Sunday 12 March 2017

Mud glorious mud!

There are many types of Wetlands and most are complex ecosystems and most require a drying phase as part of their life cycle to promote rejuvenation. As water levels vary the micro habitats within wetlands change, presenting new foraging opportunities for birds suitably equipped and adapted to take advantage of the changing conditions.
                                                  
As the season changes in East Gippsland from a dry summer to, so far, a dry autumn, Macleod Morass near Bairnsdale is drying out in some sections exposing large areas of mud with stranded and exposed fish and macro invertebrate life forms. This creates new opportunities for other organisms to grow by exploiting the changing conditions.  

Late last week I spent three hours from just before sunrise observing birds feeding on a mud flat at Macleod Morass. The following photos and captions give an insight to the birds exploiting this ephemeral environment.

Please click on photos to enlarge.

A section of the mud flats at Macleod Morass. The white birds are Black-winged Stilts.

Five species of waders including Black-winged Stilts, Red-kneed Dotterels, Black-fronted Dotterels, Masked Lapwings and Sharp-tailed Sandpipers were exploiting the muddy conditions.

The Black-winged Stilts were the “stars of the show” with at least 40 actively foraging for tiny organisms on and in the mud and the remaining shallow sections of water. The Stilts have had a successful breeding season judging by the good number of juvenile birds in the flock.

There are two adults and five juvenile birds in this photo.

Adult Black-winged Stilt.
Ditto

Note the mud on the raised foot.

Juvenile Black-winged Stilt.
Ditto
Long leg stretch.

The juveniles at times looked like they were still coming to grips with their incredibly long and spindly legs. 
The young birds managed to stay pristinely clean in the muddy conditions, just like their parents.


 
Standing on this piece of pipe was an attraction for a number of birds.
The Black-fronted Dotterels stayed well away – too far for photos.

A Black-winged stilt dwarfs two Red-kneed Dotterels.  

Clearly in overall size, but especially in bill and leg length, the Stilt and Dotterel are equipped very differently. The range of water depths these two species can exploit varies greatly.

The Black-fronted Dotterels were on the mud for the whole three hours I was there. They foraged intermittently and loafed and preened in between. The Red-kneed Dotterels by comparison only arrived on the mud from a nearby dry resting area after I had been there for about 1 ½ hours and then only stayed for about half an hour. They seemed far more nervous and prone to take flight compared to the Black-fronted Dotterels.

Juvenile – immature Red-kneed Dotterel.
Something has spooked the Red-kneed Dotterels and this lot have come together and are alert with heads stretched high.

How this Red-kneed Dotterel has managed to have a bath without being plastered with mud I don’t know.

Sharp-tailed Sandpipers, or should that be Mudpipers, feeding on the mud flat.
About fifteen Grey Teal were working their bills hard in the mud without let up while I was there.

The bird above looked up briefly when it heard my camera shutter.
The Purple Swamphens were one of the heavier birds on the mud flat though they were mostly just crossing over and not feeding in the mud.

There were large numbers of Magpie-larks foraging on the mud. A heavily cropped version of this image shows a tiny fly in the bill.
This male White-fronted Chat was the smallest and lightest bird feeding on the mud. About six were feeding along the margins of the mud flat.
The male above looks up in response to the sound of my camera shutter.
The female White-fronted Chat.
Even a fox appeared on the mud flat nosing about for food.

An Australian White Ibis has captured a stranded eel. I saw ibis capture 3 eels in this way in this section of drying wetland.
It took some time to arrange the writhing eel in a position where it could be swallowed.
The eel had no chance and is now beyond escape. 


Drying wetlands can be a rich source of food for a variety of water and other bird species and a place well worth spending time, especially if you get there just before dawn and watch the area light-up and come to life as the sun rises.

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