Saturday, June 23, 2012

Australia: An Afternoon at Coombabah

On the way back to Brisbane from Lamington, on April 8, 2011, the ladies dropped me off for a few hours' birding in very different habitat from the rainforests of the national park: the eucalypt woodlands and coastal mangroves of the Coombabah Lakelands Conservation Area on the southern edge of Moreton Bay. While they went off shopping, I had a very pleasant couple of hours on the excellent half-kilometre trail and mangrove boardwalk that lead to a bird hide on the edge of the reserve.

The short trail crosses four progressively wetter types of habitat as it descends to the hide: dry sclerophyll forest, swamp oak wetland with stands of casuarina, a band of saltmarsh marking the reach of the highest tides, and the mangroves themselves.

Eucalypts dominate the sclerophyll forest, including stands of Blackbutt (Eucalyptus pilularis or similar) - distinctive trees with rough bark sheathing the lower trunk that gives way, as if it had been stripped off, to smooth white bark higher up.

More widespread - because it penetrates into the swamp oak stands as well - is Queensland Grey Ironbark (Eucalyptus crebra).

One of the most striking plants of the swamp oak wetland is the Swamp Banksia (Banksia robur), whose large coarse leaves are very different from the narrower fronds of the banksias I photographed in the heathland south of Sydney.

Matrushes (Lomandra spp.) may look rather like coarse grasses, but they are actually relatives of asparagus and the Cordyline trees we saw in New Zealand. They are important components of the undergrowth in the sclerophyll woodland.  Aboriginals used the fibrous leaves to weave baskets and dilly bags (a sort of carry-all handbag).

The upper photo shows a clump of brilliant orange fungus that I cannot identify. I am not even sure if the bottom picture shows a fungus, but I think it does.

This huge mass of elkhorn fern (Platycerium bifurcatum) looks
several sizes too large for the tree it sits on. I am more used to seeing ferns like these on the trunks of rainforest giants. They always look to me as if they had been glued to their supports, but instead they are held in place by a series of rhizomes, invisible beneath the basal leaves. Under these plate-like, sterile fronds plant matter collects and decays, creating a little compost pile that nourishes the plant. The long, hanging fronds are fertile, and bear the fern's spores.

The ferns on the forest floor were rather more typical.  The one on the right could be Australian Bracken (Pteridium esculentum).

Among the birds I found in the sclerophyll woodland was a furtive group of Brown Pigeons (Macropygia phasianella). The Brown Pigron is the only Australian representative of its genus; the others, a group of forest-dwelling pigeons collectively known as cuckoo-doves, range from New Guinea to tropical Asia, and recent Australian bird guides call this one, too, the Brown Cuckoo-Dove. The name refers to their long tails, which give the birds a vaguely cuckoo-like profile. 

  The Silvereyes (Zosterops lateralis) were considerably less shy. Silvereyes are the most widespread of Australia's white-eyes, a group now known to belong to the babbler assemblage. They are inquisitive, active and altogether delightful little birds. 

Once the trail hits the tide line, it gives way to a boardwalk traversing the mangrove forest.

Australia has, I was surprised to learn, the third largest area of mangroves in the world, exceeded only by Indonesia and Brazil. Mangroves reach as far south as Victoria, their furthest extension anywhere into the temperate zone.   This appears to be Stilt Mangrove (Rhizophora stylosa), a species that elevates itself above the mud on stilt roots.

The mud is studded with the aerial roots, or pneumatophores, of the widespread Grey Mangrove (Avicennia marina).  The various plants called "mangrove" are often only distantly related, with quite separate adaptations for surviving in the salt-laden, oxygen-starved mud where they grow.  In Avicennia the pneumatophores are the lungs of the plant, involved in gas exchange with the surrounding air.

Where there is water, there are likely to be water birds: in this case, a pair of Australian White Ibis (Threskiornis molucca)...

...and a Royal Spoonbill (Platalea regia).

In the mangroves I found a few curious Grey Fantails (Rhipidura fuliginosa)...

... and a handsome male Leaden Flycatcher (Myiagra rubecula), a member of the monarch family (Monarchidae). The Leaden is a migrant in southeastern Australia, so this might be a bird on passage. 

In any case, he was extremely cooperative!

I enjoyed the trail so much that when Mui Ling, Alicia, Sue and Eileen came by to pick me up I insisted that they should see it for themselves. In particular, I wanted to show them a bird I had just found - one that even a non-birder could be amazed at. 

I had tried to turn up a Tawny Frogmouth (Podargus strigoides) at Lamington without success, so I was delighted to find this one, sitting quietly on a limb waiting for darkness to fall (the bright red eyeshine is a reflection from my flash unit, not the way its eyes normally look by day). Frogmouths are weird and striking creatures, looking rather like badly-drawn owls (though they are in fact nightjar relatives). I have sought the Tawny's Malaysian relatives in vain, so despite my Asian birding experiences this was the first wild frogmouth I had seen in many a year. The ladies were suitably impressed.

They were impressed even more, I admit, by the glorious sunset over Moreton Bay, from the bird hide at the end of the trail. I can't really blame them for that, can I?

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