Newsletter: Weathered

Hi divers

Weekend dive plans

SaturdayStudent and Refresher dives at Long Beach from 9.00 am

I am having a tough time trying to understand the current weather. Despite days of westerly and north westerly wind the visibility has been very very slow to respond. At Long Beach the visibility today was only 3 metres. It should have have been better.

There is more wind, coming from the right direction, forecast for tomorrow so I am hoping for better viz by Saturday. I have student and Refresher dives to do so I will be at Long Beach from 9.00 am.

Yacht at Long Beach
Yacht at Long Beach

Clipper Yacht Race news

The Clipper Yacht Race vessels are arriving in Cape Town at the moment, and you can visit them at the V&A Waterfront. There are several excellent events planned while the yachts are here.

There’s also a talk about this round the world race at Hout Bay Yacht Club next Wednesday, 25 October, at 7.30 pm. Details here (on facebook).

regards

Tony Lindeque
076 817 1099
www.learntodivetoday.co.za
www.learntodivetoday.co.za/blog/

Diving is addictive!

To subscribe to receive this newsletter by email, use the form on this page!

Bookshelf: Other Minds

Other Minds: The Octopus, the Sea, and the Deep Origins of Consciousness – Peter Godfrey-Smith

THIS is the octopus book you have been waiting for all your life. Philosopher of science (and, importantly, scuba diver) Peter Godfrey-Smith traces the origins of intelligence through the tree of life, pausing at length on the cephalopods. These animals – cuttlefish, octopus, squid – stand out as exceptionally intelligent among animals, but only live for a year or two, the females expiring after they finish nurturing their first and only clutch of eggs (this is called semelparity). Both they and the males undergo a brief and catastrophic period of senescence, during which time they lose limbs, lose pigmentation, and their cognitive functions appear to be in sharp decline. (As an aside, I think that this cuttlefish may have been experiencing this very late-life decline.) Why, speaking evolutionarily, invest the energy required to develop such a complex brain, if its owner is going to live for such a short time?

Other Minds
Other Minds

This is the ultimate question that Godfrey-Smith grapples with. Prior to arriving here, he leads us on wonderful explorations of octopus physiology, the origins of life, and the nature of intelligence. Refreshingly, he takes a nuanced view of intelligence in cephalopods and resists the ever-present temptation to anthropomorphise these fascinating creatures. He points out, for example, that it is easy to mistake dexterity – eight arms and all – for smarts. I read this book while recuperating from a head injury whose degree of seriousness was not yet clear at the time of reading (it was mild, and I’m fine now). This uncertainty as to the state of my own brain made my reading of the sections on intelligence and the nature of minds somewhat poignant. The octopus brain is distributed throughout its body, with neurons in its legs as well as in places you’d be more likely to look for them.

Godfrey-Smith commences this book with a description of giant cuttlefish (the same corgi-sized beings we read about here), and this cements my desire to one day meet such a creature. My favourite chapter, however, deals with how cephalopods change colour. The complexity of this process is incredible, and not yet fully understood. In particular, it seems that they cannot see in colour, and yet they perform feats of camouflage that would seem to be impossible without knowing what colour and pattern to aim for.

The book is beautifully, lyrically written with a gentleness and compassion that I think comes from Godfrey-Smith’s own extensive observation of cephalopods in their natural habitat. He returns compulsively to Octopolis, the first octopus “city” discovered off the coast of Australia. I’ll leave you with this quote:

The chemistry of life is an aquatic chemistry. We can get by on land only by carrying a huge amount of salt water around with us.

You can find a comprehensive list of reviews and interviews on the author’s website. There’s a fetching giant cuttlefish picture in this article from The Guardian. If you are in South Africa, get a copy of the book here. If in the US, here, and for the UK go here.

For an equally awe-struck but completely different take on octopus, written largely from the perspective of an aquarium volunteer, you could also check out Sy Montgomery’s The Soul of an Octopus.

Shrimp news from False Bay

The University of Cape Town has announced that a further three new species of shrimp, all spotted close to shore near Millers Point in False Bay, have been described and named. All three belong to the same genus (Heteromysis), and look similar, with pale bodies marked by red spots and stripes. One of these new (to science) species lives inside octopus dens, and another lives inside the shell of certain types of hermit crab. These three shrimps join the stargazer shrimp that was discovered by and named for Guido Zsilavecz, citizen scientist and author of several books on False Bay’s marine wildlife.

Two of the new species were discovered by local film maker Craig Foster, founder of the Sea-Change project about which we read last week. These types of discoveries are very exciting and should be a great inspiration and encouragement to divers and other water users. Time in the water is rewarded. If you can’t identify something, send an email with its photo to SURG. It is possible to make significant contributions to science while holding down an entirely non-scientific day job!

Read all about the new shrimps here.

Cape Town’s visible shipwrecks: Update on the Commodore II

Until recently, the last time I specifically went looking for the wreck of the Commodore II was in December last year, when I went to Milnerton lagoon beach to show visiting family the beautiful view of Table Mountain. At that time tides and waves had moved the wreck further away from the lagoon mouth, and she was lying on the sand at a spot that would be partially submerged at high tide.

There has been some community discussion about the future of the wreck since late last year, but nothing changed until winter arrived.

Commodore II in December 2016
Commodore II in December 2016

Next time I went to look for the wreck, just after the Cape storm of 7 June this year, I couldn’t find it. A waiter at the Wang Thai restaurant on the beach told me he’d seen it all the way up at the old Wood Bridge at Woodbridge Island, and that people were removing pieces of the wreck and carrying them away. The storm surge had actually lodged the wreck partially under the old Wood Bridge (a sensitive National Monument constructed in 1901), and there was the potential for it to cause damage. There’s a picture of the wreck in this position on page 28 of this document (pdf).

Commodore II, secure for now
Commodore II, secure for now

A few weeks ago Gerhard Beukes, a Milnerton resident, messaged me to say that he had secured the wreck about half way down the lagoon. It had been winched free of the Wood Bridge by Koos Retief, Area Biodiversity Manager at Table Bay Nature Reserve, and had floated back down the lagoon to settle on a sandbank near Gerhard’s home.

Gerhard estimates that the wreck weighs about 25 tons, and with considerable personal effort and some financial outlay he has attached it to the lagoon bank, resting on the sandy bottom in shallow water, with chains and heavy lifting straps. The chain is secured to bolts attached to metal pipes sunk deep into the bank.

The Commodore II in Milnerton
The Commodore II in Milnerton

The arrangement will prevent the wreck from washing around inside the lagoon and potentially injuring kayakers and other water users. It will also prevent it from washing out into Table Bay and becoming a semi-submerged shipping hazard, potentially lethal to vessels (something like the Seli 1 is when her buoy goes missing).

View towards Woodbridge Island
View towards Woodbridge Island

It’s also quite visible: if you walk or drive down Esplanade Street in Milnerton with Lagoon Beach behind you, you’ll come across the remains of the Commodore II next to the bank of the lagoon on your left. The wreck is over 60 years old, which means that under South African law it is protected and removing pieces of it is an offence. I hope that having many local residents’ eyes on the wreck will ensure it some measure of safety, even in the absence of any enforcement of the relevant laws.

How can you help?

To make sure the wreck does not come loose next time a large volume of water washes down the river and into the lagoon after heavy rains, it needs some further reinforcing in its current location. This could be done with a further 5 metre length of heavy duty chain, or (preferably) two loading slings, 25mm steel cable with rings or eyes on both ends. The harness needs to be capable of holding 25 tons of wood in place even under strain, and are necessary to completely stabilise the wreck.

If you have such items lying around unused at home, or are sufficiently moved and interested by the wonderful history of the Commodore II to make a donation, please comment on this post or use the contact form here, and I’ll connect you with Gerhard, the current guardian of the Commodore II.

Are you interested in shipwrecks that you can visit without going underwater? Read more about Cape Town’s visible shipwrecks here.

Newsletter: Keeping current

Hi divers

Weekend dive plans

No diving

We dived Long Beach today in surge, strong current and lousy visibility. It is full moon and we have had some swell but I was hoping it would be ok – it wasn’t.

Weekend conditions do not look ideal for recreational (fun!) diving. Better luck next week I hope.

Rock lobster munching a sea jelly
Rock lobster munching a sea jelly

Date to diarise

There’s a talk on South Africa’s inshore marine resources, with special reference to West Coast rock lobster stocks, happening on Wednesday 18 October under the auspices of Kommetjie Environmental Awareness Group. It starts at 7.30pm at Kommetjie Christian Church. There’s a blurb with more info here. It should be an extremely interesting event, and I’d particularly encourage you to attend if you are a keen crayfisher in season…

regards

Tony Lindeque
076 817 1099
www.learntodivetoday.co.za
www.learntodivetoday.co.za/blog/

Diving is addictive!

To subscribe to receive this newsletter by email, use the form on this page!

Article: Exploring False Bay’s kelp forests

Kelp forest in Sandy Cove
Kelp forest in Sandy Cove

Environmental journalist Pippa Ehrlich writes beautifully for Safarious of diving in the kelp forests of False Bay with Sea-Change founder Craig Foster. You might be familiar with Sea-Change from an exhibition at the Sea Point promenade a couple of years ago.

The idea of getting into this freezing world every day without a wetsuit was daunting. We did some stretching and breathing to warm up. The sky was grey and my feet had gone numb in the shallow water we’d had to walk through. I was not looking forward to being fully submersed in it.

Ehrlich and Foster (and others from the Sea-Change team) dive daily in False Bay, sans wetsuits. It is their mental (spiritual?) approach to the marine environment, however, that sets the project apart. It’s a mindset that may be unfamiliar to many divers, especially those of us who favour scuba, but it is worthy of serious consideration. The article reads like a story of love and healing.

The accompanying photos are beautiful, too. Read it.

Diving in the I&J Ocean Exhibit at the Two Oceans Aquarium

The I&J Ocean Exhibit is the largest tank at the Two Oceans Aquarium, and has been open since mid-2016. It features a full 10 metre long tunnel, and is home to Yoshi the turtle, two green turtles, bonito, musselcracker, a guitarfish, some rays, and several other species. Watching the animals being fed at 12pm on a Sunday is a highlight of my monthly shift at the aquarium.

Yoshi the loggerhead turtle
Yoshi the loggerhead turtle

I needed to dive in the tank, and Tony and I were lucky to be escorted by the wonderful Angie, who has been a Divemaster at the aquarium for several years. The dive is easy: the tank is shallow, warm, and the visibility is to all intents and purposes limitless. Angie pointed out that in an out of air situation, we’d just do a CESA to the surface. (This makes the aquarium perhaps the only location you’d use this skill in its pure form…) The animals aren’t dangerous, but they need to be respected, and the soft acrylic windows pose a particular challenge as a careless bump with some dive gear would scratch them from the inside.

Angie and Bob the green turtle
Angie and Bob the green turtle

The green turtles are special. Bob was found in poor shape on the beach at De Hoop when he was the size of a dinner plate, and after several months in intensive care, regurgitated a quantity of plastic, including ribbons and balloons. Now, he is friendly and very attached to humans – he especially loves to have his shell tickled, and wriggles from side to side in appreciation. As a result of the amount of time he spent in veterinary care, he will stay at the aquarium for his own safety.

Tony and Sandy the green turtle
Tony and Sandy the green turtle

Sandy was most likely struck by a boat propellor near Witsand at the mouth of the Breede river. The scars are visible on her carapace in the photo above. She was recently discovered to be definitely female (turtles are tricky). She’s not quite as interested in humans as Bob is, but she was mesmerised by her tiny reflection in Tony’s camera lens, and approached closer and closer to examine it.

The giant guitarfish
The giant guitarfish

In addition to the turtles, Tony enjoyed the fantastic giant guitarfish, and spent much of the dive looking for it. The rays are like puppies, full of youthful exuberance and energy. The schooling fish mostly keep out of the way of the divers, near the surface of the tank, but are a treat to be close to.

We last dived in the aquarium a couple of years ago. The kelp forest, which was an enormously enjoyable dive, is currently closed for renovations but will be re-opening soon. The new shark exhibit will also be open for dives soon (it is already open for looking at, with nine ragged tooth sharks in residence). Meanwhile, the Ocean Exhibit provides more than enough diversion on a day that doesn’t offer good enough weather for a sea dive.

Dive date: 29 April 2017

Air temperature: 30 degrees

Water temperature:  24.8 degrees

Maximum depth: 6.1  metres

Visibility: 15 metres

Dive duration: 36 minutes

Newsletter: Fishy conditions

Hi divers

Weekend dive plans

No diving

We have just returned from Sodwana, where we did a few eventful warm water dives with Coral Divers. If you haven’t been to Sodwana you should add it to your diving bucket list, for the colourful, vibrant reefs and good visibility. Highly recommended.

A barred rubberlips at Pinnacles
A barred rubberlips at Pinnacles

Local diving is not looking too promising for this weekend. A strong south easterly wind arrives on Friday night and departs on Sunday night. This is not really ideal for diving False Bay. Hout Bay is currently green and swelly, and will need several days to clean up.

My recommendation – if you must get wet – is that you consider diving in the I&J Oceans Exhibit in the Two Oceans Aquarium (blog post about this coming on Monday) and see the loggerhead turtle, Yoshi. She is to be released later in the year – read more here.

regards

Tony Lindeque
076 817 1099
www.learntodivetoday.co.za
www.learntodivetoday.co.za/blog/

Diving is addictive!

To subscribe to receive this newsletter by email, use the form on this page!

Newsletter: On and off

Hi divers

Weekend dive plans

DIY diving!

Kite surfers at Muizenberg
Kite surfers at Muizenberg

False Bay has been on and off this week. The swell is not wicked but it’s there and noticeable. The weekend does not look terrible, but we will leave the choice of diving or not up to you… We are heading north in search of warmer water. We are back in town next week Friday and will be ready to dive.

regards

Tony Lindeque
076 817 1099
www.learntodivetoday.co.za
www.learntodivetoday.co.za/blog/

Diving is addictive!

To subscribe to receive this newsletter by email, use the form on this page!

Newsletter: In the zone

Hi divers

Weekend dive plans

Sunday: Boat dives or Long Beach dives, depending on conditions

We seem to have fallen into a weekday diving zone where conditions are good for a few days during the week and then the weekend comes and the wheels fall off.

There is a lot of swell and wind in the forecast as well as some abrupt wind direction changes. This all makes for “look before you go” type planning that hardly works well. Saturday is definitely out. Sunday will depend on how bad Saturday is, and we will make the call on Sunday morning.

Langebaan lagoon
Langebaan lagoon

As a last resort we may opt for a Long Beach dive as it is somewhat sheltered.

Diversnight

We got the date wrong last week. (It’s correct here.) Diversnight is on Saturday 4 November this year. Diarise!

regards

Tony Lindeque
076 817 1099
www.learntodivetoday.co.za
www.learntodivetoday.co.za/blog/

Diving is addictive!

To subscribe to receive this newsletter by email, use the form on this page!