By Elaine Bayes, WetMAP field scientist
When you have camped out for 14 nights or so and mainly hear common species, it is a real thrill to go, ‘Did you hear that? What is that calling?’ Particularly if it is a species that mostly calls in winter and one you may not have heard for a couple of winters. This happened on a more adventurous frog survey a few weeks ago at Reedy Swamp near Shepparton. The call was of a species in the Whistling Frog group, which is composed of three species. Two of these sound and look very similar; the Plains Brown Tree Frog (Litoria paraewingi) and the Southern Brown Tree Frog (Litoria ewingii). [Check out the Featured Frog column for comparison – ed.].
This is where the amazing service of the Frog ID app comes in. Having tricky calls confirmed by an expert is a very handy tool, which we highly recommend before adding species to any of the current databases. So, having a few hours to kill while waiting on the RACV to come help us (we learned that you can over deflate your tyres while trying to get un-bogged!), I tried to get a really clear recording of the call with my Frog ID app. I waded out to the middle of the wetland and got as close as I could to what we believed to be Plains Brown Tree Frog calling from tall Juncus ingens (Giant Reed) in the centre of the wetland. Together with the recording and some great photographs by Damien, Frog ID confirmed the identification to the best of their current knowledge, but stated that in the future more research will be done on this group of frogs and the identification may be reassessed.
Another exciting find was the mostly winter-calling Sloane’s Froglet (Crinia sloanei) at the amazingly intact Doctors and Moodies Swamps. Both these sites had three Crinia species calling. These species are very similar looking, but we can tell them apart by their calls and some subtle differences like pattern on the bellies and the fact that Sloane’s Froglet has small orange-capped warts.
So fellow froggers, enjoy getting out to collect valuable data on your Frog ID app while this wet weather lasts. It will fill your soul with joy, and our databases with data.
Plains Brown Tree Frog, Litoria paraewingii by Damien Cook (Rakali Consulting)
Reedy Swamp, near Shepparton, Victoria. Photo by Dan Purdey