The second half of our journey took us to Katherine, and the impressive Nitmiluk National Park, before heading back north and then west to explore the splendid Litchfield National Park. In between these two destinations, I also snuck in a quick trip to the sandsheet heath around Batchelor for the NT’s only threatened frog species.
Nitmiluk NP is an gorgeous place. The Katherine River was in flood and watching the sunset from above the gorge was well worth it!
After sundown and driving my wife back to our accommodation in Katherine, I ventured back out to Nitmiluk in the moonlight, for what is the most southern extent of the little-known Jabiru Toadlet (Uperoleia arenicola). This species is quite difficult to differentiate from the widely-occurring Floodplain Toadlet (U. inundata). Knowing this, I would not be quick to conclude I had found the former species if I came across Uperoleia that night.
I soon ended up by a shallow sandy creek, winding its way through the sandstone rock formations. I had crossed this during the day and thought it looked promising. Upon my arrival, the chorus I heard some distance away was now very loud, with dozens of Uperoleia calling beside the sandy creek. Having spoken to several people with varying knowledge of the Upes of the NT, it would seem this is the Jabiru Toadlet.
The landscape was also crawling with these cool geckos.
Copeland’s Rock Frogs and Rockhole Frogs were also quite abundant.
As I descended back down the escarpment, I was stoked to stumble across this Masked Frog, another new species on my list to find this trip. They were definitely the scarcest rocketfrog to get onto during the trip.
Having left Katherine the next day, we travelled to Litchfield National Park, and spent the afternoon cooling off at Buley Rockhole cascades. I then had unfinished business to attend to: finding the Howard Springs Toadlet (Uperoleia daviesae). I dropped by the town of Batchelor to pick up Loan, a budding wildlife enthusiast who was working in the area at the time, and we headed back to the sandsheet heath country around Noonamah. Again, Floodplain Toadlets were calling everywhere, but amongst them we heard the softer call of the threatened toadlet. After a bit of triangulation (if you would call it that with only two people), we found this endemic frog.
Thrilled we had found our target frog, and glad to be back in the car away from the mosquitoes, our final stop was a return to Buley Rockhole for the Bilingual Froglet (Crinia bilingual) and the Territory’s only rainfrog, the Northern Territory Frog (Austrochaperina adelphe). Unfortunately, it had been a few days since any decent rainfall at the rockhole, and the afternoon storms missed this location, so I was unsure we would find the latter species.
Upon arriving at the site, and listening and searching for the Northern Territory Frog, we yielded no results. However, Loan did find the Bilingual Froglet down by the rockhole, where suitable habitat around the margins was present.
Our drive back through the national park to Batchelor also returned no locations of calling Northern Territory Frogs. Turns out we were not the only froggers to struggle with this species. Ecologist Anders Zimny, who hadn’t long moved to Darwin, was also searching for this species on the preceding nights, with no success.
With no more nights left of our trip outside of Darwin, I accepted 13 of 14 targets was still a pretty good outcome. For the final full day of our trip, my wife and I spent it waterfall-hopping through Litchfield NP. The waterfalls were all pumping and the cool, crystal-clear creeks offered welcome reprieve from the hot sun and high humidity.
A stroll along Greenant Creek and the lesser known Greenant Falls was our last walk and swim for the trip…but I couldn’t help notice the habitat along the creek looked ideal for the Northern Territory Frog I missed the night before. I flipped and put back a few pieces of fallen timber and palm fronds, and lo and behold, I uncovered the last frog I was looking for!
This is a stunning frog with blue flecks visible on the flanks!
Anders was encouraged by my find, and returned a day or two later where he also found one.
Our trip to the Northern Territory was one of our favourite and we can not wait to return again. It is so worth visiting in the wet season to witness the landscape alive with water and wildlife. It is a truly spectacular place!
We saw a very small frog on the wet rocks around Florence Falls yesterday. Do you know what it could be? It was only about 2cm and able to cling to near vertical wet rock face.