Tag Archives: Australia

Kimberley Day 3 – Talbot Bay and the Horizontal Falls

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If you’re not into the savage beauty of extraordinary rock formations, then there’s nothing here for you. Move on…

Oh, still here?  OK, then.

Thursday 15 August – Before anything else, some geological background to the Kimberley.

I’ll be honest, I didn’t know exactly what “The Kimberley” meant, except as the highly scenic destination for a lot of cruise ships. Courtesy of one of the onboard lectures, I have learnt a few basic geological nuggets.

  • Everyone knows that bits of the Earth’s surface have moved around; at one stage most of the land was in a single great mass which had since drifted apart.  What I learned is that Australia is not just one of these drifting land masses, but is actually composed of multiple cratons – micro-continents – which over the millennia have crashed into each other and got stuck together – “sutured” in geology-speak.
  • It’s a law of geology that rocks accrete vertically, oldest, therefore, at the bottom
  • When lumps of land collide, unsurprisingly the bits of land at the edges do not have an easy time of it, and compete for superiority. One edge “loses” and is either forced underneath the other, (a process called subduction) or over it (obduction).
  • The Kimberley is the verbal shorthand for the Kimberley Basin, a craton which collided with Australia and got stuck to it around two billion years ago.

So, you can see that the land round the edges of the Kimberly basin is going to be full of these subductions.

Still with me?  Oh, goody!

Today we had arrived at Talbot Bay, towards the left-hand edge of the Kimberley Basin. One would therefore expect the rock formations to be somewhat tortured by this subduction/obduction process.

One would be right.

Here is what the area looks like under the serene gaze of Google Maps.

Geologically, though, there’s a lot going on.

 

The land has been buckled and twisted in a very unusual way. Erosion has worked its way through the more easily weathered layers, thus exposing those underneath.

OK, so what? I hear you cry. Well, you get to see some rock layers that are normally buried under millions of years’ worth of other rock. More to the point, though, the landscape is visually arresting, particularly now I’ve set it up for you.

So, there now follows a large number of photos of rock formations.  You may care to leave at this point in the symposium, or, alternatively, to skip to the bottom where something slightly less dull happens.

We cruised around for a couple of hours, giving us a opportunity to take lots of photos.

I hope you can see the extraordinary angles the layers have been buckled to – some are almost vertical and others remarkably twisted and distorted.

This is my particular favourite – the colour of the rock just blazed from underneath the darkness.

The darkness in all of these images, in many cases just above the water line, is caused by cyanobacteria. These would normally be a blue green, but when exposed to the light they go into stasis and their colour changes to dark grey or black until they are covered by water as the tides go up and down.

Ah, yes. The tides.

The tides are the cause of a phenomenon that pulls in tourists from far and wide.  Some of them like us, would be in boats; others would take seaplane tours, from platforms rather unattractively parked in the middle of the bay.

What attracts them is the behaviour of the tidal currents through a couple of gaps in the rock, one of which

is sufficiently narrow to create whitewater rafting-style currents.

But not for us, sadly.

Once again, that old devil moon was spoiling our fun; we were here at neap tide, so the thrilling flood looked more like, well, a dribble, really. It may not have looked like much, but the guides attempted to make things more exciting for us by jockeying for position in the stream.

Had we been here at spring tide, this is how it might have looked.

Now you can see why it’s called the Horizontal Falls.

It is – at the moment – a popular tourist activity to race up through the channel.  Our Zodiacs did not, out of respect for the customs of the indigenous tribes, for whom this area, traditionally called Garaan-ngaddim, is a powerful, sacred place; their belief is that boats that pierce these gaps disturb Woongudd, the serpent who creates this wonder by gliding between the cliffs.

Others at the scene were less respectful.

This was a craft from the luxury cruising ship True North

which was in the area at the time.

The practice will fairly soon be banned. Out of respect for indigenous customs? Or because there was an accident a couple of years ago? Your call.

In any case, it was just as well that none of the passengers described in that accident fell into the water;

this was a very large crocodile which we spotted further up the bay.

As well as the croc, and a couple of crabs and mudskippers, which I totally failed to get decent pictures of, we saw a plant called the Kimberley Rose.

It’s a deciduous tree, also known as the Sticky Kurrajong, or Brachychiton viscidulus
to grown-up dendrologists.

The expedition wasn’t the dramatic thing it might have been at spring tide, but the area is beautiful and the rock formations very impressive.

The morrow holds in prospect a visit to Bigge Island.  On the other hand, I’ve developed quite a severe sore throat. I hope that doesn’t presage anything unpleasant…

Kimberley Day 2 – Montgomery Reef and Freshwater Cove

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Wednesday 14 August 2024 – Today saw a morning Zodiac cruise and an afternoon landing. The cruise was to see one of the many extraordinary phenomena that result from the geology of the Kimberley – tidal water movement at Montgomery Reef. The afternoon was spent walking at Freshwater Cove.

So, Montgomery Reef, then.

If you look at the track of our Zodiac cruise on Google Maps, it looks very dull indeed.

However, add the Satellite layer, and you begin to see what we were cruising through.

In detail,

you can see we were cruising up a creek. Because we were there as the tide was falling, it presented an amazing sight.

The range of tidal movement around Montgomery Reef is very high.  At Spring Tides, it can be a 12m (40ft) difference between sea levels at high and low tides.  We were there at Neap Tide, so the movement is much less – about 5.5m (17ft).  As the tide rises, the water rises above the reef; when it falls, the water has to go somewhere, and the shape of the reef means that it spills over in multiple channels. I stole an aerial photo which gives a clearer idea of what’s going on here.

It’s not just pouring out in the channels; it’s running over the surface of the reef everywhere.

Montgomery Reef is somewhat different to a regular coral reef. Whilst coral reefs are usually composed of limestone from coral skeletons, shell fragments and the remains of calcareous algae, Montgomery Reef is an ancient terrestrial tableland created from the same rocks as the surrounding Kimberley Basin. Covering the existing features of the rock is a more recent layer of marine sediment, including calcareous coral, shell and algae. Calcareous algae in the form of rhodoliths (the yellowish chunk in the picture)

are the predominant reef building organisms on Montgomery Reef. Rhodoliths are unattached, photosynthetic organisms made of coralline algae, which aggregate to form complex communities and in the case of Montgomery Reef, act as a long barrier across the reef. (Tom, our guide for the cruise, explained some of this detail, and I got the rest from this fact sheet).

The water in the channel appears to have a problem that would be labelled “pollution” were it seen in the UK – scummy froth on the surface.

However, it is entirely natural. Because the reef spends so much (i.e. half) of its time exposed to harsh sunlight, the corals that have colonised the reef have developed a natural protective substance which acts as a sunscreen, and this finds its way into the water with the fall of the tides.

The creek we cruised along is the feeding ground for green sea turtles, and we saw several heads pop up as we went along, as well as some swimming beside the Zodiac.  Annoyingly, they were always on the shallow side so we (seated as we were on the other side of the craft) rarely got to see anything.  Our optimism that we would surely see some turtle action on the way back was dashed as we returned up the other side, so we never got our turn at looking for turtles nearby. The best I got was this bit of video, which shows a turtle basking in the shallows.  Yes it does.

The afternoon saw our first landing, which was at Freshwater Cove.

An indigenous family lives there, and every group was welcomed with a speech from the niece of the family and her sister, who narrated a story from the Dreamtime and anointed everyone with a dab of ochre on their cheeks – the dark colour of the ochre was explained by the story we heard. The building top left in the photo is an artist’s hut, where punters can relax and (preferably) buy souvenirs, such as the hand-painted T-shirts, decorated in traditional style by family members.

It was a wet landing, and the nice folk at APT had ensured that there would be towels for people to dry their feet in order to change into shoes suitable for the rest of the afternoon.  A couple of walks were on offer: a short one along the beach; and a longer one (2km out and back, up a hill) to see some aboriginal rock art.  We had opted for the latter. Dain, the expedition leader had stressed in yesterday’s briefing that some of the going was over rocks and boulders, and that there would be reasonably large rocks to clamber up and down. (He had laid a test, which was that people had to be able to step up on to the stage in the Laperouse Theatre without any assistance as a prerequisite for anyone wanting to do the longer walk.)

There was a reasonably well-defined track for most of the walk

and people obediently trudged along it.

Inevitably, for a group like this, progress was at a gentle pace, but it gave us a chance to appreciate the remarkable rock formations we passed.

We had to squeeze through a narrow gap between two substantial boulders.

This is known as the “dessert gap”, as it’s a test as to whether someone has gone heavy on the puddings during the cruise. (Spoiler alert – there is a way round for the portly!)

At the top, our group rested for a few minutes

because another group was below us looking at the rock art.  When they surfaced, we clambered down past a scene that looked like something out of Picnic at Hanging Rock,

but which was actually the roof of a wide-mouthed cave, on which one could see the rock art.

“Where is it, then?”, you might well ask on seeing that photo. “Digitally removed”, is the answer; we had been briefed that respect for the native traditions dictated that while it was OK to take photos for our own records, these were not to be shared or published on social media: it is not for us to tell their stories. That’s why you can’t see any of the paintings in the photo above. Something you can see, however, is the colonies of native bees nesting in the blackened holes along the top of the back “wall” of the overhang, whose honey is harvested by the local people.

The father of the family, a chap called Neil, described the history behind the cave, which was known as the “cyclone cave” for the protection it afforded when the weather got uppity. When asked how old the paintings were, Neil said they go back 65,000 years.  I did some intensive research asked ChatGPT about this and discovered that, generally speaking, Kimberley rock art could stretch back as much as 17,000 years;  so the figure that Neil used could well be the folk memory which inspired some of the paintings, as there is broad understanding that Aboriginal peoples have been in Australia that long. Whatever, the paintings have great historic and cultural import for the indigenous people. They depicted various aspects of life – stingrays, turtles, fish, cyclones and even the cautionary tale of a little boy, who had disobeyed his mother’s instructions and gone out on a fishing expedition, only to be sadly killed in an accident. So the pictures give lessons as well as tell stories. The art is touched up by the family every so often to keep it fresh but new paintings are not added

Jane and I didn’t find the walk at all arduous; I should jolly well hope not – the temperature was “only” in the upper twenties – we’ve walked much further in far hotter conditions – and the going was by and large not at all challenging bar the final scramble. However, a couple of members of our group were unfortunately not up to completing the walk back to the shore without issue. To be frank, I’m not surprised; some of the people on this cruise are quite crocked in various ways – aged, frail or otherwise not in good shape. APT had, though, prepared for this eventuality, and a medical team was despatched from the beach – at a run, complete with stretcher – to support the two who were having problems, and they both eventually made it back to the boat OK.

After we returned to the ship, we didn’t have long to wait for the evening briefing; just long enough to pick up a drink at the bar, actually.  Dain explained what we would be seeing tomorrow, a combination of interesting geology and further unusual tidal action, this time in Talbot Bay.  APT had organised a casino evening in the lounge, which we really weren’t all that interested in, so after a bite of dinner al fresco we repaired to our cabin and tried (with not a great deal of success, it has to be said) to get an early night, as we had to be up betimes-ish for the Talbot Bay activity. Which will be revealed, of course, in the next thrilling installment, which I hope you would like to read in the fullness of time.

Kimberley Day 1 – Lacépède Islands

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Tuesday 13 August 2024 – Today was to be the first expedition from the ship, to cruise on Zodiacs around the Lacépède Islands. There were three activities in preparation for this, one of which was mandatory, and so all the passengers had to sign in to make sure that everyone had attended. The expedition leader, Dain, first introduced the rest of the expedition team, a very diverse set of people and relevant skills, but all with clear enthusiasm for the job of making sure we punters got the best out of the time spent off the boat.

The next bit was the mandatory bit, which was a lesson on how to get on and off the Zodiacs safely. This was familiar territory for us, since the procedures were pretty much exactly what we’d learned and observed when we were in Antarctica. That had been a well-organised setup and it was reassuring to note that APT, who were running this cruise, took it every bit as seriously.

The final part was information about the destination for today’s expedition – the Lacépède Islands. The name was conferred in 1801 by the French explorer Nicolas Baudin during his expedition around Australia, in honour of French naturalist Bernard Germain de Lacépède, who described several Australian fish species. He dubbed the three islands Napoleon, Grant and Victoria. Then (we were told) the Brits came along, and renamed them West, Middle and East. Whatever, the islands have been identified by Birdlife International as an Important Bird Area, and are now an A-class reserve managed by Western Australia’s Department of Environment and Conservation. Rats (introduced accidentally during the guano mining carried out on the Lacépèdes as well as numerous other islands off the western Australian coast during the 19th century) were eradicated in 1986, allowing the recolonisation of the islands by nesting seabirds, prime among which are Brown Boobies; the islands are home to 18,000 nesting pairs. They are also Western Australia’s most important breeding habitat for green sea turtles.

No confusion about what wildlife we might expect to see, then.

It wasn’t a long journey to get there, so the skipper took it nice and gently, even temporarily altering course in order to get a slightly closer look at some humpback whales which were cavorting not too far away.

We could even see the occasional breaching by humpbacks in the distance, and some tail-slapping, too. One of the naturalists also spotted a sea snake swimming by.

The Lacépède Islands are noted for the variety of bird life there, and so we had a lecture from one of the guides to help us identify the birds that we might be able to catch sight of on our Zodiac cruise. Then, after a swift bite of lunch, it was time to man the Zodiacs. Since there weren’t enough to accommodate all the punters at once, we had been split into four groups, denoted by different colours, in order to get everyone out on the water in an orderly fashion.

Jane and I are in yellow group, who went first; and Jane and I happened to be in the first Zodiac out.

It was not difficult to see the Brown Boobies. They are curious birds, and it wasn’t long before they spotted us and a delegation came out to welcome us and check us out.

They are adept fliers (their name comes from the Spanish “bobo”, meaning a clown or a clumsy person, because they’re not elegant at all on land) and so presented a few challenges to capture photos of them as they whizzed around us.  But the trusty Nikon was up to the job, I’m glad to say, despite the difficulties I faced of accurately aiming a heavy lens at a distant moving object whilst seated on a boat which is rocking unpredictably.

They are slightly odd-looking birds at the best of times; then they stare at you directly, at which point

you see their very scary dementor faces.

There were quite a few crowded colonies of the birds visible as we cruised past, but they tended to be on rocks, which meant it was difficult to pick them out against the background,

but occasionally we could get a decent angle to show them as they rested and nested.

Our ship, Le Laperouse, in the background

We even caught sight of a couple of chicks.

No problem to see Brown Boobies, then.  It was also quite easy to spot this salt-water crocodile,

which was something in the order of three metres long. Xander, our guide and Zodiac driver, was assiduous in making sure we were seated as we passed by; crocodiles can move very quickly indeed, and this one might have made for the Zodiac with the intention of causing trouble.  If Xander had then suddenly and swiftly accelerated swiftly away in response, anyone standing might have then fallen overboard, which would likely cause a lot of paperwork. So we remained seated until we were sure it was just chilling [thermo-regulating, actually – Ed].

The other key wildlife member was much more challenging even to see clearly, far less to photograph. There were many green sea turtles around, but they were not at all obliging when it came to be ready for their close-up.  The best one could expect was, if lucky, to catch a shot of a head popping out of the water as a turtle took a breath, but one had to be very lucky to catch it.

I was not one of the lucky ones.

The best I could do was to get an image of something vaguely turtle shaped under the surface.  I hope this video gives some idea of how a typical encounter with a turtle ran.

Our time was up and so we headed back to the ship so that someone else could have a go on our Zodiac and, via some nice chocolate accompaniment to afternoon tea, had a bit of a rest before the evening briefing.  Similar, again, to our Antarctic experience, Dain, the expedition leader, ran a session which added a bit of background to today’s expedition (Xander telling us more about the life cycle of the green sea turtle), followed by a briefing of what was due for the morrow. Various options were on offer, some involving scrambling over rocks and some not. We opted for the scrambling over rocks version, which I hope was not an error of judgement on our part.

After the briefing came the a drinks reception, at which the captain introduced the senior crew members,

followed by a Gala Dinner, which was probably, judging from the quality of the meals we’ve had so far on the cruise, a sumptuous feast.  However, neither Jane nor I had the stomach for stuffing ourselves, and so we opted to stay downstairs and have a light buffet supper. Our original plan, which was just to eat à deux, unravelled when sociability and good manners led us to invite another couple, who had also decided against the more formal option, to join us.  So Jane had an enjoyable conversation with the engaging husband, which I would have been delighted to be a part of were it not for his wife’s annoying inability to refrain from injecting her own distracting, and not very interesting, converse in my direction. Unfortunately, it wasn’t possible to engineer a decently swift escape without being ruder than even I might consider acceptable.

One of the guides hosted a star-gazing session on the roof of the boat, which sounded interesting, so we went along. Unfortunately, the moon, although only half full, was bright and clear, which buggers up the chance of seeing all the lovely stars, and so I lost interest quite swiftly. I did, however, learn that the Perseids, through which the Earth is currently ploughing, should give rise to shooting stars here in the southern hemisphere, so I might try my luck later on in the cruise to watch out for them on another evening.

Tomorrow is set to offer two excursions, one on Zodiacs to view a particular phenomenon at Montgomery Reef, and the other one on land, to stumble along the rocky path we have signed up for and see what may be seen.  Keep your eye on these pages to see exactly what is was that we ended up seeing.