Catching rats in the land of the undead
By Jack Ashby, on 10 February 2011
A delayed account of zoological fieldwork in Australia – Part 3
From April 2010 I spent about five months undertaking several zoological field projects across Australia. I worked with government agencies, universities and NGOs on conservation and ecology studies ranging from Tasmanian devil facial tumour disease, the effect of fire, rain and introduced predators on desert ecology and how to poison cats. This series of blog posts is a delayed account of my time in the field.
At the end of the post last week I was dropped at Two People’s Bay Nature Reserve. This is a small reserve managed by the Western Australian Department for Environment and Conservation (DEC), with whom I was working. I was asked to fulfil a few tasks while I was staying – the only resident of the research quarters. I felt a little isolated as it was out of season and there were no tourists around, and until my colleagues arrived in a few days, the only other people in the park were the rangers, who spent a lot of time away from their base.
One day I got up and spotted a long black scaly tail sticking out of the underneath of the fridge. The door of the cabin read “Keep door closed – fewer tiger snakes might get in”. This was the second disconcerting sign of the trip, our previous farm quarters on the cat poison trial read “Lot’s of flys. Keep door shut, ta”.
Tiger snakes are one of the bad ones. They are long, deadly and often black (some are dark with stripes). So to put my mind at rest I got on my belly with a torch and looked under the fridge. I saw legs. Relief! It was a massive King’s skink – a harmless lizard.
I would be joining a team of ecologists from DEC and the University of Western Australia who arrived in a few days to trap water rats. The traps we used are long cages with a treadle connected to a trap door by a hook. You put bait behind the treadle – the animals come in and tread on the treadle, which unhooks the door and it slams shut behind them. You check them in the morning and see what you catch.
Although water rats are widespread and common across much of their native Australia, relatively little is known about their ecology, so this study aimed to trap and radio collar them. Unfortunately we didn’t catch any before I had to leave for Tasmania, but there were plenty about (we found lots of empty closed cages with no bait – sometimes vegetation moves in and holds the door ajar).
I had a fair bit of time before the team arrived, so I could explore the beautiful coastal habitat I was in. Two People’s Bay is famous for animals that have come back from the dead. Two species in particular – Gilbert’s potoroo, a small kangaroo relative, and the semi-flightless noisy scrub bird – were both rediscovered in this tiny park, just 30 minutes from Albany – after an long period of being presumed extinct.
The potoroo was my main target, so I spent several hours each night wandering the forest looking for them. Most Australian mammals are crepuscular – they come out at dawn and dusk, and you are much more likely to see them at night than in the day. Some of the local mammals I got to know quickly and saw regularly. Reading and eating crisps one evening outside a quokka (a rare small kangaroo) came right up and tried to steal my snacks – a sure sign that the reserve’s visitors often feed these little marsupials. This is really bad for them as human food can cause infections that stop them eating altogether.
There are only 30-40 potoroos living wild in the world – all of them here (relocated populations are now being established on Bald Island). They are small and secretive and sadly despite long cold nights staring down my torch beam at every rustle, I didn’t find them. If I’d arrived a couple of months earlier I would have seen the captive study population, but that is nothing like seeing them wild.
I had some success with the noisy scrub birds though. As they don’t fly properly, just flitter around in dense scrub, it’s difficult to find them. Fortunately it’s not just a clever name – they have a very distinctive call which I feel privileged to have heard.
Visiting a place like Two People’s Bay – an island of protected habitat in a sea of farmland in one of the world’s biodiversity hotspots – I couldn’t help but be reminded of how difficult it is tell when a species is extinct. Gilbert’s potoroos and noisy scrub birds were both once written off, despite the fact that they lived just 35km from the region’s major town. Now they are both on the road to recovery – particularly the scrub bird.
I was sad to leave the Bay in the middle of the rat catching project (particularly as I hadn’t set eyes on one), I was very excited about my next project – trapping Tasmanian devils to study a contagious cancer which is set to wipe them out in the next few decades.
UPDATE: PART FOUR HERE