21 August 2009

Top End - Part 2

Once we had got properly acquainted with our camper van we headed for one of this trip's 'must see' destinations, Kakadu National Park.

To understand Kakadu it is necessary for me to explain the climate. We were there in The Dry, which makes it look like a sensible piece of land. In The Wet rain falls in torrents for months on end and more water runs off the escarpment drowning huge areas of floodplain. At Yellow Water we were shown the park ranger's mooring. It is a floating jetty attached to pillars about 4m high. During the Big Wet a few years ago the jetty floated clear off the top of the pillars and was recovered 3km away. Even in a valley this would be impressive, but plain here is several kilometers across. That's a lot of water!

During The Wet vast tracts are accessible to water creatures. Maturing barramundi (a favoured sport and eating fish) swim down to the sea and spawn in the mangroves. Later their fry swim back up into fresh water for the first few years of their lives. Also, estuarine crocodiles ("salties") swim up from the sea and can get virtually anywhere.

When it stops raining the fresh water runs off in to the sea and the water levels start dropping. In time, there is enough dry land that a freshwater sea with a little high ground has become a landscape with conventional rivers, lagoons and billabongs. The fish, frogs, turtles and crocodiles crowd into these restricted areas. Eventually some of them dry out entirely, which is bad luck on the baby barramundi. The turtles can bury themselves in the mud and the frogs probably do the same. The crocs eventually figure out that they are marooned and set off across country. Most of them make it to permanent water.

We were there in the middle of The Dry, when most of the temporary water had already gone. The last Wet was a very modest one, with half the normal rainfall.

The Aboriginal folk sub-classify the year into six seasons. To read about this click here and use the link to Climate. Note that the indigenous people regard August as the "cold" season, when we were only getting up to 35C in the shade.

OK, now you know how Kakadu works.

At our first stop in the national park we had a good view of the general principles at the Mamulaka wetlands. Here was a lavish permanent hide and marshes into the distance with hundreds of birds. Due to the contrariness of the birds and the angle of the sun, very few of them were suitable for a photo.

An egret paddling through the mud.

There was a well signposted bushwalk at the site. This took us past some helpful information boards and came close to some more marshy places, where hundreds of whistling ducks were enjoying some shade. We also learned about some of the trees:

This is a kapok blossom. It will become a seed pod, like the one above, that will ripen with seeds and teddy-bear stuffing!

Part of a pandanus seed cluster. The entire thing resembles a huge pineapple. The cockatoos can crack the individual seeds to get at the edible kernel.

No comments: