Tim the Yowie Man: Curious cuttlefish

While the inquisitive Sledge asks, "why do we see more cuttlebones on our beaches at this time of year", Wilson wonders "we only see their bones, but what exactly does the cuttlefish look like when it's alive?"

In order to answer these two questions, during the week your akubra-clad columnist pulled out the boardies from the bottom drawer, did the "slip slop and slap" and made a beeline to the coast.

First stop was the beach. Although restricting my "scientific" surveys to just three beaches (yes, I know it's a tough job), namely Tomakin near Batemans Bay, Tuross Head and Merimbula Surf Beach, as predicted by Sledge and Wilson, all were littered with the familiar white bones of the ubiquitous cephalopod.

To help solve the mystery of the significant numbers of cuttlebones, I enlisted the assistance of Bill Barker, a member of the Nature Coast Marine Group and celebrated cuttlefish aficionado.

Barker believes the reason for the high numbers of bones on our beaches at this time of year is simply due to their reproduction cycle. "They breed in July and following mating the male and females soon die, meaning their bones are often washed up on the beach in late spring," explains Barker.

Also an avid diver, Barker regularly braves the frigid winter waters off Potato Point (just south of Tuross Head) to witness "the males engaging in a spectacular ritualised combat to impress watching females."

"It's a magical experience to share the water with these wonderful creatures, just drifting back and forth in the surge with this display going on right in front of you, sometimes so close that they brush up against you," marvels Barker, adding "I've also seen them doing this once while snorkelling, just a few metres from the shore."

This mating season Barker even managed to catch the protracted courtship display on film.

"You press your record button on the video, leave it on a rock and let it run until the battery runs out," says Barker, adding "eventually the winner of the combat impregnates the female which then lays eggs that produces tiny replicas of their parents."

According to Barker, "after mating the mum and dad fade away and die, often ending up, several months later, as the cuttlebones spotted on the beach."

"While many of the cuttlebones on our beaches are only 10-15 cm long, occasionally you'll find an extra big one which belongs to the Australian Giant Cuttlefish (Sepia apama) adds Barker.

In fact, attached to the aforementioned correspondence from Phill Sledge, of Kaleen, was this photo of "a larger than normal" cuttlebone he recently found on Tomakin Beach. Although Sledge didn't have a tape measure on hand, his photo reveals his discovery was "as long as his size 9 thong".

Gloating about his chance find, Sledge has laid down a challenge to other readers "to uncover an even bigger cuttlebone this summer".

Please send you entries (preferably measured with something a little more accurate than a thong!) to the address at the end of this column.

Cuttlefish: The Australian Giant Cuttlefish (Sepia apama) has been recorded over 40cm mantle length and more than 5kg in weight. More common, smaller species rarely grow more than 20cm mantle length.

Not a diver? You can still see live cuttlefish at the Merimbula Wharf Aquarium Restaurant (www.merimbulawharf.com.au).

Did You Know? The giant cuttlefish has ten 'arms', of which two are feeding tentacles that are used to grasp prey.

Tim's Tip: The giant cuttlefish is a master of camouflage, and is able not only to change its colour but also the texture of its skin.

Don't miss: Bill Barker's video footage of two male cuttlefish courting a female, filmed in about eight metres of water off Potato Point. https://youtu.be/GJinm-jR_MI

Further afield: If you want to witness Cuttlefish en-masse then head to the Spencer Gulf near Whyalla in South Australia where each winter over a quarter of a million individuals aggregate for mating. "This is the only known dense spawning aggregation of cuttlefish in the world," states Professor Bronwyn Gillanders, of the School of Biological Sciences at the University of Adelaide, adding "that's literally one fish per square metre." Wow, what a spectacle that would be.

Although cuttlebones are collected by pet owners as calcium-rich dietary supplements for caged birds, reptiles and snails, they also have an eclectic range of historical uses including in traditional Chinese medicine as treatments for ulcers, and also to make toothpaste.

One enterprising south coast resident also handcrafts sterling silver jewellery cast from carved cuttlebone collected from her favourite beach. "Each piece is unique as the cuttlebone mould is destroyed in the casting process," explains Rachel McInnes, of Potato Point.

To ensure she has a sufficient supply of cuttlebones, McInnes has even enlisted the help of her friendly neighbours. "When locals find cuttlebones washed up on the beach they leave them on my front verandah for me!" exclaims McInnes.

You can view a selection of McInnes' jewellery at her website. I especially like the whale tails, which provide a tangible reminder of the majestic marine mammals which migrate south along this section of coast each spring.

I must have been a good boy this year, for Christmas came early for me this week with the re-release of the long out of print environmental classic Back Country: Trek through the Deua and Wadbilliga (John Blay, Canopy Press).

First published in 1987 Back Country documents Blay's epic trek through what are now Deua and Wadbilliga National Parks, all the way from Araluen to Bemboka. Through his sensitive observations and engaging prose Blay shines the spotlight on the region's rare wildlife, falls, gorges, caves, gold diggings, Aboriginal sites, and even fabled yowie haunts.

Blay's research and travels in the region have continued over the years, resulting in this much-revised and updated exploration of the rugged parts of the south-eastern ranges.

Those lucky enough to have read the first edition of Back Country will especially relish in Blay's "Afterword" in which he articulates the pivotal role "Back Country" played in his maturity as an author. You may also feel a tinge of sadness when you discover the grisly end to the life of Zachary B. de Mule, Blay's beloved four legged companion which accompanied him on his original epic trek, and whose skeleton was found high in a tree after a flash flood.

A great Christmas stocking filler for anyone who appreciates the "wild" in wilderness.

Back Country is available at all good bookshops and online. The book's south coast launch will be held at Log Cabin, Eden from 3pm on 10 December.

Did You Know: During his trek through forests of our south-eastern escarpment country, Blay discovered a new species of wattle. The "Brogo wattle", which features flowers of a deep golden colour has since been named Acacia blayana in his honour.

Geologist Doug Finlayson has answered this column's recent call for local examples of columnar jointing, similar to those which woo tourists at the Giant's Causeway in Northern Ireland (Cryptic Causeway, November 12).

"The best examples in the Canberra region are at Ginninderra Falls gorge," says Finlayson. "The Ginninderra Porphyry is a high level stock that intrudes into the Laidlaw Volcanics, dating back 424-422 million years."

However, budding geologists wanting to visit the site will have to settle for viewing Finlayson's photo, for unfortunately due to public liability insurance reasons the privately-owned 42 metre high falls and surrounds remain off limits to the public.

Meanwhile, the origins of the stony sculpture located outside of 219 London Circuit in Civic, and which resembles Northern Ireland's Giant's Causeway, remains a mystery.

The only lead to-date has come from Kevin Mulcahy, of Tura Beach, who reports "the sculpture doesn't appear in a 1981 book published by the National Capital Development Commission (NCDC) titled Works of Art in Canberra which covered just about all the works of art in the place at that time."

Mulcahy's lead obviously suggests the sculpture was likely installed post-1981. Someone must know.

Clue: 'Pongy'

Degree of difficulty: Medium

Last week: Congratulations to John Hagan, of Waramanga, who was first to correctly identify last week's photo, sent in by Gabriel Garrigues, of Giralang, as "a view from the Butters Bridge, apparently one of the longest in the southern hemisphere, which spans the Molonglo River just downstream of Coppins Crossing". The bridge is named after Sir John Henry Butters (1885-1969) who was the first chief commissioner of the Federal Capital Territory (1925-1929).

Like many readers, Hagan, who just beat a stampede of other readers to the prize, including Sylvia Jordan and Richard Finch, of Palmerston, expressed disappointment at the design of the 25 metre tall and 242 metre long sewer piper carrying – cum-pedestrian bridge. "The high safety grill running along the entire length takes away enormously from the view over the river," he laments.

However, of over 50 readers (and counting) who fired off missives criticising the bridge's design, none were more damning than Penleigh Boyd, of Reid, who asserted "there must be a million ways to design a beautiful pedestrian bridge - but this isn't one of them." If you want to check-out what all the fuss is about, the Butters Bridge is best accessed via a path from the Coppins Crossing car park.

How to enter: Email your guess along with your name and address to timtheyowieman@bigpond.com. The first email sent after 10am, Saturday November 26, 2016 with the correct answer wins a double pass to Dendy cinemas.

CONTACT TIM: Email: timtheyowieman@bigpond.com or Twitter: @TimYowie or write c/- The Canberra Times, 9 Pirie Street, Fyshwick. You can see a selection of past columns here.