The Search for the Green Tree Frog

The Australian green tree frog would have to be one of Australias most iconic frog species. It is large and very docile, making it a popular pet around the world. it is spread across Australia, with a southern limit of around Wollongong, right up to Cape York, and has a wide distribution in semi-arid western areas. It is very common to encounter within most of their distribution, everywhere except for developed areas, especially Sydney. We have seen a drastic decline of these otherwise common amphibians within the last decade. So in this species of the week we will cover the general ecology of the green tree frog but also send out a message of suspected reasons why they may be declining and to encourage people to look out for these beautiful frogs.

The green tree frog has some interesting ecological traits. One of the most interesting is that they are sporadic callers and males will mainly only call in response to thunder and will chorus really heavily the following day after a thunder storm. Their preferred breeding habitat is ephermal (temporary) pools, that collect after heavy rain, but will also breed in more permanent water bodies as long as they are still (not flowing i.e. a river). The terrestrial habitat they prefer is open woodland; not to dense, but still have a canopy to take refuge in.

 

Green Tree Frog (Litoria caerulea) caught at Gloucester | Copyright Chad Beranek (2013)

Green Tree Frog (Litoria caerulea) caught at Gloucester | Copyright Chad Beranek (2013)

 

After asking around a lot, it seems these frogs use to be all over Sydney. The question is, why are they gone? Some obvious reasons are habitat clearance due to development, which removes the suitable habitat trees they shelter in, and you could also hypothesise that due to their docile nature, they would be susceptible to predation and attacks by cats. Another idea put forward (By Aaron Payne, Personal Communication 2014), is that the breeding habitat that they use is being removed in urban areas due to curb and guttering. This drains and removes all the temporary pools that collect consequentially removing the preferred breeding habitat of the green tree frog.

 

Green Tree Frog | Copyright Chad Beranek (2013)

Green Tree Frog | Copyright Chad Beranek (2013)

 

 

This is a real issue as it would be very upsetting to loose these iconic frogs from Sydney. Recently I have been focusing on trying to find a population in the Sutherland Shire region. After asking around a lot and checking the records, the last populations people have seen were in 2001 around the Jannali area and also right near Sutherland Hospital. There has also been reports of green tree frogs coming from up north which have started breeding but die off in the winter. To tell the difference between a green tree frog from the north and the south; the southern green tree frogs will only have green and white coloration, where the northern green tree frogs will have green and yellow coloration.

See Aaron Payne (c) Photos:

Southern

Green Tree Frog (Litoria caerulea)

Northern

Green Tree Frog (Litoria caerulea)

 

And one last note, the last green tree frog that has been seen and reported in the urban areas of Sutherland Shire (excluding the Royal National Park) was this one found in Kirrawee last year (see link below, Aaron Payne (c)), right near the brick pit (which is now also being developed). If you are a Sutherland Shire resident and have seen this frog anywhere within the Sutherland Shire, please let me know ASAP. I am really looking hard for these guys as I would like them to persist and would they be a lovely asset of beautiful fauna to preserve within Sydney and the Sutherland Shire.

Green Tree Frog (Litoria caerulea)

 

With a collective body of knowledge from all interested residents we may be able to locate them and preserve them, then hopefully ensure they become more abundant.

If you have had any recent sightings of the Green Tree Frog please contact me: gumnutnaturalist@gmail.com