#004 Brickyard Full of Dreams

There is a place in the north where few swimmers go, and which is inaccessible in all but the lowest tides. Its name is Brickyard Park and it is perhaps the most splendid place in all of Gong.

 

Beneath the cliff the rock ledge stretches out a hundred metres into bright, deep blue ocean. Baitweed grows on every surface, making an emerald carpet of the ledge. A smattering of rock pools reflect a sky the colour of a robin’s egg. Rather than a shelf over the ocean, the Brickyard reminds one of a meadow in the sunshine after a storm.

When the tide is at its lowest waves slop against the eroding rock at the ledge’s chin. Water rush up white and foamy up a natural gutter, and when it drains back into the ocean, tall hanks of kelp are seen pulling tight against their moorings.

The pools are deep. Young Black Drummers and Common Silversides grow fat in the autumn, waiting for winter when they will migrate to the ocean. Families of leopard-print Smooth Toadfish chase each others’ tails, while Cocos Frillgobies, Jumping Blennies and Eastern Fortescues grow impatient, waiting for the months when the pools will be peaceful once more. Anemones, Eight-Armed Seastars and Elephant Snails cluster on the shallow verges of the pools, while urchins, oysters and Warreners live ever-changing lives on the substrate.

Here and there Sooty Oyster Catchers stroll, tall black birds with blood red legs and beaks, hunting for oysters, limpets and snails. Teenagers tremble in unseasonal bikinis, daring each other to leap into the ocean. With a whoop and a splash one is gone, paddling out into the depthless blue.

To the south is one can see the city, the rolling coastline and the great green bulk of the Escarpment. Late afternoon light spirals like diamonds from the crests of waves. This place is paradise.

coledale_2

Its moods change in an instant. In the rainy autumn season, the swell reaches eight feet. A fast-rising tide rushes up the gutter and fills the innumerable channels with white foam. With even an inch of water over the shelf, the Brickyard becomes dangerous, sudden deep pits and pools hidden beneath kelp to trip the unwary explorer. The shelf is swiftly cut off from the beach. A rockslip on the shelf’s corner forces wanderers out into deeper water, where an unpredictable current can rip away one’s feet.

There is no comfort even in the cliff at one’s back. Its verges are soft, prone to collapse. Rugged shrubs grasp the edge. Dozens of their number lay drying on the ledge below. Boulders the size of cars strew haphazardly at the cliff’s foot. This is not the place to be in a storm.

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Elephant Snails, Eight-Armed Seastars, urchins and limpets sunbathe in a shallow corner.

And yet the Brickyard is teeming with life. Existence here revolves around the Baitweed. Its satin emerald appearance makes Baitweed a visual pleasure, and it is soft and cushiony underfoot. It looks almost like grass spun from velvet. Baitweed can be eaten by humans, is full of nutrients and tastes good. However, humans are not the most important consumers of Baitweed. Fish, particularly Black Drummers and Ludericks, are so fond of Baitweed that they will even take it off a hook.

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#002 Baitweed (Ulva compressa)

Despite their infamy as some of Australia’s only herbivorous angling fish, in their infancy, Black Drummers are mainly carnivorous. They will eat small snails, Brine Shrimp and any stray bit of meat that happens their way. As they grow older, these fish incorporate more and more algae into their diets, until they become more herbivorous than carnivorous. It’s interesting to note that ichthyologists suggest there be no such thing as a purely herbivorous fish. When we consider land animals, we think very much in terms of “Cows are herbivores, cats are carnivores.” In truth, most animals are omnivorous, only to a greater or lesser extent. Cows and deer will supplement their diets with insects and the odd bit of meat, and “carnivores” such as dogs will happily include as much as 30% plant matter into their diets (not Salty. The closest Salty comes to a vegetable is maple-flavoured bacon.)

So while a Black Drummer starts life picking out the tiny snails and arthropods living amongst the strands of Baitweed, in later life they prefer the green algae itself.

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#115 Black Drummer (Girella elevata)

In the Brickyard, Black Drummers occupy large, deep pools, swimming in bands of three and four, generally governed by a “boss” Drummer. They are deep-bodied, strong fish. Infants are striped silver and dark grey, making them appear very much like silver striped Ludericks. As they grow older, the stripes fade, leaving Black Drummers somewhere between sandy brown, deep blue and black. They can also change colour with mood. In the Dangerpus Labs I keep three Black Drummers, Holly, Molly and Dolly. Holly is the boss and Molly is a boy. I often watch them after being fed, where Holly becomes a stormy dark grey and flashes around the tank with her dorsal spines erect and her gill coverings open. She makes her appear as big and intimidating as possible. Her sister, the docile Dolly, will become a buttery silver, keeping to herself near the bottom of the tank.

Once, when I introduced a new fish into the tank, Holly turned such a jet black that her dark grey stripes (she was quite young at the time) stood out in stark relief. She then swam slowly backwards around the new fish. It was clear to everybody that Holly was not happy.

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Keen tracks Black Drummers. Note the field of Baitweed colouring the rocks green. This entire shelf is usually submerged.

There is one more animal to keep your eye out for in Brickyard Park: the Elephant Snail (Scutus antipodes). While uncommon elsewhere, in the Brickyard Elephant Snails are in abundance.

These huge black gastropods are the largest of the false limpets, growing up to 150 mm in length. They are generally sedentary creatures, though can move quickly when disturbed. You will know one when you see one! In the Brickyard they hang around the verges of pools, in crevices otherwise populated with seastars, urchins and limpets. They are massive black blobs with two distinct antennae and a white shield-shaped shell. If you put your finger gently to the snail’s back, you can pull the black membrane right up over the shell. If you do this, there will undoubtedly be some baffled antennae-swaying on part of the snail, but they are soft and muscular and quite pleasant to stroke. If I had the strength to break their suction-grip on the rocks, I would very much like to let one crawl around my arm.

 

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#028 Elephant Snail (Scutus antipodes) … Good old Scutus. A good bloke, that Scutus.

Elephant Snails are algae feeders, but do they eat Baitweed? I don’t know. That is something I need your help to find out. Also interesting is that Baitweed is known to grow in polluted sites with high levels of nutrients, such as fertiliser runoff. This kind of pollution is always a risk near coastal towns, but the Brickyard is especially notable for its abundance of Baitweed. Is there an especial amount of runoff reaching the water from Coledale township?

Join Salty and I next time for a close encounter of the eight-legged kind as we get close and personal with a Gloomy Octopus, and I go swimming with a Wobbygong shark.

Until then, happy exploring!

 

 

Secrets of the Rock Pools

The quest to uncover the secrets of rock pools continues…

Have you ever wondered exactly what is living in the pretty little rock pools scattering the beach? You hear the crunch of littoral snails underfoot and gaze out upon a veritable starfield of similar creatures: little blue and grey shells in hunkering packs on every available rock, others clustered like refugees at the edges of pools. Now and then you may see the silvery flash of a fish darting for cover. A crab may scuttle under a rock, or bump into another crab and simply stand there, wondering what to do. As you peer deeper, you begin to make out the long red spines of urchins, the mottled blue and green backs of sea stars, and a lonely sea hare drifting amongst pink fronds of coralline algae.

But life in the rock pools is tough. Temperatures are extreme, salinity ranges wildly from hypo to hyper in the space of a rain shower, the waves constantly hammer, hammer, hammer, throwing in new cell mates and dragging out the old, pushing in sand and cold water, offering respite and obscuring shelters in the same breath. Birds circle, and humans flounder clumsily over generations of nerites, and big crabs drive the small crabs to the lesser hunting grounds, and small crabs strip away generations of nerites that the humans couldn’t get to.

Just what are the limitations of life in this war zone? What stops a blenny from living in two inches of water? Is it the hypersalinity? The temperature? Predation from birds? Or is it simply a lack of space? Similarly, why will a green anemone attempt to take root in half a centimetre of water in the midst of a minefield of Pacific oysters?

I wanted to know. And, because no one tried to stop me, I picked 11 rock pools out on a bluff at my local beach to study with the intensity of Charles Darwin observing a barnacle. If you haven’t caught it, you can read my first post of Crab Bluff here, or what the hell, jump right in, the water is warm (-er than ambient temperature.)

High tide at Thirroul Beach averages 1.525 metres above the datum. Low tide averages 0.46 metres above the same datum. Average water level is 0.99 m, meaning anything less altitudinous than 0.99 m is inundated more often than not, and anything above 0.99 m is exposed more often than it is inundated. All pools surveyed on the Bluff remain above the waterline even during high tide.

The Pools

#1 Little Crater

1

Volume: 0.24 L

Temperature: Warmer than ambient.

Exposure: This pool could be considered submerged at high tide; water constantly pushes over Big Pool into a water course encompassing Little Crater and Dry Triangle. This stream then flows across the back of the Bluff onto the beach.

As the water drops, less and less water flows over this pool, until the stream narrows and dries to isolate Little Crater. After isolation, water in this pool quickly evaporates, reducing its small volume even further.

Species:

This tiny pool is devoid of sheltering algae. What life there is clusters around the overhanging crater lip.

Molluscs:

  • Little blue periwinkles (Austrolittorina unifasciata)
  • Pyramid periwinkles (Nodilittorina pyramidalis)
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What little there is of Little Crater, with scattered little blue periwinkles.

#2 Dry Triangle

2

Volume: 211 L

Temperature: Cooler than ambient up to the point of isolation. Shallow depth means it warms rapidly.

Exposure: As with Little Crater, this pool could be considered submerged at high tide. Water constantly pushes over Big Pool into a water course encompassing Dry Triangle. The pool is shallow with low walls and so the water in it is constantly changing. Outlets are to #3 Left Twin and in the tidal stream running down the back of the Bluff.

As the tide recedes, this pool still receives water, but is changed far less often. Volume is still above that of isolation. Ninety minutes from low tide, the pool is isolated from incoming water. It continues to output a small amount to #3. Eventually the pool is drained completely, and remains dry until it is restored by the rising tide.

Species:

Prone to being drained, there is no macroalgae in this pool.

Molluscs:

  • Pacific oyster (Crassostrea gigas)
  • Striped conniwink (Bembicium nanum)
  • Little blue periwinkle (Austrolittorina unifasciata)
  • Pyramid periwinkle (Nodilittorina pyramidalis)

Crustaceans:

  • Swift-footed crab (Leptograpsus variegatus)

 

#3 Left Twin

3

Volume: 105 L

Temperature: Offers sustained respite from high ambient temperatures.

Exposure: At high tide this pool receives regular water from the tidal stream. #2 runs into this pool even after the tide has receded. Additional water is provided by large waves. Left Twin outputs into Right Twin, which then flows down the back of the Bluff. As the tide reaches average height, inlets and outlets to this pool stabilise, leaving it isolated.

Species:

On original observation, this pool was deep with a rocky substrate, harbouring numerous small algae. In early December a storm pushed sand into the pool, halving its volume and obscuring most of the algae. Young crabs still find it a convenient hiding spot on their hunting ventures.

Molluscs:

  • Black nerite (Nerita atramentosa or N. melanotragus … orange and black operculum suggests melanotragus)
  • Pacific oyster (Crassostrea gigas)
  • Pyramid periwinkle (Nodilittorina pyramidalis)
  • Striped conniwink (Bembicium nanum)
  • Little blue periwinkle (Austrolittorina unifasciata)

Crustaceans:

  • Swift-footed crab (Leptograpsus variegatus)

Annelids:

  • Spirorbid worms (Spirorbis sp.)
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Orange and black operculum on Nerite sp. Note cute spirorbid worm spirals on shell.

#4 Smoking Gun

4

Volume: 85 L

Temperature: Warms rapidly after isolation.

Exposure: Inundated at high tide from backwash across the Bluff, this pool is otherwise relatively higher than the rest and so protected from most inlets. Still, rough wave action sees a total water change of this pool at least once per minute.

Two hours after high tide, no regular inlets remain, and there is only one small outlet to Dry Triangle.

Species:

While shallow and readily overlooked, this pool contains a good deal of encrusting and stringy algae, and supports a surprising amount of life.

Molluscs:

  • Black nerite (Nerita sp.)
  • Little blue periwinkle (Austrolittorina unifasciata)
  • Pyramid periwinkle (Nodilittorina pyramidalis)
  • Striped conniwink (Bembicium nanum)
  • Zebra winkle (Austrocochlea porcata)
  • Variegated limpet (Cellana tramoserica)
  • Flamed limpet (Notoacmea flammea)
  • Pacific oyster (Crassostrea gigas)

Crustaceans:

  • Swift-footed crab (Leptograpsus variegatus)

Annelids:

  • Spirorbid worm (Spirorbis sp.)

 

#5 High Triangle

5

Volume: 99 L

Temperature: With no spray to refresh it, temps reach ambient and above.

Exposure: High Triangle is the most isolated pool tested. Its west banks are dry even at the peak of high tide; it’s a safe place to stand and not be doused. Water, even spray, does not reach is regularly. Silty sediment on the pool’s bottom and persistent crab skeletons suggest only in rough weather and rain does this pool receive new water.

Species:

Any algae in this pool is on the micro scale. A few hardy periwinkles are all that survive here. On hot days they clustered above the pool’s edges. The empty white carapaces of crabs drift along the silty bottom.

Molluscs:

  • Little blue periwinkle (Austrolittorina unifasciata)
  • Pyramid periwinkle (Nodilittorina pyramidalis)

 

#6 Big Pool

6

Volume: 8998 L

Temperature: Cooler than ocean – possibly due to high evaporation levels from Big Pool.

Exposure: Hammered and inundated by violent wave action at high tide, this huge pool has outlets into the ocean on its east side and a tidal stream on its west side. Rock forms a natural funnel at this point of the Bluff and white water jets dramatically over Big Pool.

Two hours after high tide, far less is received and output. The water level remains about 5 cm above the pool’s algae line. On Big Pool’s surface, the only hint of its violent past are in the foam and shredded bladderwrack.

Species:

Big Pool is home to all sorts of interesting creatures washed in from the sea. Large amounts of coralline algae, sand and rocky crevices provide a multitude of lifestyle options, and creatures here are both visitors and regulars.

Arthropods:

  • Honeycomb barnacle (Chamaesipho tasmanica)
  • Rosy barnacle (Tesseropora rosea)

Molluscs:

  • Warrener (Turbo undulatus)
  • Mulberry whelk (Morula marginalba)
  • Black nerite (Nerita sp.)
  • Tent shell (Astralium tentoformis)
  • Zebra winkle (Austrocochlea porcata)
  • Striped conniwink (Bembicium nanum)
  • Little blue periwinkle (Austrolittorina unifasciata)
  • Variegated limpet (Cellana tramoserica)
  • Sea hare (Aplysia sp.)

Anemones:

  • Green anemone (Aulactinia veratra)
  • Shellgrit anemone (Oulactis muscosa)
  • Pacific oyster (Crassostrea gigas)

Echinoderms:

  • Tuberculate urchin (Heliocidaris tuberculata)
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Big Pool at high tide. Ride those waves!

#7 Stream Pool

7

Volume: 9.6 L

Temperature: Struggles to remain cool after isolation.

Exposure: Although this pool is high above the water, waves channelled against the Bluff jet into it, changing its volume several times a minute. It outlets to Big Pool.

Two hours after high tide, Stream Pool receives far less water and is not inundated, though it still receives regular small doses from wave action.

Species:

This narrow crevice is thickly grown with Pacific oysters. A few very small urchins also hide out amongst the regular smattering of littoral snails.

Molluscs:

  • Pacific oyster (Crassostrea gigas)
  • Black nerite (Nerita sp.)
  • Zebra winkle (Austrocochlea porcata)
  • Striped conniwink (Bembicium nanum)
  • Little blue periwinkle (Austrolittorina unifasciata)
  • Variegated limpet (Cellana tramoserica)

Anemones:

  • Shellgrit anemone (Oulactis muscosa)
  • Green anemone (Aulactinia veratra)

 

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Shellgrit anemone, full of sand and grit.

#8 Elephant Pool

8

Volume: 162 L

Temperature: Pool temp measured in the afternoon was cooler than the ocean temp measured in the morning. Could be due to evaporation, or cooler waters pushing onto the beach after initial ocean temperature was measured.

Exposure: Elephant Pool is the most exposed of any pool tested. It receives intense wave action during high tide, with water constantly pouring in and out of this deep pot of a pool, often violently.

Even at low tide, this pool continues to receive water, and is always at capacity. Its only outlet is the ocean.

Species:

Generous algae grows provide shelter and food for the curious inhabitants of this pool, all of whom seem to be regulars. In particular, a pair of large elephant snails hide amongst the sea grass at the bottom, while crabs and urchins tuck themselves into a deep crevice.

Anemones:

  • Green anemone (Aulactinia veratra)

Arthropods:

  • Swift-footed crab (Leptograpsus variegatus)

Molluscs:

  • Elephant snail (Scutus antipodes)
  • Zebra winkle (Austrocochlea porcata)
  • Black nerite (Nerita sp.)
  • Striped conniwink (Bembicium nanum)
  • Little blue periwinkle (Austrolittorina unifasciata)
  • Variegated limpet (Cellana tramoserica)

Echinoderms:

  • Tuberculate urchin (Heliocidaris tuberculata)

 

#9 Big Crater

9

Volume: 229 L

Temperature: Is able to resist some heat from the sun after isolation. This measurement, taken at nearly low tide, suggests the pool would reach ambient temperature before regular cool spray was restored.

Exposure: Regularly sprayed in high tide, where it sits above capacity with only a small outlet draining to the ocean. This pool’s depth and sides give it some protection from wave action. Pool #10, High Half-Crater, also flows into Big Crater.

Two hours after high tide, this pool is close to its isolated volume. It receives only spray, and retains a small volume outlet to the ocean.

Species:

The deep bowl of this pool is a nursery for snail eggs. Young crabs hang out at this pool in the manner of kids at a skate park, having been pushed back from the Bluff by their old folks.

Arthropods:

  • Swift-footed crab (Leptograpsus variegatus)

Molluscs:

  • Little blue periwinkle (Austrolittorina unifasciata)
  • Black nerite (Nerita sp.)
  • Zebra winkle (Austrocochlea porcata)
  • Pacific oyster (Crassostrea gigas)
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A curious Zebra winkle.

#10 High Half-Crater

10

Volume: 68 L

Temperature: Approaching ambient after isolation.

Exposure: Despite this pool’s proximity to the ocean, it is readily isolated by its height and orientation in the rocks. It receives spray only in high tides and rough weather, and more regular inlets across the Bluff from the back of #11, Neptune’s Crater. Here large waves increase #10’s volume and change its water regularly.

Two hours after high tide, the pool’s outlets to #9 Big Crater have subsided, and it receives little new water.

Species:

A small Neptune’s necklace grows here; otherwise algae is microscopic and the pool is superficially barren.

Molluscs:

  • Little blue periwinkle (Austrolittorina unifasciata)
  • Zebra winkle (Austrocochlea porcata)
  • Black nerite (Nerita sp.)

 

#11 Neptune’s Crater

11

Volume: 4 L

Temperature: While small, this pool’s proximity to the ocean keeps it cool. The shade from the many Neptune’s necklaces might also help.

Exposure: This pool rests in a wet site near the ocean edge of the Bluff, where it is doused several times a minute even in receding tides. As tide recedes, waves tend to strike the Bluff wall and then shower down on this pool. Action is intense and disruptive but not violent.

Two hours after high tide, the outlets to #10 and the ocean have subsided, and the inlets from waves are less regular; perhaps not even once a minute for a decent douse of spray.

Species:

Neptune’s necklace grows thickly here, fronds obscuring the surface of the small pool and providing plenty of cover for its inhabitants.

Anemones:

  • Green anemone (Aulactinia veratra)

Molluscs:

  • Black nerite (Nerita sp.)
  • Zebra winkle (Austrocochlea porcata)
  • Striped conniwink (Bembicium nanum)
  • Pacific oyster (Crassostrea gigas)

Crustaceans:

  • Swift-footed crab (Leptograpsus variegatus)

Arthropods:

  • Isopod ~

Annelids:

  • Spirorbid worm (Spirorbis sp.)

 

Conclusions:

12

Regular inlets do a lot for a pool. Those pools receiving regular wave and spray action are closer in temperature to the ocean, while those more isolated at the back of the Bluff or higher up can be even hotter than the air temperature.

This means one, that the degree of isolation is a vital component of temperature. Two, that isolation determines what species may survive and flourish in a pool. Also interesting to note is juvenile crabs seemingly pushed back away from the edge of the Bluff, itself a wall of good hiding places, to hunt in the landward pools.

  • Are these young crabs displaced from fertile hunting grounds by larger crabs?
  • Why are larger periwinkles (Austrolittorina unifasciata and Nodilittorina pyramidalis) found in the hottest and most isolated pools – is this to prevent competition with their young?
  • What role is played by salinity and water quality in determining species variation and distribution in the pools?
  • The ocean provides a stable temperature: at night as well as day. How does pool temp behave at night? More day testing is also needed for better results.
  • A cooler daytime pool seems to provide better species diversity, as does accessibility to the ocean. Is this actually because of more stable temperatures, or due to the likelihood of creatures being pushed into the pool by waves?
  • What is the role of substrate – rock, sand, algae – in keeping a “local” population in a pool?

Join us next time for more rock pool action on Danger Ball Z!

The White Globster

It was a stormy day in early November when I happened upon the grey and battered beach. Brown lumps of bladderwrack heaped on the sand like walruses on the high tide line. Huge cups of banded fanweed nestled in the wrack. Death was in the air as dozens of sea squirts pushed one last feeble breath of water from their aorta-shaped siphons.

Then there was the Globster.

Startling white it was, with a mass of tentacles like so much upturned udon. It splayed limp yet plump on the wet sand, commanding the beach not by its size but by its sheer unknowability.

I approached with suspicion in every sodden step. Was this some monstrous anemone risen from the deep? Some nest of hideous marine worms? Or was it something altogether more sinister and strange?

Cold drizzle peppered the back of my neck as I bent over the weird lump. I found a stick and turned it over. The mass was firm and jellylike, damp, with an inner sheen. It neither quivered nor tried to escape my cautious prodding. Recalling that everything in the sea is venomous, I drew a tentacle away from the mass with the end of the stick. Each individual tentacle appeared to taper down to a fine string, woven into a net encompassing a mass of detritus. The mass had no apparent foot or mechanism of defence. I knew it had to be toxic.

The seagulls kept their distance as I wandered the short bay, overturning bladderwrack with my stick. More white masses were exposed. Two more were large, the size of an adult’s brain. Another two were not much bigger than my balled fist.

The rain drove harder. Sheets of water fell across the sea. To the west, the escarpment was cloaked in deep grey cloud. A momentary merging of sea and land. Alas, I do not have gills. In lament of a bag and gloves, I left the Globster for drier land.

 

PENTAX DIGITAL CAMERA
Artist’s rendition of author’s description.

Only to return the next day. The small masses were gone. So was the week of heavy rain and cold water pushed from beyond the continental shelf. Sun shone on the bladderwrack, baking it crusty and black. The two large white masses had survived well, one slightly dehydrated. In its greying mass were revealed paler lumps. Each tendril carried five lumps, giving them the appearance of too-many jointed fingers.

I tried to guess how many tendrils there were. A hundred, two hundred? Could it be an egg mass? Thinking of anemones, I checked the creature for a mouth. A pair of silver gulls watched from a distance. There was no mouth.

Eager now, knowing the creatures were dead (if they had ever been alive) I found the stick I’d wedged in the sand and gently peeled tendrils away from the central mass. A grey stretchy latex-like material bound the tendrils to a central net, the gatherer of debris. Twigs and stringy weeds littered the tendrils. It was impossible to tell whether the tendrils were poking through the grey latex or were part of it. I would have to dissect it to find out.

Curious now more than I was frightened, I lifted one large mass on a stick and carried it to the water’s edge. When it dropped into the foot of a wave, its tendrils bloomed out weightlessly and carried the mass back to shore. It was limp, unresponsive, even in the water. But for the first time, it was not some hideous monstrosity washed up on the sand. In the water, one could see that it was functional, even beautiful. Its shape was that of a dozen jellyfish arranged on a multi-tiered cake stand. Alien as it was, it was somehow elegant.

I picked up the mass on the stick and flung it into deeper water. Whatever it was, if it had any chance of survival, it was in the sea.

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The Globster.

Work beckoned in the afternoon, but all I had were questions about the solitary white mass left on the beach. I couldn’t tell if the thing were plant or animals. If it were dead or alive. I was unsure if it were a collective or single organisms or a strange clutch of eggs.

The home bell struck. I wandered into the workshop and picked a rubber glove from the box the mechanic keeps on his toolbox.

“I’m taking this,” I warned him. “And you won’t want it back.”

The mechanic was still shaking his head over the news that Trump looked to win presidency and didn’t deign to answer.

Well, forgiveness is easier attainted than permission, so I took my plastic bag and rubber gloves and trotted down to the beach. Right in the middle of Thirroul Beach are the big yellow buildings of the local surf lifesaving club. I ducked under the boathouse door and knocked on the tin roller. A couple of lifeguards on duty in the booth looked around.

“Come in, come in!” said the older of the pair, ushering me up the stairs to the booth. Beneath the panorama of rolling waves were clusters of tide charts and shift rosters. “What can we do for you?”
I shrugged. Regardless of the answer, I knew what I was going to do. “There’s a weird white thing washed up on the beach. I was wondering if you might know what it was?”

A brief description of the creature – like an overturned bowl of noodles – didn’t spark any fires, so I brought up a picture on my phone.

“Ew,” said the younger lifeguard. “What is that?

“Never seen anything like it here before,” said the older. “What is it?”

“No idea,” I said. “But if you don’t mind, I might collect it and take it to the University for IDing. That’s if you don’t mind.”

Both lifeguards made noises of encouragement.

“Go do it!” said the older one as I ducked back under the roller door. “Make sure you come back and tell us what it is.”

Thusly bidden, I trekked up the beach, barely able to keep from running in the fear that the white Globster had already been taken, by man, tide or seagull, but equally gone.

But there it was, caught in the seaweed pushed up during the afternoon’s high tide, but not washed away. I donned gloves and bagged the mass. I scanned the beach. Not another mass was to be seen.

Though it was the more dehydrated of the two large masses, the thing was heavy. Heavy enough that I wandered into town and into the supermarket, where I sat the inconspicuous bag on the vegetable scales. 450 grams – a full pound.

Heavier still was the news that Trump had won the presidency. There was gloom in the workshop as I went to fetch the car. “This will cheer you up,” I said, to the pair of mechanics languishing by the radio. I opened the bag. “Guess what this is.”

The head mechanic peered into the bag. The scent of clean seawater drifted back. “Um. Is that a squid?”

“It’s an anemone, obviously,” said the hired help, an erstwhile technician resembling a seagull. “Clear as day. Anemone.”

“Anemones have mouths,” I told him. “This thing doesn’t. They also have tapered tendrils; these are blunt. It’s not an anemone.”

“Then it’s worms,” he said, but like the rest of the seagulls, he kept his distance.

Back home in the lab* I filled a bucket with water and spread out the dissection kit. Armed with tweezers and a scalpel, I began the long work of extracting debris from the tendrils. Soon I could see that a grey rubbery net bound the mass together, forming a cylindrical body distinct from the fronds of tendrils. Floating the mass in the bucket, these fronds became apparent; tiers of tendrils arranged around the narrow body. Furthermore, the body extended into a dark grey, thick rubber knob. Roots extended from one end of the knob; a hank of seagrass from the other.

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*We used to have a sun room, but since I moved in we have a lab.

A housemate wandered into the lab. Trump’s election speech had just played twice on the television.

“What is that?” said my housemate, Mungus. “It looks like the state of American politics.”

Mungus is an avid dissector and taught me all I knew. I could use his help on this project. “I don’t know what it is. Wanna help me dissect it?”

“Ooh!”

“Take gloves though,” I said, indicating the pack of latex gloves I’d bought as a cover for using the supermarket’s vegetable scales. “It’s probably venomous.”

Mungus took a glove and a razor blade. He sliced of a tendril. While the tendrils had some size variation, they averaged about the size of my pinky finger. Each one contained five transparent lobes kind of like young beans in a pod. Mungus ran the razor blade over the membranous skin of the tendril, cutting it open and extracting a lobe. It dissolved into water in his fingers. It truly seemed like we had some alien on the cutting board.

I cut through another, careful to avoid the lobes. The tendril was the texture of a gummy worm on a hot day. A stretchy membrane hooked on the scalpel and refused to tear. I yanked it and the entire thing split open. Each lobe averaged 8 mm long and 4 mm wide. As carefully as I lifted a lobe on the edge of the scalpel, it dissolved into water.

“Let’s cut through this part,” said Mungus, indicating the dark grey knob. He held it and I cut, slicing through a 15 mm wall of warm rubber.

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Knob with seagrass growing through centre.

“This plant grows right through it,” I said, to break the stunned silence. It was as if the plant had grown right up through this thick rubber tube.

“Is that plant part of it?” said Mungus. “Is this thing part plant, part animal? See the beads on the roots – they look just like the lobes on the tendrils.”

There seemed to be no more to the Globster. No brain, no lungs, no recognisable organs at all. Just the white tendrils and this grey knob with its symbiotic plant. Mungus took a photo.

“I’ll send this to a biologist professor friend. He might be able to help.”

He sent the photo via Messanger and soon we had a reply. ‘No idea! is it an anemone?’

“It’s not an anemone,” I said to Mungus, before he could say it. “It’s nothing like an anemone. We need another biologist.”

It was with a bit of searching that I found an email address for a chap in the University’s marine biology department. But email is slow compared to IM, and it was unlikely I’d hear back that night. I wrapped the Globster in catalogues and stowed in the freezer.

“Maybe we’ve found something new,” I said to Mungus that night. “Maybe it’s something really different.”

“Maybe they’ll name it after us,” said Mungus. “The Mungusopus anemone.”

“Let’s hope not.”

Mungus made eyebrows, and kept his peace.

For the next 20 hours, I checked my phone at every opportunity. Mungus texted me on the hour, every hour. The professor’s reply (and the news of our Nobel Prize) was unforthcoming. The lifeguards asked if we’d had any luck; I had to tell them no.

When at last the email arrived, it was simple, one line.

‘Egg mass. Squid or octopus sp.’

I messaged Mungus immediately. ‘We found something AWESOME. Squid egg mass.’

He replied within the minute. ‘Holy crap. That’s incredible. That’s the coolest thing I’ve ever heard.’

A little research led to the tentative supposition that the eggs belonged to a Sepioteuthis australis, a Southern calamari squid. Common in shallow waters, the squid lays fronds of eggs that attach via a tough rubbery mass to plant matter on the seabed. Our grey knob was an anchor, tethering the mass to a hank of seagrass. The eggs were most likely freshly laid, being small and readily dissolved; as they develop, the eggs become more beadlike. The masses I’d found on the beach must have been yanked from their moorings like boats in a storm by the week of rough weather.

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Sepioteuthis australis, Southern calamari squid.

I went around to the surf club that evening to tell the lifeguards the news. “I’ve never seen anything like that on the beach,” said the older lifeguard. “You find anything else weird, come show us!”

Their enthusiasm was oddly charming. “Of course.”

That evening in the lab, I felt a slight sting of disappointed that we had not discovered anything new. The Mungusopus anemone was not to be. Yet so much more than disappointed, I realised I was thrilled. The ocean contains so many mysteries. The White Globster was only the first.

Crab Bluff

At low tide on a Thursday evening, Keen Wasabi and Salty (and every other dog on the beach) joined me for chicken sandwiches and rock pool-measuring at Thirroul Beach’s Crab Bluff.

I knew I wanted to do a population survey – I wanted to know every living species on Thirroul Beach. If only it were that simple.

As a landlubber all my life, it took me weeks of loitering at the Bluff to figure out just what I was looking for in a population survey. I could see that different species of sea snails preferred different areas of the beach – striped Zebra tops (Austrocochlea porcata) remaining submerged at low tide, while the nodular Pyramid periwinkles, (Nodilittorina pyramidalis) hung around at the dry edge of the spray zone.

However, what I was mainly aware of was that I knew nothing. I didn’t even know what I didn’t know, because I didn’t know anything. I wasn’t sure what was a limpet or a barnacle or a rock oyster or an urchin or an anemone. And the seaweed seemed important – but what kind of plant grows in saltwater? I knew so little in those early weeks that I inhaled information, spending hours browsing sites like the Australian Museum’s zoological resources, sea shells of Australia and endless Wiki pages on tides, littoral zones and marine snails.

At last I felt equipped with a basic knowledge set. I spent a few days at the south end of the beach past the pump house, out on Crab Bluff, which is above the tide in all but the heaviest storms. Rock pools on the Bluff each had different animals and algae, some webbed with Neptune’s necklace, others shallow and dotted with infant periwinkles and conniwinks. Still others held big red urchins, swift-footed crabs, elephant snails and gobies.

I had a vague idea that it may have been proximity from the ocean that determined what lived where. Out of the hundreds of pools on the Bluff, I settled on 11 that are close to each other, display a variety of depths, volumes and distances from the ocean, and that can be accessed even at high tide.

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Map of pools chosen on Crab Bluff.

Next I needed data. Lots of it. Data about the pools, the beach, and the animals that lived there. While some of the information, such as tide times and heights and ambient temperature, could be sourced online, the bulk of info I was going to have to collect myself. To do that required narrowing down and focussing on what I wanted to do, resulting in a series of actionable steps.

  1. Choose pools based on proximity to ocean and variety of life.
  2. Measure pool area and depth to calculate volume. Note substrates.
  3. Measure pool temperatures and compare to air and ocean. Note species.
  4. Conduct water testing for pH, ammonia, nitrate, phosphate and salinity. Count populations.
  5. Compile results and draw conclusions about what’s there and why it’s there, and how it interacts with other species.

Splitting the steps this way meant I could gather information across different days, giving me time to reflect on what I’d learnt and what needed improvement. It would also mean that I could modify my hypothesis: if proximity to the ocean turned out to be a dead end, I could add additional testing for salinity, temperature and other factors that I may not yet be aware of.

But there’s no time like the present. The pools were selected, a yard stick made from a length of bamboo, and the aid of Salty and Keen sequestered.

We met on the Bluff as the sun sank below the escarpment. Salty and I shared a chicken sandwich. The tide was low, leaving the pools isolated, and crabs hung thick on the wall above the water. Keen took up pen and paper as I wrestled Salty for the yard stick.

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Salty offers Keen instructions on proper yard stick use.

Results for pool measurement:

# 01 Tiny crater

Shape: Circle, 13 cm diameter
Surface area: 132.73 cm 2
Average depth: 1.8 cm
Max depth: 2.5 cm
Volume: 238.91 cm3 (0.24 L)
Distance from ocean: 5.0 m
Substrate: rock

# 02 Dry triangle

Shape: Triangle, 116 x 83 x 126 cm
Surface area: 4682.56 cm2
Average depth: 4.5 cm
Max depth: 9.5 cm
Volume: 21071.52cm3 (211 L)
Distance from ocean: 5.0 m
Substrate: sand on rock, small pebbles

#3 Left twin

Shape: Rectangle, 110 x 53 cm
Surface area: 5830 cm2
Average depth: 18 cm
Max depth: 31.5 cm
Volume: 104,940 cm3 (105 L)
Distance from ocean: 6.3 m
Substrate: sand

#4 Smoking gun

Shape: Triangle, 154 x 147 x 173 cm
Surface area: 10644.48 cm2
Average depth: 8 cm
Max depth: 15 cm
Volume: 85155.85 cm3 (85 L)
Distance from ocean: 5.5 m
Substrate: rock, black lichen

#5 High pool

Shape: Square, 180 x 110 cm
Surface area: 19800 cm2
Average depth: 5 cm
Max depth: 9 cm
Volume: 99000 cm3 (99L)
Distance from ocean: 4.5 m
Substrate: rock, sediment

#6 Big pool

Shape: Rectangle, 610 x 295 cm
Surface area: 179950 cm2
Average depth: 50 cm
Max depth: 65 cm
Volume: 8997500 cm3 (8998 L)
Distance from ocean: 1.1 m, 2.7 m
Substrate: Sand, rock, small rocks

#7 Stream pool

Shape: Rectangle, 80 x 30cm
Surface area: 2400 cm2
Average depth: 4 cm
Max depth: 6.5 cm
Volume: 9600 cm3 (9.6L)
Distance from ocean: 4.5 m
Substrate: rock

#8 Elephant pool

Shape: Rectangle, 36 x 85 cm
Surface area: 3060 cm2
Average depth: 53 cm
Max depth: 54 cm
Volume: 162180 cm3 (162 L)
Distance from ocean: 0.5 m
Substrate: sand

#9 Big crater

Shape: Semi-circle, diameter 230 cm
Surface area: 20773.78 cm2
Average depth: 11 cm
Max depth: 34 cm
Volume: 228511.58 cm3 (229 L)
Distance from ocean: 1.3 m
Substrate: Rock, small rocks

#10 High half-crater

Shape: Semi-circle, diameter 135 cm
Surface area: 7156.94 cm2
Average depth: 9.5 cm
Max depth: 13.5 cm
Volume: 67990.93 cm3 (68 L)
Distance from ocean: 1.2 m
Substrate: Rock, lichen

#11 Neptune’s crater

Shape: Rectangle, 40 x 25 cm
Surface area: 1000 cm2
Average depth: 4 cm
Max depth: 4 cm
Volume: 4000 cm3 (4 L)
Distance from ocean: 0.5 m
Substrate: Sand

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Big Pool, with a view towards the back of the Bluff, and the oft-inundated crab wall.

While these are only the initial observations for the Bluff, it was the beginning of many discoveries. Much of it is rehashed ground – the littoral zone is readily accessed and people have been doing so for the last 150 years, even in Australia. But for me it’s new. For Salty, it’s new. For Keen, even though he has always been a beach bum, there exists this entire other world just below the waterline. A world fraught with battles and courtship, a world where tiny creatures overcome enormous odds in the everyday fight for survival.

Join Salty and I again soon as we peer upon this miniature world, and discover some damned strange things washed up on the beach. Here’s an exclusive preview:

Dangerpus: “Just what is that weird white lumpy thing, Salty?”
Salty: “…”
Dangerpus: “It looks like some mass of anemones – or maybe sea spaghetti!”
Salty: “S:(”
Dangerpus: “Let’s bag it and take it back to the lab.”
Salty: “!”

*Over and out*

Part 2 here: Secrets of the Rock Pools

The Hunt for Life

Hidden life beneath the waves inspires a quest to uncover the ocean’s mysteries.

Waves foam on pale sand. In the shallows, children leap white crests. Pairs of mothers idle on the warm sand, and grandparents sit along the low wall spanning the south leg of the beach.

At the end of the walkway, the old pump house has been painted the same blue as the sky. Its barnacle-encrusted pipes extend 30 metres out into the ocean, terminating in a big green lump of cunjevois like a sunken tropical island. South of the pump house, low rocky cliffs split the beach in two. Black heads of surfers speckle the waves south to Sandon Point. Further north, far beyond the freshly painted, resplendent yellow surf club, a long rock shelf juts out beneath the striped masses of Austinmer cliffs.

Thirroul is a historic but thriving town planted between the ocean and the escarpment some 13 kilometres north of Wollongong. From its farming and coal mining origins, Thirroul has reinvented itself to cater to the well-to-do drifting down from Austinmer. Recently the old shoe shop, Buck Hamlin’s, was reopened as a cafe. The black painted brickwork of the Finbox surf shop are especially iconic, in the hazy afternoon sun fading into the dark bulk of the escarpment behind. In summer the beach is flooded with tourists and the locals complain of a dilution of familiar faces on the streets.

I fell in love with Thirroul Beach working at Rutledges’ garage, but it wasn’t until my brush with death that I became more interested in life beneath the waves. A beach can seem deserted. Yet underneath the surface there is such an abundance and variety of life that the mind can scarcely comprehend. All but the densest jungle on the surface is barren by comparison.

The Thirroul Beach survey will be my first marine survey and aims to uncover types and numbers of living organisms in the littoral regions. It’s a learning experience for me: six months ago I couldn’t tell a limpet from a barnacle. Exploring the beach has uncovered mysteries I never knew existed, and given me the motivation to live, and live a good life.

First to be surveyed is the supralittoral zone nicknamed Crab Bluff, just south of the pump house. Second will be the eulittoral/ intertidal zone on the northern rock shelf; and lastly forays will be made into the permanently inundated sublittoral zone, likely from the entrance point of the sandy beach.

In all zones, species will be identified and populations counted, water temperature, salinity and quality measured, interactions observed, and sea stars hunted.

Join me in the coming weeks for the hunt for life on Thirroul Beach.

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