Wednesday, March 25, 2015

Pink Eared Duck



For the next few days I will posting a few water birds. Probably a good way to start the series is by the most cutest of the lot- The Pink eared duck (Malacorhynchus membranaceus ). A pretty looking duck with a spatula like beak. It is called the pink eared duck, because it has a small pink spot near it's eye (though the female does not have the spot) . The duck is also called a zebra duck, because of its patterns. Its unusual bill is highly specialised and is fringed with fine grooves, which  filter out the microscopic plants and animals which make up the bulk of its diet. The water enters through the tip of the bill and after getting filtered is expelled along the sides.
I spotted this solitary duck at the Hunter wetland area.

Tuesday, March 24, 2015

Yellow-tailed Black Cockatoo



Australia has five species of black Cockatoo's and these black Cockatoo's are endemic to Australia and found nowhere else in the world. I was so delighted to spot one of these blacks, that despite it not being a good image, I anyway decided to post it on the blog.
The bird is the Yellow-tailed Black Cockatoo (Calyptorhynchus funereus ) once called by John Gould as the Funeral Cockatoo. Four of these five black Cockatoo's are listed as threatened. The population of Yellow-tailed too is declining and may be a matter of time before it joins the other four. Loss of habitat and illegal pet trade are the primary reasons for their decline.
Now for some interesting- Although Cockatoo's are related to the parrots, they are never found in green or blue colour, like the parrots. Colours in birds are produced not just by pigments, but by microscopically structured surface on the feathers. When light reflects of these surface from various layers, it causes interference. The greens and the blues are caused by something called constructive interference and the structure responsible for it is called the Dyck texture. Cockatoo's lack this structure in their feathers hence the lack of greens and blues in them.

Monday, March 23, 2015

Superb Fairy Wren



Both the images are of a male Superb Fairy wren (Malurus cyaneus), a gleaming, velvety blue and black bird. The male is so colourful that it is hard to miss it- so hard to miss, that I missed out on photographing the female ! Other than the colourful plumage this wren leads a colourful life too. The birds are monogamous and pair for life, but they are also sexually promiscuous, which means that each partner will mate with other individuals and they will raise the chicks together born out of such mating. So infidelity is quite the norm, despite the monogamy.
As a part of their courtship display the male plucks and offers yellow petals to the female. This restless insectivorous bird, also has an interesting way to identify parasitic cuckoo in their nest (see previous post). It uses a unique song as a password, which only the superb wrens chicks respond to. A very interesting bird indeed. The bird is found only in Eastern Australia and Tasmania. 

Sunday, March 22, 2015

Fan-tailed Cuckoo


The first thing most of us remember when we thing about the cuckoo, is its ingenious way of dodging the perils and labours of incubation by depositing their eggs in the  nest of some other bird and allowing them to rear its young. Those exactly where my thoughts when I saw this Fan-tailed Cuckoo ( Cacomantis flabelliformis ) in Australia, which incidentally was also my first cuckoo sighting down under. To avoid having their eggs thrown out by the foster parents cuckoos have developed a colouration to their eggs that matches with those species they parasitise, so each race of cuckoo restricts itself to only certain species. This Fan-tailed chooses flycatchers, fairy-wrens, scrubwrens and thornbills, the Brown Thornbill being a particular favourite.  A single egg is laid in the nest and one of the host's eggs removed. The young cuckoo generally hatches earlier than the host's eggs and proceeds to eject the other eggs or hatchlings. The seemingly unaware foster parents then rear the cuckoo chick.
It was an amazing feeling to see a cuckoo here and it reminded me so much of the Indian cuckoo. 

Friday, March 20, 2015

Gang Gang Cockatoo







The sheer variety of Parrots in Australia has left me wondering on how evolution has been shaped by isolation. While the parrots I am used to in India are mostly green, I wonder how they managed to come in such huge variety of colours and hues in Australia. Previously I have posted a White Cockatoo, a multi coloured  lorikeet  and today is another contrast a Black Cockatoo. Commonly called the Gang gang Cockatoo (Callocephalon fimbriatum ) I spotted a male and the female in the blue mountains. The male has a scarlet head and the female has a grey head and crest, with both sexes having yellow edged plumage. 
Biologists are still trying to find a satisfactory answer to this variation in plumage and hopefully they will get and answer sooner than later. Meanwhile, my quest to see as many of the 40 different parrots found only in Australia continues. 
The name Gang gang, is very interesting. It is derived from an  onomatopoeic aboriginal name. Many aboriginal names have reduplication like Rainbow Lorikeet is wirritywirrity, white sea eagle is makmak, tyunguttyungut is fgrogmouth owl and so on. 

In the photographs, the top is the mature Male, Followed by Juvenile and the last two are females. 

That's all for now- have a nice day.  


Thursday, March 19, 2015

Laughing Kookaburra



As the batsmen of the 2015 ICC world-cup are facing the Kookaburra balls, I had the delight to face the real Kookaburra- the Laughing Kookaburra (Dacelo novaeguineae ).
The Kookaburra belongs to the Kingfisher family and is the worlds biggest Kingfisher. Its call, which it makes to mark its territory sounded like a laughter to whoever named it- well not to me though. They hunt like kingfishers and eat a variety of prey, including fish, small snakes, lizards, rodents, worms, beetles and other insects. It is a pretty common bird in Australia, found both around human settlements and forests. The kookaburra is one classical example of a bird, which is severely affected by the pesticides used in farming.  The pesticides used to kill insects, end up poisoning the animals which usually feed on those pests. When kookaburras eat contaminated insects, they absorb the pesticide chemicals and store them in their fat. When food is in short supply and the kookaburras use some of their fat store, high concentrations of chemicals may flow into the blood. The result can be reproductive losses or even death.
I had a very wonderful evening with this lovely bird- I even managed to sip a cup of tea, watching the Kookaburra bully other birds that were trying to hunt alongside it. A wonderful bird indeed!

Wednesday, March 18, 2015

The Glow worm tunnel

Today's is a very special post-partly inspired by David  Attenborough's documentary 'Life in the Undergrowth'. In episode 3,  Attenborough visits New Zealand's Waitomo Caves in which the larvae of fungus gnats illuminate the cave, and use their beaded filaments to lure their prey. In Australia, in the Blue Mountains region is a similar place called the 'Glow worm tunnel' - this is the story of our visit there.
After a 30 Km off-road bumpy drive which took us through some beautiful landscapes and a tunnel, we reached a desolate corner in the Wollemi National Park.



It was a further 2 Km trek to the coveted tunnel.




A special hug to my wife, Aarina, here, who despite her apprehensions of dark and desolates caves, decided to accompany me into the tunnel.


The entrance to the tunnel was partly covered by overhanging ferns and the floor was covered by a gently flowing stream of water.


Inside the tunnel its completely dark, eerily quiet. All I could hear was trickling water, my own heart beat and Aari's footsteps.



The larvae of a fungus gnat (small, short lived fly) resides in these tunnel. They are called  Arachnocampa richardsae and they can create their own light or scientifically speaking, have bio-luminescence. They sit put on the walls of these caves or tunnel and drop in a sticky silk line. This line has mucus on it which look like beaded necklaces. Any flying insect that touches these lines, stick to it and becomes the larva's meal.


To attract insects close to their snares, the larva glows. Many insects are attracted to this light and inadvertently, get stuck onto the sticky snare, the gnat then pulls the snare and feeds on the prey.

To see the glow, we switched off our lights and waited for our eyes to adjust to the darkness. Slowly, we could see the entire tunnel beautifully illuminated, like stars that illuminate a dark sky.



A feeling of joy, ecstasy and accomplishment filled us up! A delightful warm embrace in a silent cave studded with glowing worms is something that we will never wish to forget!