About Me

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I've been a Canberran since moving here from Adelaide on the first day of 1980. I now live in suburban Duffy with my partner Louise Maher, ABC 666 radio and on-line journalist. Among my early memories is following Sleepy Lizards (Shinglebacks) around the paddocks north of Adelaide, guarded by the faithful bull terrier. I have always been passionate about the natural world, trying to understand how it works, how the nature of Australia came to be, and sharing those understandings. My especial passions are birds, orchids and mammals. For much of my life I have been a full-time naturalist, running bush tours, writing books etc, doing consultancies, presenting a regular radio slot on local ABC, chairing a government environment advisory committee and running adult education classes. Recently I have eased back somewhat, but am still writing, teaching, doing some radio work and running overseas tours - as part of my fascination with our Gondwanan origins I've been running tours to South America for the past decade. I was awarded the Australian Plants Society Award in 2001 and the Australian Natural History Medallion in 2006, both for services to education and conservation. In January 2018 I was awarded a Medal of the Order of Australia for 'service to conservation and the environment'.

Thursday, 14 June 2018

Bundjalung National Park; great name, great park

Recently we undertook a very pleasant meander through a series of national parks in north-eastern New South Wales (NSW hereafter), not much more than a good day's drive from home, exploring both the wet forest hinterland (including elements of the Gondwana Rainforests of Australia World Heritage Area) and the coastal heaths and forests. In the process we visited some 27 national parks, though most of these were of course fairly fleetingly; we saw it as a reconnaissance for future exploration. In others however we camped for a couple of nights, including Bundjalung, which I'd like to introduce to you today. In forthcoming postings I'll present a couple of the rainforest parks.
Black Rock Beach, Bundjalung NP, immediately behind the campground of the same name where we stayed.
More about the unusually coloured rock formations shortly.
Today the fairly modestly-sized 21,000 hectare Bundjalung, together with the smaller Broadwater NP to the north and the larger Yuraygir NP to the south, protects a substantial stretch of coastline, well over 100km long (though they are not quite contiguous). If you've driven along the north coast you'll know that much of it comprises a ribbon development of resorts, retirement complexes and giant bananas, so protected coast and the vegetation behind it is a very valuable asset indeed.
Bundjalung National Park, at the end of the red arrow, is on the far north coast of NSW,
not far from the Queensland border. It protects 37km of wild coastline, between Evans Head and the
mouth of the Evans River in the north, and Iluka and the Clarence River mouth in the south.
Black Rock campground, in the centre of the park, is larger than we feel comfortable with. (Well, to be truthful we'd much rather camp somewhere remote enough so there's no evidence of other people at all. That can often be managed inland in Australia, but is unrealistic and probably elitist near the populous coast, especially in national parks.) Furthermore we made the mistake of being there on a weekend when it was particularly busy. However the campground is well-designed, so that individual sites are tucked into bays in coastal shrubland, giving fairly good privacy from neighbours. There are basic toilets, though probably insufficient for a busy weekend, good information boards and walking tracks leading from the camp. (There is also a campground at Woody Head at the southern end of the park, but seems more like a resort/caravan park, and not somewhere we'd ever choose to stay. It seems to have been tendered out.) 
Part of our camp site, looking outward to the road. The clothesline is a nice and unexpected touch,
but was probably a bit superfluous given the double fence line along three sides of the site!
The nearest neighbours were out of sight behind the shrubbery to the left.
The system for determining which parks in NSW charge entrance fees ($8 per vehicle per day, when applicable) seems utterly random. You do pay at Bundjalung for instance, which offers minimal visitor facilities, but do not at Dorrigo (on the edge of the tableland not far away), which has extensive and excellent facilities. Camping (which at Bundjalung must be pre-booked) is another $24 a night for two people. I don't blame the parks service for this at all - they are constant pressure from government to make parks 'pay for themselves' and there is ever-decreasing government support for them, financially and politically.

OK, back to the park itself! This isn't pretending to be an overall coverage of the park - I can only comment on the areas we saw - but it should give you a reasonable overview. Firstly of course there's the beach, all 37k of it.
Black Rock Beach again. The eponymous black rocks, 'coffee rocks', were laid down in a rich swamp
during the Pleistocene (ie the past 1.6 million years). The silty material, rich in dark organic particles,
was later compressed into soft rock by developing sand dunes.
Behind the dunes are swathes of lovely heathland, alight with banksia flower when we were there.
Heathland near the campground.
Wallum Banksia B. aemula; wallum is an indigenous word from south-east Queensland,
used now to describe the coastal heathland habitat. It is found from just north of
Sydney to Fraser Island.

Coastal Banksia B. integrifolia is found along the entire east coast; we also saw a form
growing to a fair-sized tree in mountain rainforests.

Heath-leafed Banksia B. ericifolia grows along much of the NSW coast in sandy soils.
Guinea Flower Hibbertia sp., family Dillenaceae.
Both this species and the next belong to extensive genera, and I couldn't get them down to a species.
Goodenia sp., Family Goodeniaceae.
Another significant habitat, though less extensive, is that dominated by paperbarks, especially Broad-leaved Paperbark Melaleuca quinquenervia. These forests grow mostly along streamlines and in boggy areas that are regularly inundated.
Broad-leafed Paperbark along Jerusalem Creek, on a walking track near the camp.
And in the far south of the park, around Iluka, is a most unexpected habitat indeed, for here, growing on sand, is a rare and precious remnant of littoral (ie coastal) warm temperate rainforest.
Warm temperate littoral rainforest, Iluka.
In 1964 the government was preparing to allow sand miners (a scourge of coastal conservation in Australia
at the time, notably on Fraser Island) to destroy this remnant, often described as the best remaining example in NSW.
Community reaction was intense and the government backed off. In 1976 Iluka Nature Reserve was gazetted.
In 1980 the much bigger Bundjalung NP was declared to complement it; this was a relative golden age of conservation
and park declaration in NSW. (Relative certainly to today, better described as a rusting scrap metal age...)

Lianas in the sandy understorey.

The canopy trees are primarily Riberry Syzygium luehmannii and
Broad-leafed Lilly Pilly Syzygium (formerly Acmena) hemilamprum.

Strangler Fig Ficus watkisoniana.
The busyness of the campground and surrounds certainly mitigated against optimal wildlife viewing, but there was a still a range of animals to be seen in the immediate vicinity of our camp.
White-cheeked Honeyeater Phylidonyris niger in early pre-sunrise light, surveying her domain.
These heath specialists are ubiquitous in the heaths of central eastern Australia. They also have two
discrete far-flung populations, one in the heaths of south-western Australia, and one in wet mountain
forests of tropical north Queensland.
Any east coast campground is likely to have a coterie of big Lace Monitors Varanus varius patrolling
in the hope of hand-outs or scavenging opportunities. Black Rock is no exception.

One of the camp goannas showing off his/her forked tongue with which they constantly 'taste' the air
to assess the environment. For more on these fascinating big lizards, see here.
These much smaller but much more dangerous animals were right in our camp site,
requiring us to be very wary indeed. The sting of Bull Ants Myrmecia spp. is excruciating.
They are among the most primitive of ants; in Australia at least more modern ants have 'disarmed',
losing their chemical weapons. Perhaps we could learn from them.
A much more benign visitor dropped by very late on our last evening there, as the light was going.
Swamp Wallaby Wallabia bicolor.
However our best wildlife viewing came in a small patch of paperbarks along the Jerusalem Creek walking track, not far from camp. It was bustling!
The scene of the action! This was mid-morning too, well outside the expected peak time of activity.
Here are some of the animals (mostly birds) which kept our heads spinning.
A very curious female Mistletoebird Dicaeum hirundicum, one of several in the area.

The males were a bit more circumspect; this one is performing his crucial ecological role of
distributing mistletoe seeds to other sites on tree branches.
Black-faced Cuckoo-shrike Coracina novaehollandiae; a widespread and common enough
bird, but when was that a barrier to enjoying one? And who knows, this may have been
one I saw in Canberra before it migrated north for winter. And all the same comments
could be made about the next bird too.
Noisy Friarbird Philemon corniculatus, a big (and yes, noisy) honeyeater.
The pale scallops on the back tell us that this is a young bird, from last spring's nesting.
This honeyeater on the other hand is one we don't see in Canberra.
 White-throated Honeyeaters Melithreptus albogularis are found north from about here and
right across tropical northern Australia.
Male Rufous Whistler Pachycephala rufiventris; this one too is a summer breeding migrant to Canberra.
The one that gave me the most satisfaction out of this lovely little flock was however on the ground. I have never managed to lay lens on a Brown Quail Coturnix ypsilophora before, though I've glimpsed them many times (usually vanishing like little dumpy rockets). This pair however were extraordinarily obliging.
And when you see them well like these, they really are a very beautifully marked little bird.
And in between, we were able to enjoy a most beautiful butterfly, one with which I was not familiar.
Blue Tiger Tirumala hamata; it too was much more accommodating than I've learnt to expect butterflies to be.
We came back late in the afternoon to indulge ourselves in some more birds and whatever else was about - and of course the entire grove was deserted. Bird-watching can be like life sometimes.

I'll talk about a couple of the other parks we spent time in too, in the not too distant future, but meantime I hope I've persuaded you that Bundjalung is definitely worth a day or so of your time.

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Thursday, 31 May 2018

Spreading the Seeds; animals 'helping' plants

I was reading an intriguing story yesterday - which I'll get to shortly - which led me to think about animals being 'employed' by plants to distribute seeds. There are various ways of doing this, including by sticky burrs which cling to fur and feathers, eventually being dropped (or releasing the seed) some distance from the start of the journey. 
Bidgee Widgee burrs, Acaena novaezelandiae, Family Rosaceae, hitching a ride on my boot laces,
alpine zone, Kosciuszko National Park. They'd probably prefer a wombat or wallaby, but I'll do!
Daisies are another family to employ this strategy.
Australia has perhaps the richest ant fauna in the world, so it is unsurprising that plants from a wide range of Australian families have employed them to assist in distributing seeds. Obviously they don't want the ants to break the seeds up and eat them, and in fact the seeds are usually too hard for the ants to eat. Instead the plant attaches a nutritious temptation to the seed, which the ants haul off to the nest, detaching the seed when they get there and leaving it on the surface or in an underground garbage dump. This dry attachment is either an aril (if it derives from the seed attachment) or an elaiosome (a fatty body different from the aril), and is smaller than the seed. Ants have been observed carrying such seeds up to 75 metres from where they found them.
Discarded seeds surrounding an ant nest, near Alice Springs, central Australia.
But does it work? It certainly does!
Seedlings sprouting from ant nest, Great Sandy Desert, Western Australia.
Ants don't seem to pay much attention to colour, so these arils and elaiosomes tend to be pale in colour. However some acacias have colourful (especially red) arils, which are displayed high on the plant for birds to gather - again taking the seeds along with it.
Blackwood Wattle Acacia melanoxylon, pods, Namadgi NP, near Canberra.
Overall however the simplest and most effective strategy is to have the seeds eaten by a large mobile animal and discarded elsewhere, in droppings or perhaps as regurgitate. Energy is a very important resource - and temptation - for animals, which of course is why so many plants wrap their seeds in colourful, sugar-filled fruits, constructed from the wall of the fertilised ovary. The hard seed passes through the body, deposited sometimes many kilometres away. Here are some birds caught in the act!

Double-eyed Fig Parrot Cyclopsitta diophthalma eating figs (of course), Cairns Esplanade, Queensland.

Metallic Starlings Aplonis metallica eating palm fruit, Cairns Botanic Gardens, Queensland.

Silvereye Zosterops lateralis, with heath berries, Family Ericaceae (or Epacridaceae),
Australian National Botanic Gardens, Canberra.

Pied Currawong Strepera graculina eating Cotoneaster sp. berries, suburban Canberra.
These hedges (and related Pyrocantha spp.) are widely planted in older Canberra suburbs, and currawongs
are important distributors of the seeds into nearby nature reserves, where they are a serious weed hazard.

Male Mistletoebird Dicaeum hirundicum with mistletoe seed, Bundjalung NP, New South Wales north coast.
Mistletoebirds live almost exclusively on mistletoe berries, and are the major vector of the seeds.
It is a fascinating story, and will have its own post one day.
In rainforests in particular, birds and fruit bats are very important vectors of the whole forests' seeds - trees, lianas and shrubs. 

Rose-crowned Fruit Dove Ptilinopus regina in fig, Kakadu NP, Northern Territory.
Other key bird groups involved in distributing rainforest seeds in Australia include bowerbirds
and orioles (which include the figbirds).


Another important contributor is Australia's second-largest bird.
Southern Cassowary Casuarius casuarius, Atherton Tableland, northern Queensland.
We now know that the seeds of the Javan Ash Ryparosa kurrangii, a rainforest tree from north Queensland, germinate far better if they've passed through a cassowary. In fact, over 90% of seeds taken from cassowary droppings germinated, compared with only 4% of uneaten seeds. It has long been known that cassowaries are important vectors of rainforest seeds, but this adds another dimension to their value in the rainforest ecosystem. (The researchers also incidentally found that Javan Ash seeds have one of the highest levels of cyanogens ever recorded in a plant, but presumably the birds pass them through quickly enough and without breaking the surface of the seed, so that they are unaffected.)
In rainforests elsewhere in the world, other birds perform similar roles.
Yellow-throated (or Black-mandibled) Toucan Ramphastos ambiguus, with cecropia fruit,
Wild Sumaco Lodge, northern Ecuador.

Grass-green Tanager Chlorornis riefferii, Abra Patricia Lodge, northern Peru.
Red-crowned Barbet Psilopogon rafflesii, Bako NP, Sarawak.
Bats must never be underestimated however, despite doing their valuable work under cover of darkness.
Black Fruit Bats Pteropus alecto, Charters Towers, Queensland.
Big bats like this - with wing spans of more than a metre - travel many kilometres in a night,
visiting distant rainforest remnants. Smaller seeds are ingested, but even larger ones can be carried
for several minutes before being spat out.
They are not the only mammals to perform the task however.

Ecuadorian Squirrel Monkey Saimiri macrodon (or Saimiri sciureus macrodon), Yasuní NP, Ecuador.
Seedlings sprouting from elephant dropping, Kibale NP, Uganda.
Some plants have even secondarily 'invented' fruit by causing the stem immediately below the bare terminal seed to swell, turn red or black, and fill with sugars, for the same reason as other plants develop 'real' fruit.
Dwarf Ballart Exocarpos strictus.The red 'fruit' is the pedicel, or flower stem, the real fruit is the hard dark nut below it,
comprising a seed in a hard casing.
Mountain Plum Pine Podocarpus lawrencei, Namadgi NP near Canberra.
This is a conifer, so clearly cannot have true fruit (which, as explained earlier, must develop from a flower).
Again the pedicel is swollen, coloured and sweet, and the seed sits on top of it.
Which is pretty much the story - except that I mentioned at the start something I read which triggered this. It was a study conducted by Japanese ecologists which implied that at least one group of animals might have adopted a similar strategy to distribute their 'seeds' - which are really eggs. Stick insects, or phasmids, are poor distributors - many are flightless - but occur on many islands. 
Titan Stick Insect Acrophylla titan, Nowra, south coast NSW.
This one can grow to 25cm long.
Moreover, many species can reproduce parthogenetically - ie without mating. In this case all the hatchlings are female; if they mate both males and females result. The scientists presumably wondered about these two things, because they tried feeding eggs of three phasmid species to Brown-eared Bulbuls Hypsipetes amaurotis, a major phasmid predator in Japan. Up to 20% of the eggs survived, and some hatched, meaning that the birds could potentially be enabling the flightless insects to island-hop. Their next task is to compare the genetics of stick insects along known bird flight paths, to see if there is a correlation. A small thing, but surely much of life depends on a collation of small interesting things...
White-bellied Cuckooshrike Coracina papuensis with large (probably gravid female) phasmid, Nowra.
Did this bird do a favour to its lunch by sparing and spreading its eggs?
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