Mareeba Wetlands: sweeter than sugar

There is a constant tension in near-coastal Queensland between the sugar cane industry and reaction to its impacts on ever-dwindling natural tropical and sub-tropical habitat, from rainforest to savanna woodland. Mareeba, inland from Cairns, is not on the coastal strip where most sugar is grown, but in the early 1990s the industry was seeking new areas to expand as opportunities on the coastal strip became limited. An area north of Mareeba, on the escarpment plateau 400 metres above sea level, was earmarked as an option. It was an area of tropical savanna woodland, of a type quite widespread but not well protected in reserves. Most importantly however in the selection of the area for further cane growing, was the existence of the Mareeba-Dimbulah Irrigation Scheme, based on the Tinaroo Dam on the Atherton Tableland to the south. It supports a major fruit-growing industry and in the past a large tobacco crop, though this has become much less significant in recent years.

Mareeba is approximately at the end of the red arrow;
as can be seen it is well north of the Tropic of Capricorn.

Savanna woodland, Mareeba Wetlands Reserve.
Eucalypts and shrubs grow over a grassy understorey. Massive termite mounds reflect the
significance of a huge biomass of grass-harvesting termites to the local ecology.

The proposal was to open a new area to sugar cane utilising the run-off from water which had passed through the irrigation channels. This wasn't necessarily a problem in itself, but fortunately appropriate studies were required, and these studies determined that there were serious environmental constraints on that site relating to soil types and the potential for downstream salinisation issues. 

However a group of far-sighted locals saw the potential for creative alternative uses for both the water and the land, based on the knowledge gained through the existing research. They formed the Mareeba Wetland Foundation (which has since evolved into the Wildlife Conservancy of Tropical Queensland) to press for the creation of the Mareeba Tropical Savanna and Wetland Reserve. (It is still known to all and sundry as simply the Mareeba Wetlands so I'll continue to do so to.) They proposed a 2000 hectare savanna reserve featuring a series of gravity-fed ponds. One might argue that a wetland has no place in a savanna, but many natural wetlands have been drained, so I'd just see it as compensating for some of these. The loss of some woodland - well-represented locally - is balanced by the recreation of wetland and associated habitats which have been lost locally.

Their proposal was sufficiently well-researched and convincing to persuade the federally-funded Regional Infrastructure Development Program to support it, and local, state and commonwealth governments, as well as local business, especially the tourist industry, offered assistance. The reserve opened to the public in 1999. By then the wildlife had already offered its approval, and it had become one of the most significant Brolga and Sarus Crane roosts in north Queensland. A walk around the biggest lagoon is likely to be accompanied by the wonderful wild bugling of cranes drifting down from the sky.

Mareeba Wetlands, with the visitor information centre visible across Clancys Lagoon.
The walk around this lake, with the promise of coffee and treats at the little cafe at the end of it,
is a delightful introduction to the reserve.

The local Muluridgi people were granted title over the reserve in 2011, and the reserve is now operated as a partnership. All staff are volunteers. The magnificent visitors' centre was built with assistance from local industry.

A closer view of the Clancys Lagoon Visitors' Information Centre (VIC).

The VIC deck - an excellent location to enjoy the view and the wildlife (with or without coffee).

Another view from the deck.

There are several research and monitoring projects ongoing, including on the cranes and on the rare and little-understood Buff-breasted Buttonquail, but one very obvious one to the visitor is the captive breeding and release program for the glorious but seriously threatened Gouldian Finch.

The Gouldian Finch breeding aviary (above and below) backs on to the VIC, and faces the
wetlands and woodlands to which they are steadily being released.

The Gouldian Finch Erythrura gouldiae is truly an exquisite bird, named by the great 19th century
ornithologist John Gould for his wife and work partner, the artist Elizabeth Gould.
Once found throughout northern Australia, numbers have plummeted due to a complex of factors,
among which changed fire regimes seem likely to be the most significant.

 Waterbirds can be seen from the deck, though Clancys Lagoon is big and they will not necessarily be close.

Comb-crested Jacana Irediparra gallinacea from the VIC deck.
Its enormous toes for distributing its weight on the leaves can be seen in this photo.

The creek by the VIC entrance can be excellent for frogs, including one of my favourites.

The White-lipped Tree Frog Litoria infrafrenata is reputedly the world's largest tree frog - it can be close to 14cm long.
It is found in north Queensland and beyond into New Guinea and associated islands.

Out in the woodland there are many resources for wildlife, including flowers and grasses.

Broad-leaved Paperbark Melaleuca viridiflora is found across northern Australia.
The species name is from these (sort of) greenish flowers, but unfortunately they are just as likely to be red!

Thysanotus juncifolius, one of the glorious fringe-lilies.

Native Rice Oryza australis; the seeds are tiny but prolific and feed many animals.

Such grasses support several finch species, among others.

Black-throated Finches Poephila cincta (a declining species, above) and
Chestnut-breasted Manikins Lonchura castaneothorax harvest the reserve's grass seeds.

 

Pheasant Coucal Centropus phasianinus, a wonderfully scruffy and shambling big bird.
Throughout the world 60% of cuckoo species actually nest and raise their own chicks in the
conventional way, but in Australia this is the only one to do so.

Squatter Pigeon Geophaps scripta, a striking tropical ground-dwelling pigeon.

Male Leaden Flycatcher Myiagra rubecula, a monarch flycatcher.
This species migrates between the tropics and south-eastern Australia, where it breeds.
I might even have seen this bird in Canberra!

But as is the way in Australian tropical savannas, reptiles are almost as obvious as, and probably more abundant than, the birds.

Tommy Roundhead  Diporiphora australis on a Mareeba termite mound.
Australia has the most diverse arid land lizard fauna in the world, and the basis
of this proliferation is the huge mass of termites.

Snake-eyed Skink Cryptoblepharus virgatus; another who doubtless dines on the termite smorgasbord.

And finally, one of the most exciting things I've seen, in that I've looked for it in vain for many years (most recently in Kakadu NP in summer, supposedly the best place and time to look). The spectacular big Frill-necked Lizard Chlamydosaurus kingii has normally gone into winter torpor in a tree by May, when I was last there. Our luck was in however as this beautiful beast was awake and just outside the VIC.

The only member of their genus, they can grow to nearly 90cm long, and this was a big one.
The loose frill can be erected into a fearsome ruff if the owner feels the need to protect itself,
but this lovely obviously wasn't too stressed by our presence.

I can't guarantee you'll see a Frilly if you go to Mareeba Wetlands - though you certainly won't see this one if you don't go! - but I can guarantee you'll see a rich and beautiful part of Australia, and you'll see what can be done if enough people use their imagination, initiative and determination to make things better.

Next time you're up that way, don't miss it!

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Proteaceae; the form-changers from Gondwana

I thought it was time to write something more Australian than I've done recently, and it being gloriously spring here at last (and unsurprisingly, with each year spring becomes more precious) flowers seemed an appropriate topic. For no especial reason I thought of the lovely and diverse Grevilleas as a topic, but when I started planning the post I realised that we needed a bit more context, so felt obliged to start with the wider family, the wonderful Proteaceae. (There's probably a name for a brain that obliges me to be so structured, but it doesn't matter because that's the only one I've got, or am likely to have.)

The family is essentially Gondwanan and old one, centred on Australia but represented strongly in southern Africa and to a lesser extent in South America, India, New Caledonia and New Zealand. It has spread north into Africa, into Indonesia and south-east Asia, and into central America and Mexico. There are some 1700 species in about 80 genera; of these 1100 species and 46 genera are Australian.

Woolly Grevillea G. lanigera Namadgi NP near Canberra.
This is the largest genus with some 360 species, virtually all Australian.
The typical Proteaceae flower - though no single statement is likely to be universally true in such a
diverse family - has four tepals (the term used for petals and sepals which can't be reliably
defined as one or the other) with a style which first bears pollen and later receives it.

Notro or Firebush Embothrium concinnum, Torres del Paine NP, southern Chile.
A small but spectacular South American genus whose close relationship with the
Australian waratahs (Telopea) is evident.

Protea nitida near Cape Town - a scan of a somewhat faded old slide.
There are nearly as many Protea species as there are of Grevilleas.
This is the genus from which the family takes its name - in other words it was the first
genus in the family to be named. The great Linnaeus named it for the Greek god of that name,
noted for having many shapes. That description is appropriate for the entire family too,
but despite some assertions that was not why the family was named!

The Gondwanan distribution has generally been taken at face value - ie evidence of an ancient group which was present when the southern continents went their own way. Recent molecular dating work (eg DNA sequence research), especially involving Dr Peter Weston of the New South Wales Herbarium, suggests that, counter-intuitively, the various groups dispersed outward from Australia at different times to colonise the rest of their current range by oceanic drift. (A similar result was recently suggested too by research into the ratites - the giant flightless southern birds - suggesting that they must all have flown to their current sites across the southern hemisphere and then all independently lost the power of flight.) All things are of course possible, and I claim no expertise, but both these scenarios seem remarkable to say the least, when compared with the more obvious traditional explanations. I wonder if there is more to be said on this.

Proteaceous plants can be trees, big shrubs, sprawling ground covers and even, in some cases, herbs. In addition to the characteristics noted above under the Grevillea photo, in many species the anthers are attached to the inside of the floral tube. The tip of the style, the stigma, is touching the pollen; as the style grows it puts pressure on the sides of the flower tube until it splits; at this stage the stigma springs out, still bearing the pollen which is taken by either insects or birds depending on the species. Shortly afterwards the stigma grows a brush and becomes a conventional pollen receptor. Flowers may be single, paired or in large spikes.

Grevillea pectinata near Salmon Gums, southern Western Australia.
The upper styles have emerged, the lower ones are still trapped in the flower tube.

Fruits are dry capsules opening to release just one large winged seed; the capsules may be embedded in a cone for species with large inflorescences; if single they may be hard, woody and fireproof or fragile and papery. Persoonias are exceptional in having fleshy fruit.

Banksia speciosa cone near Esperance, southern Western Australia.
Only a few of the numerous flowers are usually fertilised.

Recently burnt fruit of Mountain Devil Lambertia formosa, near Nowra, New South Wales.
The devil's head will soon split to drop the seed into the ash bed.

Hakea microcarpa fruit, Tidbinbilla Nature Reserve near Canberra.
Most Hakeas have thick woody cones, but this one has smaller more fragile ones;
Grevillea and Lomatia have even more papery fruits.

Persoonia sylvatica fruit, Tinderry Nature Reserve south-east of Canberra.

Another family characteristic (though again not univeral) is the presence of curious root structures called proteoid roots, which grow annually as short very dense masses of root hairs from the sides of normal roots. Their function is similar to that of mycorrhiza (fungal 'hairs' associated with a plant's roots) in other plants, providing a greatly increased root surface area to contact scarce soil nutrients and water. Proteaceae don't have mychorrhiza; the proteoid roots seem to have an association with soil bacteria.

Species are found from very arid central deserts to wet near-coastal forests.

Hakea lorea, Kata Tjuta NP, central Australia

Monga Waratah Telopea mongaensis, Monga NP, south-eastern New South Wales.

Most plant families have either vertebrate or invertebrate pollinators, but it is probably unsurprising that such a large family should have many strategies; mammals, birds and insects all have roles in different branches of Proteaceae.

Western Little Wattlebird Anthochaera chrysoptera on Banksia speciosa, Esperance, Western Australia

Native bee on Persoonia sp.
(Probably Xylocopa sp. - thanks Susan.)

Five subfamilies are recognised, all being present in Australia. 

Symphionematoideae comprises just three species in two genera; Symphionema in New South Wales and Agastyachys in Tasmania

Bellendenoideae has just one species, from the highlands of Tasmania.

Mountain Rocket Bellendena montana, Ben Lomond NP, Tasmania.
The flowers form white spikes in summer; these are the seed capsules.

Persoonoideae comprises five genera; four are very small and recent work suggests that three of them should properly be included in the best-known genus of the group, Persoonia.

Persoonia linifolia; the tepals have rolled back to expose the four anthers and central style.

Proteoideae is a bigger grouping, containing 25 genera including nearly all the African ones.

Stirlingia latifolia, Badgingarra NR, north of Perth.
Commonly known as Blue Boy because cement made from the sand it grows in turns blue!
Stirlingia has just seven species, all from Western Australia.

Conospermum distichum, Cape le Grande NP, south-west Western Australia.
Members of the genus are known as smoke-bushes, as they grow en masse
on heathy sandplains, causing the landscape to appear hazy.
Fifty species are found across southern Australia.

Isopogon divergens Kalbarri NP, Western Australia.
(My thanks to Phil Trickett and Catriona Bate for identifying this beauty for me.)
Often known as drumsticks for their globular seed cases, the 35 species are found across Australia,
though most are in the west.

Petrophile pedunculata cones, Nowra, New South Wales.
These are generally called conesticks from their more elongate woody fruits.
There are some 70 species, again mostly in the west.

Adenanthos terminalis Heggarton Conservation Park, Eyre Peninsula, South Australia.
The jugflowers or woolly-bushes are most atypical in the family, not least in having just
one flower in the inflorescence.
This species from the South Australian mallee, and one from Victoria, are the only
two of the thirty species not restricted to Western Australia.

Grevilleoideae contains the 'big three' Australian genera, plus most of the Australian rainforest species, the Malesian species, and the American ones.

Grevillea juncifolia, central Australia.
A spectacular desert-dwelling member of the biggest genus (370 species, nearly all being Australian).
And it will get its own posting in the not too distant future...

Massed Banksia menziesii (red) and M. hookeri, Lake Logue NR, north of Perth.
Banksia inflorescences can have thousands of individual flowers and are immensely
attractive to mammals, birds and insects.
They too warrant their own posting, not least because there are 170 species, but...

Dryandra formosa near Albany, Western Australia.
In 2007 this large genus was absorbed into Bankia based on evidence that appeared to me comprehensive at the time but has by no means been accepted by authorities much more qualified than I, including the Dryandra Study Group of the Australian Native Plants Society, and eminent West Australian botanist Alex George.
Since publishing this post I have been sent Alex's article challenging the change, and I find his arguments compelling.
For those who do accept this radical change, it more than doubles the number of Banksia species, including this
species which would be known as Banksia formosa.

Hakea multilineata near Norseman, inland southern Western Australia.
There are 150 Hakea, found throughout Australia, though again concentrated in the west.
The similarities with Grevillea may not be coincidental - there are rumblings that suggest there
may soon be over 500 Grevilleas and no Hakeas!

Lomatia polymorpha, Mount Field NP, Tasmania.
This genus of 12 species is found on the Pacific sides of both Australia and South America.

Lomatia hirsuta, Volcano Orsono near Puerto Montt, southern Chile.

Lambertia formosa Nowra, New South Wales.
These flowers produce the Mountain Devil fruit pictured above.
This is the only eastern species, but well known; there are another nine in the west,
where they are widely known as honeysuckles.

Woody Pear Xylomelum angustifolium fruit, Lake Logue NR, north of Perth.
A striking small tree, and an unusual genus in this context in that there are more species
in the east (four) than in the west (two).

Orites lancifolia, high Namadgi National Park, above Canberra.
In addition to the seven Australian species (most of which are Tasmanian) there are two in South America.

Well, if you're still reading after all this - thank you! I hope it's been worth it. As noted, there will be postings on two or three of these genera in the future but for now that's enough! If you can go and see some actually growing now, so much the better.

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