The Casuarina Corridor of Life

At this time of year the days are becoming colder and most animals are becoming less active, or migrated north. This stillness and quietness of winter becomes evident. However there are a few specific vegetation communities which can occasionally provide an abundance of life in the onset of winter, and it’s all controlled by food. One of these vegetation communities are the Casuarina swamp lands which line undisturbed river lines in eastern Australia. Most inland rivers are cloaked by the River She-oak (Casuarina cunninghamiana), usually 20 meters each side of the bank, but sometimes more or sometimes less depending on the geological architecture of the area.

 

Tree top view of a Casuarina swampland along Wollondilly River.

Tree top view of a Casuarina swampland along Wollondilly River.

 

 

These Casuarina swamp lands can become a very important niche for many different species of birds during the onset of winter. The reason for this does not lie with the Casuarinas specifically, but surprisingly a parasitic plant which lives on the Casuarinas. These plants are known as mistletoes. While mistletoes have adapted to mimic a multitude of different host tree species, the mimicracy displayed by the Needle-leaf Mistletoe (Amyema cambagei) is extraordinary. This mistletoe has evolved to mimic Casuarinas and Allocasuarinas, and does a remarkable job of disguising itself amoung the Casuarina needles. Unless you are a mistletoe expert, the only sure-fire way to discern mistletoe from Casurina is to witness the Needle-leaf Mistletoe in flower (which are incredibly beautiful and unique!). Casuarina flowers are much different from mistletoe flowers and look like small fluffly red or brown parts on the leaves (needles), while the Needle-leaf Mistletoe flowers have large bright red anthers that a readily distinguishable, and are probably that bright to attract the birds!

 

Needle-leaf Mistletoe (Amyema cambagei)

Needle-leaf Mistletoe (Amyema cambagei)

 

The Needle-leaf mistletoe usually flowers at the beginning of spring, however I must of been at the right place at the right time as thousands of Needle-leaf Mistletoe were in flower, giving the Casaurinas bright red highlights which contrast well among their dull foliage. This earlier flowering could probably be due to the large quantities of rain south eastern Australia has had in the preceding months. With waning nectar resources from other tree and plant species, it seemed all the nectar feeding birds in the area decided to take advantage. We were treated to an avain frenzy of tweets and feathers. There were many bird species I didn’t manage to get a photo of and many bird calls I couldn’t identify, but below are some notable entries.

 

Yellow-faced Honey Eater (Lichenostomus chrysops), preparing for flight.

Yellow-faced Honey Eater (Lichenostomus chrysops), preparing for flight.

A Mistletoe Bird (Dicaeum hirundinaceum), flutter around the canopy tops in the Casuarina.

A Mistletoe Bird (Dicaeum hirundinaceum), flutter around the canopy tops in the Casuarina.

Golden Whistler (Pachycephala pectoralis), eyeing off a flowering mistletoe target.

Golden Whistler (Pachycephala pectoralis), eyeing off a flowering mistletoe target.

Brown Thornbill (Acanthiza pusila)

Brown Thornbill (Acanthiza pusila)

Eastern Spinebill (Acanthorhynchus tenuirostris)

Eastern Spinebill (Acanthorhynchus tenuirostris)

A mating pair of Turquoise Parrots (Neophema pulchella) take off.

A mating pair of Turquoise Parrots (Neophema pulchella) take off.

 

The last bird shown above is the Turquoise Parrot which is threatened in NSW. This was an especially great find! They even landed for me to take a photo, however they chose the ugliest invasive weed species to land on, I was in any case excited.

 

Turquoise Parrot (Neophema pulchella)

 

While the bird life was astonishing, there were other appearances which you usually only get to see in areas which are healthy and remote from urban development. The area harboring this biodiversity is situated between Nattai NP and Yerranderie Conservation Area along Wollondilly River, which gives wildlife to solitude it needs to become especially diverse and abundant. The healthy sections of this river is known to be home to the Platypus (Ornithorhynchus anatinus), which I was especially lucky and excited to witness. The photo isn’t great but I was able to view it with binoculars as it would emerge and submerged for ten meters. On the banks of the river I was also able to see a healthy Common Wombat (Vombatus ursinus) grazing, and well as huge amounts of butterflies fluttering around, which turned out to be the Monarch Butterfly (Danaus plexippus) and Lesser Wanderers (Danuas chrysippus). I am unsure if these butterflies were here for the mistletoe nectar or for some kind of migration.

 

Platypus frolicking in Wollondilly River.

Platypus frolicking in Wollondilly River.

A healthy looking wombat, seemingly untouched by the current wombat disease epidemic, mange.

A healthy looking wombat, seemingly untouched by the current wombat disease epidemic, mange.

Monarch Butterfly (Danaus plexippus). This butterfly is a male, which is distinguishable by the pair of black dots on the lower wings.

Monarch Butterfly (Danaus plexippus). This butterfly is a male, which is distinguishable by the pair of black dots on the lower wings.

 

 

To witness this spectacle of nature was an inspiring reminder that there are still untouched oases of life which escape the reach of man with the addition of wonder with how many features of animal ecology remains unknown.

 

 

The Blue Mountains Stream Frog

Found near the tops of mountains in areas near Sydney, the blue mountains stream frog resides. This species of the week is on a locally uncommon frog which usually goes unnoticed with most attention being paid to the endangered frogs. The blue mountains stream frog inhabits sandstone creeks in high altitude areas where is it well adapted for this habitat. Areas it is found includes the Blue Mountains and Darkes Forest. It quite large for a frog has powerful and agile legs, perfect for jumping along rocky sandstone banks and swimming through fast flowing mountain creeks.

 

Blue Mountains Stream Frog (Litoria citropa) | Copyright Lucy Kidson (2014)

Blue Mountains Stream Frog (Litoria citropa) | Copyright Lucy Kidson (2014)

 

The blue mountains stream frog can be very varied in coloration, but will always have a red tinge under their arms and legs. Most of the time they are flanked by green (which can be almost fluro!) and have a brown top, with darker lines outlining their head. Some specimens can be almost completely green, but will maintain the head outline.

 

Blue Mountains Stream Frog | Copyright Lucy Kidson (2014)

Red coloration under the arms and legs | Copyright Lucy Kidson (2014)

Green morph of the Blue Mountains Stream Frog | Copyright Lucy Kidson (2014)

Green morph of the Blue Mountains Stream Frog | Copyright Lucy Kidson (2014)

 

They begin calling usually around the middle of September with the first onset of warm weather followed by rain. They have a very soft call which can be difficult to detect when there is wind and flowing water about. They have a soft call due to the absence of a voice box. Even though they are usually hard to hear, in contrary to most other frogs, they are much easier to find when you get a creek they are present in. From September to January, they will be found all over creeks in high altitudes, usually on the sandstone banks, but may occasionally be seen perched up on ferns and branches of shrubs. If you are lucky enough, you may find some in amplexus in small pools to the sides of the creek.

 

Litoria citropa in amplexus | Copyright Lucy Kidson (2014)

Litoria citropa in amplexus | Copyright Lucy Kidson (2014)

 

Blue Mountains Stream Frog (Litoria citropa) | Copyright Lucy Kidson (2014)

Blue Mountains Stream Frog in a fern | Copyright Lucy Kidson (2014)

 

And if you are especially lucky, you may even have one jump on your face!

 

Face frog

Face frog