Radio Tracking Gilbert’s Potoroo at Mt Manypeaks.

Minang Country

This blog covers a week volunteering with the West Australian Parks and Wildlife monitoring the world’s rarest marsupial, the Gilbert’s Potoroo. There are estimated to be only 138 Gilbert’s Potoroo in the world. The animal is also part of a very prestigious club, being one of the few Australian Marsupials to “return from the grave.” Last recorded in the 1870’s it was rediscovered in Two Peoples Bay Nature Reserve in 1994 by a Ph.D. student trapping for Quokkas.

In addition to the original population at Two People’s Bay a further three “insurance” populations have been established. The first on nearby Bald Island that now holds upto 100 animals. The second, the 8.2km fenced enclosure at Waychinicup was where the radio-tracking was taking place, which now contains 25-30 animals. The final and most recent reintroduction has been of 10 animals to the Archipelago of the Recherche, off Esperance.

The value of the translocations was clearly shown in November 2015 when a band of lightning sparked a series of fires along the coast of South Western Australia. One of the fires was at Two People’s Bay where it destroyed 90% of the habitat of the original Gilbert’s Potoroo population. That population was reduced to a mere three animals, and had it not been for the translocations, the death knell for the species would have sounded.

The chances of seeing Gilbert’s Potoroo during the radio-tracking were virtually nil, as they live in very dense vegetation on the slopes and in the gullies between granite peaks. They seem to especially like stands of Melaleuca striata with an understory of sedge. Although I wouldn’t be seeing a Gilbert’s Potoroo, I decided to use my free time over the week to see if I could find other interesting wildlife of the South Coast, as both Two Peoples’s Bay Nature Reserve and Cheynes Beach were within a short drive of the survey enclosure at Mount Manypeaks.

Map showing location of Two Peoples Bay.

I left work Friday afternoon to make the long five hour drive from Perth down the Albany Highway to the South Coast. It was a warm March evening and the setting autumnal sun cast long shadows in the wheatfields.

I arrived at Two Peoples Bay Nature Reserve around 9.30pm and spotlighted the area around the Visitor Centre and Picnic Lawn. During the brief spotlight I found three Western Ringtail Possums in peppermint trees, a couple of Western Grey Kangaroos and numerous Motorbike Frogs dotted around on the ground or perched on low vegetation.

Motorbike Frog.

Camping is not allowed at Two Peoples Bay Nature Reserve, so before tiredness overtook me, I made the short drive to Cheynes Beach, where I spent a rather uncomfortable night sleeping in the 4WD.

I awoke early to a beautiful pink sky visible through the car windscreen. My first port of call was the excellent food van at Cheynes Beach Caravan Park, to get a breakfast wrap and and a much needed coffee! Replenished, I then walked a circular loop 4WD track with magnificent coastal views South to Mt Manypeaks and Cape Vancouver.

Spectacular Coastal Scenery Looking South from Cheynes Beach to Mount Manypeaks.

Ever hopeful for reptiles, I wasn’t surprised to find things quiet in the cool conditions, the exception being the Comb-eared Skink below that was making the most of the short bursts of sunshine.

Comb-eared Skink.

Early afternoon, I made the short drive to the accomodation for the upcoming survey week, a farmhouse on Homestead Road. Driving along the back roads I encountered a beautiful Southern Heath Monitor basking on Waychinicup Road. This was one of around eight of this species seen over the course of the following week.

Southern Heath Monitor Belly Down on the Warm Road Surface.

Monitor lizards, in common with the snakes, have a forked tongue to help them determine the direction from which an odour is originating. They do this by detecting minute differences in odour-causing particles on the two tines of the forked tongue once the tongue is retreated into the mouth and placed against a sensory organ there. If the odour is stronger on one side, then the source of the odour is in that direction. Humans use a similar method to this to elicit the direction of a sound, thanks to the distance between our ears.

Forked Tongue of the Southern Heath Monitor.

Once at the farmhouse, which was magnificently situated in the shadow of Mount Manypeaks, I met the other members of the survey team. We were twelve volunteers, plus the two parks and wildlife staff. The twelve of us were to man the potoroo tracking stations in shifts while the two parks and wildlife staff were to take it in turns to drive us to and from the enclosure to the farmhouse. We were a motley but jolly bunch!

Waychinicup Enclosure Potoroo Tracking Team – 2020.

The purpose of the week was to learn more about the basic biology of the Gilbert’s Potoroo in the wild, especially to assist in selection and management of translocation sites. To enable this small radio-transmitters had been attached to the tails of 8 different potoroos.

There were four fixed tracking stations established within the potoroo colony. Each station consisted of a 6m mast fitted with two large aerials on top, and connected to a receiver. The mast and aerials were swivelled by means of a handle until the signals indicate the aerial is pointing directly at an animal. The direction is then read from a compass rose with an indicator needle. A tent shelter and seat were also provided for the tracker.

Radio-tracking Station.

Radio-tracking was carried out daily to cover the entire active period of the potoroos. This meant three teams of four covering three shifts of six hours. The shifts were 2pm until 8pm, 8pm until 2am and the horror 2am until 8am. The teams were rotated through these different shifts with my team experiencing each shift twice.

Although the work was monotonous, and later in the week made extremely difficult by the weather, it was fantastic to spend the shift of six hours sitting out in the bush in this beautiful corner of Western Australia. The highlight of the daytime shift was undoubtedly to watch the colour changes effected on nearby Mt Manypeaks by the setting sun.

Tracking station dwarfed by the majesty of the granite domed 565m Mt Manypeaks.

The 8pm until 2am shifts was the best for wildlife, especially when driving to and from the tracking stations, with both Quokkas and Bandicoots regularly seen. A Tawny Frogmouth became a regular feature sitting on the enclosure fence as we drove past for the nightime shift swap. While manning the Manypeaks Tracking Station on the 8pm until 2am shift, my brief walk between readings saw an encounter with this adorable Western Ringtail Possum.

Western Ringtail Possum.

Even the dreaded 2am till 8am shift had a highlight, because to watch dawn from the first subtle colour change of the dark night from black to purple, right through to the kaleidoscope of colours at sunrise was a magical experience, one as humans we experience all too rarely, locked up in our urban world.

Sunrise over Western Australia’s South Coast.

During the week there was spare time between shifts, so I put this to good use exploring the surrounding coastline, which consisted of stunning granite peaks interspersed with beautiful remote, empty beaches.

Hakea cucullata overlooking the sandy sweep of Two Peoples Bay.

Point Vancouver and an endemic West Australian Grass Tree (Kingia Australis.)

View North to Mount Manypeaks and the Potoroo Haven of Bald Island.

Twice over the course of the week, when shifts allowed, I made the short drive to nearby Cheynes Beach. Here on both nights I located around eight Honey Possums with the thermal imager. Finding a Honey Possum with a thermal imager and getting a photo are two entirely diffrent things! Once a feeding Honey Possum is illuminated by torchlight, it is apt to drop out of the bush and into the dense heath below. The one exception to this was the animal pictured below that was feeding in a flowering Yate Tree (Eucalyptus cornuta,) that obligingly froze for a photo.

Honey Possum Feeding on Yate Flower.

Wherever there is such a rich abundance of prey there will be predators, and this Boobook Owl no doubt, makes a fine living in such Honey Possum rich habitat.

Boobook Owl.

Conditions during the last two days became very difficult out in the field when rain and strong winds moved in. It was hard enough at the best of times trying to listen to the faint beep of eight often distant potoroo tracking beacons, but to do so when rain was hammering on the tent shelter and the wind was whipping up sand into the shelter made the task almost impossible at times.

Finally 2am on Saturday morning our team completed the concluding shift. Back at the farmhouse I fell into bed exhausted. Saturday morning the wild weather of the previous two days was clearing so after helping dismantle the field stations at the enclosure I briefly considered returning to Perth and my soft bed, but instead I elected for another night in the tent looking for wildlife and so drove once again to Cheynes Beach.

I arrrived late afternoon and it was all I could do to get the tent up before crashing for another hours sleep. After a hearty fish and chips at the food van I wandered around the caravan park finding lots of Western Grey Kangaroos emerging from the vegetation in the overcast conditions to graze the grass of the caravan park.

Western Grey Kangaroo.

I made the short drive to nearby Two Peoples’s Bay at dusk to have a final spotlight there (this time also using my thermal imager.) Driving at dusk was a poor decision but due to a sensible and much reduced speed I managed to dodge the many Kangaroos that tried to kamakaze the car.

The conditions at Two Peoples’s Bay were perfect for thermal imaging with no moon and plenty of cloud cover, best of all were windy conditions to obscure the sound of my footsteps.

The largest number of Western Ringtail Possums I had previously encountered spotlighting Two Peoples’s Bay had been three animals, but this number was doubled to six with the aid of the thermal imager.

On the lawns of the Picnic Area I picked up a small fast moving heat image with the thermal imager. Moving in on the heat source I turned on the spotlight to find a Mardo (Yellow-footed Antechinus) frozen on the rough bark of a peppermint tree on which it was foraging for insects.

I had only once seen this species before, and that was in daylight. It was an awesome find and I was truly delighted, although over the course of the evening I had another two sightings of Mardo with the thermal imager more than proving its worth with this light shy species.

Yellow-footed Antechinus or Mardo.

The Southern Brown Bandicoot or Quenda is another species found at Two Peoples Bay, but despite accounts of others finding this species here, a sighting had always eluded me. Once again the thermal camera and conditions came into their own when I picked up two of this species. One on the picnic lawn and a second animal on the paths near the Visitor Centre.

Southern Brown Bandicoot or Quenda.

Over the course of the evening I also found a number of Quokkas and a Bush Rat. The Bush Rat disappeared into the thick sedge undergrowth before I could get a photo, but I had a little more luck with the Quokkas, especially with the animal below which I suspect was blind in the left eye.

Quokka.

Shortly after this more rain hit, so I retreated to the car and then returned to Cheynes Beach and my warm tent. A big storm came through that night or so I heard the following morning because I slept through the whole damn thing, wind, rain and all, when the disrupted sleep of the previous week finally caught up with me.

The following morning I made the drive back to Perth and decided alter my route slightly to drive through the Stirling Range. The Stirling Range is one of the most unique national parks in Western Australia running sixty kilometres from West to East, and encompassing an ancient mountain range. It is home to 1500 plant species more than the number in the entire Bristish Isles!

While all eyes were on the East of Australia during this years terrible bushfire season, a fire started by lightning burnt through the Eastern half of the Stirling Range NP. To see it in person I couldn’t believe the destruction. EVERYTHING had been burnt, even the alpine regions at the top of the highest peaks, it was utter carnage. The wildlife and plant species that have been lost must be huge. Hopefully this National treasure will regenerate over time but it was with a heavy heart I drove on.

Bushfire destruction in the Stirling Range NP.

On the return journey to Perth there was one last wildlife surprise with a White-faced Heron sitting high in a tree over Coalling Creek at Williams. A traffic bridge passes over the creek which was fortunately at the perfect height from which to photograph the impressive bird.

There can be no doubt that the Potoroo volunteering was hard work, but the opportunity to spend a week on Western Australia’s stunning South Coast with a fabulous bunch of people was worth all the effort. It was also a great opportunity to gain experience with my new thermal imager, and very much a relief to find that this expensive piece of equipment is starting to pay dividends!

#QuollingAround