Thursday 14 July 2016

East Point Reserve, Darwin

From Canberra in winter, lovely tropical Darwin always seems attractive. And so it does today as I write this. If you are fortunate enough to be visiting there some time in the nearish future, and you're interested enough in nature to be reading this blog, you should really aim to put aside at least a couple of hours to visit East Point Reserve. Probably all the locals know it, but it's certainly not on every visitor's schedule, and those who do find their way there are probably looking for the historical aspects associated with World War 2 fortifications. Today however I'd rather try to lure you to its natural charms. Because of its recreational popularity it's easy to find, so I won't try to give you detailed directions here. It's a peninsula that represents the eastern-most point of Darwin Harbour (the west side of the harbour, well outside the city, doesn't appear on the map below).
East Point Reserve, indicated by the red arrow, protruding into the Timor Sea.
As is evident it is well within suburbia, and not far to the north of the city of Darwin.
While it's all interesting, much of it comprises open mowed grassy areas with scattered trees, and the two elements I want to focus on today are the mangrove board walk (as far as I know, still the only such public boardwalk in mangroves in the Northern Territory!), and an extensive area of monsoon forest. 

You reach the mangroves first; pull into the Lake Alexander carpark, near the start of the reserve, and there is a sign to mark the beginning of the walk, which begins through low monsoon forest and coastal scrub before entering the mangroves.
Low monsoon forest on the way to the mangroves; I'll leave an introduction to the habitat until a little
later, when we get to the more substantial area of it.
The strip of mangrove forest grows along the northern shore of the narrow peninsula which we've just walked across from the southern side. There are 11 mangrove species found here, which is not very rich by the standards of larger sites, but impressive nonetheless. The raised aluminium walkway through the tidal section - the tide can rise by more than five metres here - is impressive and makes for an excellent mangrove experience.
Part of the aluminium walkway at low tide; this wide section at the end of the walkway, with benches,
is an excellent place to sit and watch what comes by.
We did just that for quite some time from early morning one day last summer.

The view in the other direction, looking out to the sea through the trees.
The ground is covered with pneumatophores, woody root extensions which protrude from the mud
to enable respiration in a waterlogged environment.
These mangroves are mostly White-flowered Apple Mangrove Sonneratia alba, family Lyrthaceae.
This species has a huge range, from East Africa across southern Asia and Indonesia to the West Pacific.

White-flowered Apple Mangrove flower. It's important to realise that 'mangrove' isn't a taxonomic term;
it can be used for any tree which has adapted to growing in regularly inundated salt-saturated mud of the inter-tidal zone.
In fact in Australia alone there are 41 species of mangrove, representing 19 different families. Some of these
mostly comprise mangroves, others are familiar terrestrial plant families.

Red, or Stilted, Mangrove Rhizophora stylosa, family Rhizophoraceae, found widely in Australia and Indonesia.
This is the other dominant mangrove at East Point, and demonstrates another type of pneumatophore,
the stilt root, which grows down from the stem and then branches, providing both support and respiration function.
I am not going to delve any more deeply into mangrove biology here - it's a fascinating topic which deserves, and will get, its own post one day.

It was a relatively quiet morning for wildlife when we were there, but there's always something, starting as soon as we left the carpark.
The extraordinary Magpie Goose Anseranas semipalmata is common across tropical Australia
and adjacent New Guinea. It is the sole member of an entire family of waterfowl
(ie 'ducks and geese', though it is neither).
Bar-shouldered Doves Geopelia humeralis are also very common, but that's no reason not
to enjoy and share them, especially as I know that many readers come to this blog from elsewhere.
They have an endearing habit of warbling repeatedly in a falsetto voice "let's walk to schoooool".
Rainbow Bee-eaters Merops ornatus against the morning sun.
Our only bee-eater, and an impressive one. They breed in southern Australia and spend
the rest of the year in tropical Australia, New Guinea and nearby Indonesia.
However even in summer there are always some in the north as well.
Male Australasian Figbird Sphecotheres vieilloti. Yet another common northern species, actually an oriole.
This used to be called the Yellow Figbird, to distinguish it from the Green Figbird further south in eastern Australia,
but they are now regarded as races of the same species.
As we sat among the mangroves at the end of the walk a few birds came to investigate.
Northern Fantail Rhipidura rufiventris. Two fantails are among the commonest birds further south,
but this tropical species, while certainly not rare, is less obvious than them.

Lemon-bellied Flycatcher Microeca flavigaster.  A lovely little bird, one of the Australian robins; for that
reason, probably understandably enough, there is a move to resurrect the old name of 'flyrobin', but I'm not
quite ready for that yet.
Not many waders on the mud, but our view was pretty limited. The Common Sandpiper Actitis hypoleucos isn't that common in southern Australia, though more so in the north. This one was snacking on the abundant crabs.
Common Sandpiper with seafood breakfast.
Crabs are of course super-abundant in mangroves, living in burrows and supporting numerous predators,
including this gorgeous blue chap, which I unfortunately can't find a name for. Any help?
Another favourite mud-dweller, the wonderful mudskippers, regarded traditionally as a subfamily
of goby, though recent work suggests they actually comprise several related groups. Their key characteristic is an ability
to spend much of their time out of water, being quite active across the surface of the mud, using their adapted fins.
As long as they remain moist they can breathe through skin and mouth membranes on land,
as well as with gills in water.
Gill slits are tightly closed on  land, and the cavity contains an air bubble.
I like to think of them re-enacting the first vertebrate moves ashore nearly 400 million years ago.

When you can tear yourself away from the peace of the mangrove platform, return to the carpark and drive a little further along the road into the reserve. Just past Peewee Restaurant (and I'm afraid I can't tell you anything else about it, I've always been there too early!) pull into the carpark marked Barbecue Area and cross the road to the track opposite through the monsoon forest. 
Monsoon forest along the track. Monsoon forests grow in the tropics where an intense wet season is
followed by a long dry, which distinguishes them from true rainforest where it can be wet all year round.
They tend to be lower-growing and simpler in biodiversity (though by no means impoverished) than rainforests;
many trees are often deciduous in the dry.
Two special birds in particular can generally be found here. In fact you're likely to encounter Orange-footed Scrubfowl Megapodius reinwardt pretty much any time from when you enter the forest.
Orange-footed Scrubfowl scratching for food in the leaf litter on the track with its immensely powerful feet.
(Which, I must note, are not more orange than its legs.)
This is one of three Australian megapodes, which incubate eggs in a mound of decomposing litter.
This one alone is found beyond Australia, on nearby islands.
Scrubfowl mound, Darwin; for a relatively small megapode they build an enormous mound.
Pittas are an interesting group of birds, members of the ancient suboscine passerines which predominate in South America but are scarce elsewhere. There are three Australian species - the Noisy Pitta Pitta versicolor of eastern Australia, the Rainbow Pitta P. iris of the Top End and Kimberley, and the Red-bellied Pitta Erythropitta erythrogaster which breeds at the tip of Cape York Peninsula in Queensland in the wet summer, and returns to New Guinea for the rest of the year.

The Rainbow Pitta is not uncommon in monsoon forest around and even in Darwin, and East Point Reserve is a good place for them, though they are shy and can take some finding. They feed on the ground but often call from a high perch. Their call is a constant background at East Point.
Rainbow Pitta, East Point. Truly a beautiful bird.
If East Point isn't already on your 'to do' list when you go to Darwin, it should be. Try and make time for it - you won't regret it.

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2 comments:

  1. Hi Ian, I was led to your blog by a friend who sadly for him remains in freezing Canberra. As it turns out, I was but a few km from the walk so I went there for a look-see. It's a nice little walk out to the end of the boardwalk, one that i didn't know was there. The tide was well out at the time so I saw very little except one crab scuttling back into its hole, and my wife snapped one of this pretty little flycatchers
    cheers, brian

    ReplyDelete
  2. Hi Brian, and good to hear from you - even better that I've managed to do you a service! Sorry it's taken so long to reply but I'm only just back from 3 weeks bird surveying in the Western Deserts. Hope your trip continues well!

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