round.

Let them be the judge
You are not the judging panel. So don’t be the one to decide your work isn’t good enough, relevant enough or won’t win anyway so there’s no point in applying. That’s not up to you! Just address the criteria, be passionate, be honest, and let them decide. Which brings me to my next point…

A project can wear many hats. When applying for a grant, think about the parts of your work that are most interesting and relevant to their mission. Is it a conservation focus? A science focus? Are they keen on community outreach? Then frame it accordingly. You’ll be amazed at just how many different groups could be interested in your work. Be sensible about it though. If the grant is for work in arid ecosystems and you study coral reefs it might be best to look elsewhere.

Not just about the money
Whether you’re pursuing a career in research or will be an ‘on ground’ practitioner, you’ll need money to fund your projects. Learning to apply for grants is a critical skill. You won’t always succeed, and you won’t always enjoy it (rejection sucks), but you will improve with each attempt.

Grants are also a great opportunity to develop relationships with people and organisations in your field. In my experience they don’t just hand you a wad of cash, pat you on the head and send you on your way. They’re keen to hear about your progress, your findings and love to share your work with their members. This is a great opportunity to engage a new audience.

Where to look
If you’re in Australia, the JASON website is a great resource for post-grads, and if you’re working on conservation or ecology, definitely check out Tim’s list. Other good places to look are your university’s scholarship website, societies in your field, even local council or government departments. Also, don’t underestimate the power of a good Google search. Finally, chat to your supervisors and other students in the department and see where they find their money. In my experience, people’s desire to help overrides any competitive streaks they may have.

Happy hunting!