Dual sex sea creatures swamp Far South Coast beaches

Bluebottles at North Durras. Photo: Christa White Facebook
Bluebottles at North Durras. Photo: Christa White Facebook

Locals and visitors have been returning beaches along the Eurobodalla and Bega Valley coastline, the chill of winter replaced with the temptation of a swim under big, bright, blue skies.

But that springtime enthusiasm has been tempered on some beaches with the mass arrival of familiar but alien looking creatures – Bluebottles.

Not one creature but many, these duel sex visitors to Far South Coast beaches are a collegiate group each with a job to do before being blown ashore.

“I love bluebottles, they’re awesome,” says Kerryn Wood, Manager of the Sapphire Coast Marine Discovery Centre in Eden.

“They’re actually a colony of several animals, all with specialised functions – feeding, catching prey, and reproduction.

“Fascinating!” Kerryn says.

A tangle of Bluebottles. Photo: Colin Eacott Facebook
A tangle of Bluebottles. Photo: Colin Eacott Facebook

According to the Australian Museum, the Bluebottle is a colony of four kinds of highly modified individuals known as zooids, and come from the same family of life that includes coral and sea anemones.

“The zooids are dependent on one another for survival.

“The float (pneumatophore) is a single individual and supports the rest of the colony.

“The tentacles (dactylozooids) are polyps concerned with the detection and capture of food and convey their prey to the digestive polyps (gastrozooids).

“Reproduction is carried out by the gonozooids, another type of polyp,” The Museum says.

Generally speaking, northerly winds bring Bluebottles onto local beaches.

“There have also been some pretty big seas lately,” Ms Wood says.

The beauty of Bluebotlles. Photo: Jackie Saunders Facebook
The beauty of Bluebotlles. Photo: Jackie Saunders Facebook

The Bluebottles famous float can grow to over 15cm, it’s job is to sail the colony across the ocean surface capturing the breeze with its aerodynamic shape. A degree of muscular contraction in its crest gives the Bluebottle a sense and skill similar to a holidaying windsurfer.

Local surfboat crews training for January’s George Bass Surfboat Marathon are reporting large “schools” of Bluebottles bobbing about at sea.

“The float may project either to the left or to the right; the left-handed forms sail to the right of the wind and vice versa,” The Australian Museum explains.

“Thus, if the sailing angle of one form leads to its stranding on the shore, the others sailing to the opposite side of the wind may escape.”

A neat survival trick that maintains the population even when Far South Coast beaches are blanketed in dried and popping specimens.

Food and reproduction drive life and Bluebottles have some impressive tools to call on.

Their stinging tentacles drift downwind for up to one metre capturing food in their wake, responding swiftly to the presence of food, they twist and tangle prey, and “become all mouth” to digest their meal.

A range of enzymes are deployed to break down proteins, carbs, and fats across a menu of small crustaceans and surface plankton.

Reproduction is another impressive Bluebottle trick that helps it’s species survive on the high-seas.

Bluebottles are hermaphrodites, they carry female and male parts.

“Awesome, I love that so many marine creatures are hermaphrodites,” Ms Wood says.

“And sometimes they’ll wash up on the beach with a variety of other really beautiful ‘blue’ animals like Glacus atlanticus or the Blue Sea Dragon – also hermaphrodites.

“The Glaucus atlanticus actually eat blue bottles and ‘steal’ their poison, making them even more poisonous!” Ms Wood says.

The Glaucus atlanticus, AKA Blue Dragon, eats Bluebottles. Photo: Commons Wikki
The Glaucus atlanticus, AKA Blue Dragon, eats Bluebottles. Photo: Commons Wikki

All this is very interesting but from a human perspective, avoiding the stingers and knowing what to do if stung is front of mind during a day at the beach.

Andrew Edmunds from the Far South Coast Surf Lifesaving Association says northeasterly winds and swells in particular bring Bluebottles on to beaches between Batemans Bay and Eden.

“Avoiding north-east facing beaches in those conditions might help families dodge Bluebottles,” Mr Edmunds says.

“The best treatment for a sting is hot water, a shower as hot as you can without burning does the trick.

“And if hot water isn’t available ice is a good alternative in relieving the pain after you have washed the tentacles away,” Mr Edmunds advises.

“Swimming at a patrolled beach this summer will ensure that first aid is close at hand from lifesavers.”

And be aware beachcombers, as thousands of Bluebottles lay shipwrecked on local beaches the toxic mixture they use to immobilise and digest their prey is still active and can sting you, however the contractions that trap their marine victims becomes inactive.

Bluebottles are awesome, the sting they can inject into a day at the beach instinctively demands our respect, but so to should their survival skills.

*Become a member of About Regional and support local news and stories, thank you to the Bega Valley Regional Learning Centre, Linda Albertson, Julia Stiles, Ali Oakley, Rosemary Lord, and Simon Marnie.

*Large elements of this article originally appeared on Riot ACT.

Tathra Wharf recycled into a new future following monster seas

The sun rises on Tathra Wharf, photo from The Wharf Locavore
The sun rises on Tathra Wharf, photo from The Wharf Locavore

The record-breaking seas that slammed into the much loved Tathra Wharf in June 2016 have opened a new chapter in the history of this 150-year-old structure.

The timber that was salvaged from the wrecked sections of decking and pylons has been snapped up with a sense of reverence. A host of upcycled projects has been born spreading the affection for this Far South Coast icon.

Over the weekend of June 4 and 5 2016 waves of up to 17 meters high or more shattered timber and fixtures that had stood the test of time.

Protected from the more frequent rough weather of the south, the wharf was at the mercy of this north-easterly inspired weather event.

On the Monday morning that followed Bega Valley Shire Council confirmed that the timber ramp that leads from the roadway down to the old cargo platform had been lifted off its pylons by the monster seas.

A repair job estimated to be worth half a million dollars was launched, recognising the importance of this pinkish structure to the region’s tourist appeal and sense of identity.

Click on each photo to get a bigger view…

Any timber that could be repurposed at the wharf was, with poor decking in undamaged sections replaced with suitable timber from the damaged sections.

Some of the larger scale timbers salvaged remain in the Bega Valley Shire Council stockpile, ready for maintenance works on the 70 timber bridges that dot the shire.

The remaining timber was offered to the volunteers at the Tathra Wharf Museum.

Museum Secretary, Michelle Russell says the organisation has been able to sell some of the leftover timber as a fundraiser with some pieces seen as being sculpturally interesting.

“A lot of the timber has been sold to woodworkers,” she says.

Michelle has been surprised at the interest after first thinking the timber would be sold as firewood for winter.

“It’s a bit of history and that seems to be what people want,” she says.

Most of the load has been sold off, earning around $1500 for the museum. Some pieces have been kept as museum exhibits while others will end up keeping local homes warm during the months ahead.

Anthony Little, owner of Fat Tony’s Resturant on the hill above the wharf was one of those to snap up a chunk of Tathra Wharf.

“I remember climbing on the frame of the wharf as a kid and running down to see sharks pulled in by fisherman,” Ant says.

Three obscure hunks of rusted timber now sit in the front yard of Ant’s eatery, which was the former residence of the Tathra Harbourmaster; the last ship to take cargo from the wharf was the SS Cobargo in 1954.

“I’ll be putting up some display boards and mounting each piece properly to highlight the connection between this place [the harbourmaster’s residence] and the wharf,” Ant says.

Craftsman like Greg Wall and Peter Hull have given the salvaged timber a new use altogether.

“Some of this timber has seen 150 years of traffic, it’s too good for firewood,” Greg says.

The woodworker from Black Range has turned a mix old stringy bark, iron bark, and gray box into a mortise and tenon joint bookcase for the wharf museum.

“I wanted to construct the bookcase using the skills of the time, the skills of 150 years ago when the wharf was built,” Greg explains.

Tarraganda joiner, Peter Hull says it’s been a thrill working with such significant timber and turning it into vanity benchtops and mantle pieces.

“My clients have loved being able to share the story behind their new feature,” Peter says.

Click on each photo to get a bigger view…

Apart from using its stockpiled timber in bridge structures, Bega Valley Shire Council plans on using some of its Tathra Wharf stash to make street furniture and gateway signage at the northern, southern, and western entries to the shire.

Some of the turpentine has already found bums in need of a seat in the Merimbula CBD and on the very structure it came from.

On her sunny verandah in Jellat, Museum Secretary, Michelle Russell is just happy to have a few lumps of the wharf to sit pot plants on.

“I have a family connection, Daniel Gowing was one of the first people involved in constructing the wharf,” Michelle says.

“I would like to thank Council for giving us [the museum] the timber because it’s been a great fundraiser,” she says.

“We haven’t decided what we are doing with the money yet, but we have a few projects in mind.”

Click on each photo to get a bigger view…

Apart from the acute damage that resulted from the East Coast Low of June last year, further assessments uncovered defects in 22 of the wharf’s 78 pylons. More work is needed to secure the structure’s long-term future especially in the face of increasingly testy seas.

Bega Valley Shire Council and the NSW Government are considering their options.

“We figure it’s been there a long time and will continue there for a long time yet,” Michelle Russell says.

“Mostly because the community considers it to be so important, it’ll be there in another 150 years I am sure.”

For those who don’t have a piece of Tathra Wharf as their own yet, small chunks are available for purchase from the Tathra Wharf Museum, which is open 10am to 4pm Saturday and Sunday.

 

 

Disclaimer – author is part time media officer for Bega Valley Shire Council.

 

 

 

 

 

 

 

 

Glowing oceans and starry skies: Bioluminescence at Mallacoota

Sailing at Mallacoota. By Kate Burke
Sailing at Mallacoota. By Kate Burke

Warm summer nights, beach dreaming, magical skinny-dips in sparkling coastal lakes…and with every kick and splash, the dark water around us lights up like magic.

Many of us describe it as “phosphorescence”, but it is something more exciting than a mere glow – it is bioluminescence, evidence of tiny marine creatures and their remarkable way of shining a light on their predators.

Tonight, my man Pete and I are counting our lucky stars (figuratively – there are millions visible) as we leave the kids with Pete’s parents and head out in our little Investigator trailer sailer to spend the night by ourselves on Mallacoota Inlet.

Motoring through the narrow passage from Mallacoota Wharf to the main lake, red port markers blink to our left, green to our right, and up ahead the bright white beacon marking the channel entrance.

As we move away from the town, a waxing sliver moon sets behind the warm lights that glow from living-rooms and verandahs to the west.

The lake darkens, and as we set our sails and switch off the motor we are somehow sailing by the light of Venus and the Milky Way.

Even the tiniest light source suddenly seems alive, powerful, attractive.

The sky and the storms out on the far horizon are also alive. So alive that as we gaze at them as our keel runs aground on soft lake mud and we’re suddenly without steering. So alive that it happens again about ten minutes later. So alive that it takes us a good while to notice the bright green streams of water stretching out behind the rudder and fanning out like wings from the bow of the boat.

Bioluminescence at the Gippsland Lakes. By Phil Hart
Bioluminescence at the Gippsland Lakes. By Phil Hart

Pete and I tied our boat up to a jetty in ‘The Narrows’. I dropped a rock in the water. Light spattered like sparks – at first on the surface, but then settling into a gentle twinkling that revealed a sparkle all through the water.

Stars twinkled above, and the lake was its own galaxy of billions of lights, off and on, tiny.

Then we saw the hive of fish activity along the shoreline. Flickering of tails, each movement trailing a shower of light. Splats and runnels of luminescence. All movements, the paths of all living lake life, traced in shining light.

Tiny plankton known as dinoflagellates, the food of many whales, emit light – not phosphorescence but rather bioluminescence – in a clever play, a kind of lure.

But why draw attention to yourself, little plankton?  Why be a target?

It seems that it’s about a chain of events. Tiny plankton are hunted by predators such as crustaceans, and crustaceans are hunted by larger creatures such as big fish.

When crustaceans move to attack plankton, the plankton light up – “over here, over here!” – larger predators are attracted by the commotion and make a good feast of the crustaceans, effectively taking care of the plankton’s predators.

Dinoflagellates feed on algae and other plankton, and their populations can grow when there are high nutrient levels in coastal waters.

Bioluminescence is not limited to tiny organisms;  in fact, there are bioluminescent species of sharksAnd bioluminescence can hide some species instead of attracting attention (as described in the wonderful kids’ science book The Squid, the Vibrio & The Moon).

According to Ferris Jabr of Hakai Magazine, bioluminescent crustaceans called ostracods were dried for storage by Japanese navy personnel during the Second World War, then made into a paste and used as a covert light source for reading maps.

But here at Mallacoota, it’s the tiny plankton who are shining a light on their predators.

Pretty darn cool, sadly too cool for a midnight swim. Maybe another time.

All the same, Mallacoota Inlet is a stunning place to wake up.