Gone Troppo (or Up a Tree)

There are roughly 54 species of frogs in the Wet Tropics Bioregion of Far North Queensland (from Cooktown to Townsville) and about 25 of these occur in Cairns (at least that was the estimate before the severe drought of 2000 to 2003).

Just a smattering of information about local tree frogs is presented here. For more details about any of Australia's 220 + species of frogs, read "The Field Guide to Australian Frogs" by Barker, Grigg and Tyler, (c) 1995.

Litoria infrafrenata (White-lipped or Giant tree frog)

Arguably Australia's biggest frog (depending on which published reference you are referring to), the White-lipped is easily seen and has adapted readily to living around human habitation. It's preferred habitat is the flooded pandanus and melaleuca swamp but this habitat is threatened and there is little remaining in Cairns. This species is also the most common 'patient' at the Cairns Frog Hospital due to injuries incurred around homes. Diseases, parasites and cancer also affect this species to a serious extent. It can live to over ten years in the wild and reach 12 to 15 cm in length but this frog has to avoid a lot of threats for a lot of years to reach those milestones.

Litoria caerulea (Common Green tree frog)

Perhaps the world's most commonly kept pet frog, the Common Green has an endearing expression and adapts well to living around humans although it would rather be in a very leafy forest environment. However, it's status is the wild is beginning to arouse suspicion as more and more observations are made that L. caerulea is not being found in many of the places it used to occupy in the past. A statewide survey has been undertaken in New South Wales to determine if this frog might be in trouble. It is also the second most common patient at the Cairns Frog Hospital after the White-lipped tree frog. It is the second species targeted by the immuno-deficiency complex and this species is turned in for herbicide poisoning more than any other species we receive at the Cairns Frog Hospital.

Litoria gracilenta (Graceful or Dainty tree frog)

Green above and yellow below, this small frog is commonly heard in leafy suburbs and rainforest in the region. It is also a common freeloader when it comes to getting a ride to other parts of Australia, doing a first-class con job on unsuspecting bananas (and banana handlers) by successfully and frequently scoring free trips to southern Australian cities. It very closely resembles the Northern Red-eyed tree frog to all but the discerning eye - but their calls easily tell them apart. Most Gracefuls reach about 4 to 5 cm length but larger individuals up to 6 cm can be encountered occasionally. Like other local tree frogs, Graceful metamorphs look nothing like the adults, being a golden tan colour with a stripe above the lip. After about six weeks, the dorsal surface goes green and the stripe fades out.

Litoria fallax/bicolor (Eastern and Northern Dwarf Reed/Sedge frogs)

Very difficult to tell apart are these two tiny frogs which are only 20mm long in the northern part of their range (although the Eastern Dwarf Sedge frog reaches about 30mm long in the southern part of its range). They are just as likely to be heard calling in the middle of a hot, sunny afternoon as on a rainy evening. They also take advantage of bananas as free transport south but their southern counterparts like to travel north as well. This frog has been found in various produce departments of Coles, Piccone's and other importers and sellers hiding in all sorts of leafy vegetables. If you should find one of these frogs when you are shopping or unpack your groceries, please turn it in to us. There are serious diseases down south and we need to quarantine these transported frogs so that they don't spread these diseases here.

Litoria xanthomera (Northern Red-eyed tree frog)

This frog disappears for most of the year and suddenly reappears in groups once the conditions are right for breeding. The conditions desired by this frog are very wet and we do mean VERY wet! This pretty frog can be heard after cyclones (hurricanes) have passed through or after the heavy torrential rains the tropic north receives when the monsoon trough has arrived. Its call is most distinctive with a series of droning moans followed by a series of chirpy little 'burrrrrr's and it calls in groups, in unison. It looks very similar to the L. gracilenta described above but is larger and its colouration deeper, including its reddish eyes. The snout is a rounded point whereas the Graceful has a blunt snout that looks chopped off.

It's favourite habitat is a rainforest close to a creek so suburbs that back onto bush are more likely to have this frog around. In the summer of 2001/02, we did not get a wet season and so this frog compromised its calling preferences in a desperate effort to breed. Rather than wait for heavy rain, this frog was out in small numbers calling after short periods of light rain. The metamorphs, like other local tree frogs, do not resemble the adults at all. They can be very speckled and the overall body is brown. They will become green within two months of metamorphosis.

Litoria rothii (Roth's tree frog)

This frog seems to be patchily scattered around a few suburbs in Cairns and seems to like forests, both dry and wet. A swampy habitat suits this species as well and it calls from the trees. L. rothi is a very changable frog from day to night. When found sleeping during the day, its body is a pale putty colour without pattern. At night, however, it changes to a heavily blotched frog with dark brown blotches on a putty background - no doubt related to camoflage for tree branches and trunks. One distinctive ID characteristic of this frog is found on the back of its thighs and that is a vibrant black and yellow "cow pattern" of spots. Its call sounds like laughter that gets lower. Unfortunately, most of the Roth's that have been turned in for care have been attacked by cats in the newer housing estates that back onto bush.

Litoria rubella (Desert, Brown or Naked tree frog)

This is still a common frog in Cairns and likes hanging around under the eaves of houses and on the outside of windows at night. It only reaches 3 cm and is normally coloured putty to pale brown which can flush to middle brown or a reddish brown when stressed. Because of the lack of a wet season in 2001/02, insects were in short supply and many insectivores expanded their food selection to other items. We received reports of geckos attacking these little frogs as well as an injured one to prove the point. Green ants also attack and kill these frogs so eliminating green ants from your property is very beneficial to frogs (in more ways than one).

Litoria microbelos (Javelin frog)

We do not have a photo of this tiny tree frog - Australia's smallest - and getting a photo in Cairns will be a real challenge. This frog prefers swampy conditions and it appears to be sensitive to disturbance. While the Curator has seen and heard this species at Yorkey's Knob and Yarrabah when she arrived in Cairns ten years ago, she hasn't seen it since. It might still be hanging on somewhere in Cairns but only just.

More tree frogs are included in the Declining Frogs page and the ground dwellers page. The miniature tree frogs (microhylids) have their own page as well.

Last edited: Oct. 1st, 2005