Tropical Diary: Tick Magnet

You can't blame them. Blood is a highly nutritious food. After all, it sustains thousands of vampires of both the black-cloaked and sparkling varieties.

But there's a dilemma with blood as a resource — it's the perennial problem of supply and demand. If novels and movies are to be believed — and we know that they are impeccable sources of information — one flamboyantly coiffured member of the Undead requires multiple similar-sized food sources to keep it going. That would be sustainable if the population of hosts far exceeded the population of haemovores. But vampirism is contagious. If one vampire feeds on only two victims, which then become blood-suckers as a consequence, and they each feed on two ... Well, you can do the maths. It wouldn't be long before the wealthier Undead were paying for a private army of Van Helsings to keep the situation under control. Really, if you're going to spend your entire life drinking blood — the complete meal in a capillary — then it's a good idea to be smaller than your host or consume modest portions.

Ticks are small. Especially larval ticks. They don't each much at a sitting, either, even though a meal may last several days. And they make the most of their repast, retaining only the nutrient-rich component and regurgitating the bits they don't like. It's the tick equivalent of pushing the sprouts to the side of the plate.

Such a concentrated dinner keeps a tick going for a long while. Most feed only three times: once as a newly hatched larva, a second time as a nymph and a final time as an adult. A blood meal is a tick's rite of passage.

After gorging herself, an adult female tick finds a quiet spot for a nap and starts to digest her last meal. During the following days, she lays between 1,000 and 12,000 eggs. (Some species may produce even more.) Because she will not tend the clutch, she coats the eggs in a waxy material that prevents desiccation. The eggs don't pop out pre-coated — mum picks up each one as she lays it and transfers it to the clasper-like Géne's organs on her back, which secrete the protective wax. Fair enough then, that she loads up on the calories in preparation. That's a big job on an empty stomach.

On hatching, the larvae cluster together, waiting for some hapless vertebrate to blunder into their nest. And as that hapless vertebrate, I can verify they are so small that they can attach to the host without drawing attention to themselves.

Even at this young stage, they exhibit bad table manners. When … er … returning unwanted and waste material during feeding, they also inject a mixture of substances that temporarily stymie the host's immune reaction. Tick bites are painless at first and only start to become swollen, red and damnably itchy a day or two after feeding commences. Often ticks can complete their meal over the course of a few days and drop off before the host notices. And with close to two dozen bites from one brood — count 'em — I speak from experience.

On completing this first meal — the breakfast of their lives — the six-legged larvae turn into eight-legged nymphs. From now on they no longer hang around together but enter a Byronesque phase where they favour shady places, waiting for inspiration. Or, indeed, expiration because they can detect CO2 exhaled from potential hosts. (Another reason to minimise greenhouse gas emissions. Won't someone think of the ticks?)

Despite becoming a buffet for a generation of blood-feeding arachnids, I've developed both a grudge and a grudging admiration for them. I have also developed a mild sensitivity to their bites, so I'm glad that young tick season is almost over. In a few months it will be adult tick season. And then the leeches take over.

If only nailing garlic to the door worked with all blood-suckers.

Lake Eacham

I'm planning to get a bit more exercise by doing the circuit of Lake Eacham on a regular basis. (Note that 'regular' ≠ 'frequent' and could mean anything from every day to once a year.) It's only 3 km, so makes a nice post-breakfast walk. And rainforest is a good place to think.



Eacham is a crater lake at the eastern edge of the Atherton volcanic province. Like its larger sibling, Lake Barrine, and the cousin that we don't talk about (the crater at Mt Hypipamee) it is rumoured to be bottomless. I'm not sure how bottomless lakes work. Is there a constant inflow to counteract the evaporation near the Earth's core? Or is there is an equivalent body of water at the lake's antipodes, so you can dive all the way to the surface of whatever's on the other side? Which, if my calculations are correct — and they almost certainly aren't — is somewhere between the Mid-Atlantic Ridge and West Africa. So maybe the core acts as a still, super-heating the Atlantic Ocean, which then condenses as Lake Eacham. See, I said it was good for thinking.

(The crater is really about 65 m from rim to bottom.)

Turtle wonders whether it fancies a holiday in the Cape Verde Islands.

Not impressed

A pied currawong up to no good in an Atherton garden didn't appreciate getting caught in the act.

(Photo taken through window.)

New Hobby 2: Finding Sarus Cranes

Brolgas near Kaban, FNQ

The sarus crane (Grus antigone) is the other species of crane that occurs in Australia. Sarus cranes make regular appearances on the Tablelands, often in mixed flocks with brolgas (G. rubicunda). Following a tip, I headed off this afternoon to see whether any were hanging around with brolgas in the maize fields near Kaban.

Plenty of brolgas but no sarus cranes. Still, it's early days yet.

New Hobby 1: Diving Hardheads

Having cracked the secret of photographing grebes, I thought I'd move onto a different target. Hardheads (Aythya australis) are diving ducks and, like grebes, they usually dive just as you click the shutter. Hardheads are rather average looking ducks (I can say that because I'm pretty sure no hardheads are reading this blog), so they don't make the most engaging subjects for portrait shots. So I thought I would try to get a photograph of a hardhead in action: in mid-dive.

I haven't quite got the hang of it yet. They're quick and the shutter delay doesn't help. I've ruled out using the motor drive, because that's (sort of) cheating. It's my powers of prediction and reflexes against the wiles of a duck. So far the ducks are winning. But I'll get there.

Here are the results of my first attempt. I won't say how many photos included nothing but ripples.

Quantum Grebes

Australasian grebes (Tachybaptus novaehollandiae) exist in two states: diving and preparing to dive. It is impossible to predict what state a grebe will be in at any given time because it can switch between them instantly. And should you be able to get the camera focused on the bird in its preparing to dive state, by the time the camera shutter clicks the grebe will be underwater. On those rare occasions that you manage to photograph the bird on the surface, it will be out of focus. This phenomenon is explained by Heisenberg's Uncertainty Principle of Podicipedidae. With any given grebe, you can focus on it or you can get it in shot, but you can do only one of these things with precision.


This is a standard shot of an Australasian grebe — ripples and, occasionally, a fluffy white bum.

But sometimes, you can violate Heisenberg's Principle and get reasonable photographs. By uploading these I may cause a crisis in the world of theoretical physics, but I am prepared for the controversy. Here are pics of a trio of grebes that were sharing the shallows with the plumed whistling ducks at Hastie's Swamp, near Atherton.

Plumed Whistling Ducks

... are in fine feather at this time of year. Hundreds of them were resting in the shallows at Hastie's Swamp (near Atherton) this morning. Their white plumes looked almost ceremonial.

Road Trip, Some Time

On the Tablelands and heartily sick of motels. The main reason I moved out of Marvellous Melbourne was to get away from Other People. For the past couple of weeks, I've been stuck in even closer proximity to Other People and I have just about had enough. Well, I've had more than enough. Time for a spot of solitude.




Can't wait to settle into my new place, which (hopefully) will be sometime next week. Things are a little less organised than they could be. (Through no fault of mine or the Far North Queensland contingent.) In the meantime, here's a couple of photos of the garden of the Tropical Snail Shell.

Bowen's beaches: Mud

Before resuming my journey north, I made a short detour to Front Beach and King's Beach. (I was going to say that I also visited the Flagstaff Hill cafe for coffee and mango cheesecake, but that sounds so utterly implausible I thought you'd never believe it.)

Pied oystercatchers searched for food just above the water line, while a pair of sacred kingfishers (Todiramphus sanctus) hunted for stragglers stranded in pools by the receding tide.

Sacred kingfishers at Bowen's Front Beach

Road Trip, Day 10: Eungella to Bowen

Having left Eungella just after 7 am, so I could dawdle along the road*, I arrived in Bowen late morning. I'd initially decided that I'd detour to Cape Hillsborough and Dingo Beach but ended up driving through to my destination. I killed some time at the Flagstaff Hill café, which has mango and macadamia cheesecake and stunning views of the islands of Port Denison.

Today's new birds: yellow honeyeater and pied oystercatcher.

Foreground: North Head Island (with light) and Stone Island.
Background left: Middle Island with Gloucester Island behind.
Background right: mainland Cape Gloucester.

Bowen and Port Denison

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* I tried driving down in 3rd gear but my car insisted that I should do it in 2nd. I changed up, it changed down. Had it a voice, no doubt it would have gently admonished me: "I can't let you do that, Snail".

Rainforest palms 1: Livistona

The upland rainforests of Eungella include extensive stands of two species of palm: the cabbage palm Livistona cf australis and the bangalow or picabeen palm Archontophoenix cunninghamiana.

There's some discussion about the identity of the cabbage palm. It is generally regarded as belonging to L. australis, a widespread east coast species, but may be endemic to the Clarke Range.

This species is especially abundant on the tracks around Broken River. Semi-slugs and other invertebrates — including bitey ones — hide in the rolled up bases of shed fronds.

Sky Window

Sugar cane fields in Pioneer Valley, W of Mackay
(Click for larger image)

Eungella's Big Three

The name means 'mountain in the cloud', but it's not always cool and wet at Eungella. This time it was cool cold and dry. Excellent weather for keeping mosquitoes and leeches at bay but not so good for photographing snails.

Whereas Africa has its Big Five — the large mammals that tourists want to see — Eungella has its Big Three. Oh, yes, people may claim they're visiting Broken River to watch platypus but I think we all know what they're really here for — the snails Sphaerospira informis (Camaenidae), Pandofella whitei (Caryodidae) and Fastosarion superba (Helicarionidae).

I could only tick off one from my list this time: Fastosarion. These big semi-slugs like to spend the day in the rolled bases of palm fronds, where they are protected from desiccation. That's where I found these two.

Helicarionids are characterised by a thin, often transparent shell and a tail that looks as though it is folded vertically. Most species are semi-slugs in which the shell covers the organs of the visceral mass but is too small to accommodate the head and foot. Helicarionid semi-slugs are common in closed forests of the east coast but few are as spectacular as F. superba. (It's a relative measure.)

These two were rather sluggish. (Sorry.) Denis at Nature of Robertson has photos of a southern NSW helicarionid out and about. Imagine a semi-slug about three times as long and you've got the idea!

Road Trip, Days 7 – 9: Biloela to Eungella

I'd forgotten what it's like to drive up the range to Eungella, especially late in the day with the sun glaring on a filthy windscreen. Fortunately the sheer drops were on the other side of the road.

I went for a few walks in the rainforest and spent the rest of the time sitting around, reading and periodically looking through binoculars. It's a good combination. After three days at Eungella, though, I was more than ready to resume my journey.

The sun was in my eyes again when I drove down the range. But this time I'd cleaned the driver's side of the windscreen inside and out, making a nice little porthole. Once it stopped fogging up, I could see the only bit of the road I needed to see — the centre white line. Really, there is such a thing as too much information.

Birds: eastern yellow robin (NE form with yellow rump), white-browed scrubwren, white-throated treecreeper, brush turkey, emerald dove (green-winged pigeon), wompoo pigeon, fan-tailed cuckoo and female regent bowerbird. (The male was nowhere to be seen.)

Out of range

At Eungella, where there's no mobile phone access. Posting this from the lounge at Broken River, which has dial up. Not back within fast upload range until Monday, so A Snail's Eye View will be quiet for the weekend.

I now recall why it's taken me so long to get back to this marvellous place. I hate driving up that [expletive deleted] mountain. There's a gin and tonic on the table beside me now. Purely medicinal, you understand. For my ticker.

Livistona panorama

Chain Lagoon, near Taroom

(Click for larger image)

Definitely in Queensland

Pawpaws: if you can grow them in Biloela, you can grow them in Melbourne.

Bananas in Banana Shire

Isla Gorge

After a brief stop at Chain Lagoon, I drove on to Isla Gorge, where I had breakfast and offered a stern word to the trio of pied currawongs that kept landing on my car. They may have been trying to warm themselves up, because it was beak-chillingly cold, but I suspect they were really aiming to dismantle the windscreen wipers. They had that look about them.





Isla Gorge is on the eastern end of the Central Queensland Sandstone Belt. Just off the Leichhardt Highway, it's the most accessible of the national parks in this region. And it is a great spot for a break. But, if you visit at this time of year, don't forget to bring gloves and a beanie.

Click for a larger image

Caravans: park here

My breakfast table