Starfish – Page 2 – Learn to Dive Today Blog

Dive sites (Southern Mozambique): Drop Zone

Loggerhead turtle at Drop Zone in southern Mozambique

Drop Zone is a newish reef in Malongane Bay, and was the first dive we did. The surf launch was uneventful and even enjoyable. Either I’m growing a pair, or our skipper Wayne was a master at reading the waves, or a combination of both effects was at work. We saw dolphins almost as soon as we left the beach, and watched them from a distance for a while. The dive itself was a bit of a shock to the system: we dived for over an hour, surfaced with air to spare, and didn’t even notice the water temperature (which, after diving in Cape Town, means it was very comfortably warm). There were also large creatures all over the place, magnificent coral, and some tiny stuff to reward close scrutiny of the reef.

Gorgeous little (unidentified) nudibranch at Drop Zone

It was my first dive with my new Ikelite AF35 strobe, and I was a little anxious that I’d have a wonderful dive but nothing to show for it as I fumbled around, blinding the divers with curious directional choices for the strobe arm. Fortunately I got the hang of it fairly quickly, and actually got some half decent results. Magnificent visibility provided much assistance. You’ll see that the picture of the moray eel is a bit washed out, as positioning the strobe when the subject is close up is something I haven’t fully mastered yet.

I was thrilled to see cowries – lots of them. As a child we’d find empty (small) cowrie shells on the beach at Betty’s Bay, and they’ve always had more value to me than other shells. These molluscs can cover almost their entire shells with their soft feet, and their shells are usually very shiny. Cowries are either male or female (for creatures of that level of complexity this is quite unusual) and our Divemaster told us not to touch or move them because then they’d lose their mates. I’m not sure whether they are faithful to each other like that, but not touching stuff is important here.

Dive date: 8 May 2012

Air temperature: 24 degrees

Water temperature: 25 degrees

Maximum depth: 13.8 metres

Visibility: 15 metres

Dive duration: 65 minutes

Bookshelf: The Edge of the Sea

The Edge of the Sea – Rachel Carson

The Edge of the Sea completes the trilogy begun by Under the Sea-Wind and The Sea Around Us. Its focus is on the coastline, the meeting point between land and ocean where one is most conscious of the passage of time and the cycles of nature. Rachel Carson was an American writer, and lived and worked on the east coast of the United States. The northern reaches of this coast are similar to the Cape Town coastline, in that there are kelp forests and much invertebrate life in the cool water. Its southern reaches in the Florida Keys, however, are characterised by coral reefs and mangrove forests, more reminiscent of Sodwana Bay in KwaZulu Natal, on South Africa’s north western coast.

This is a more conventional piece of nature writing than Under the Sea-Wind, and its scope is far narrower than The Sea Around Us. It is fascinating, however, to delve into the secret lives of crabs, sand fleas, limpets, urchins, sea stars, clams and a large number of their neighbours. While – for the most part – we don’t find the exact same creatures on our side of the Atlantic, their adaptations to life in the intertidal zone are similar, and their behaviour and diet is too.

The section on the coral reefs and mangroves of Florida was interesting to me because that kind of coastline is relatively unfamiliar – I’ve only visited coral reefs three times (Zanzibar, Sodwana twice) and don’t know nearly as much about how those ecosystems work. It was the first time someone articulated for me a point that – in retrospect – is probably completely obvious to everyone else on earth, but for me was a lightbulb moment. Coral reefs only occur on east-facing coasts (think about the location of the Florida Keys, the Great Barrier reef in Australia, the east African coral reefs), as the western coasts of continents are typically subject to upwelling driven by wind and the direction of the earth’s rotation.

Rather than being an active participant in the life of the shore, man is portrayed here as an observer, unable to influence the tidal and seasonal rhythms that drive all behaviour here. The book is illustrated with beautiful line drawings and one or two maps, and I’d recommend it highly. There’s a comprehensive glossary with full species names at the back.

You can buy the book here, or for Kindle get it here.

Sea life: Brooding cushion star

The first time I spotted a brooding cushion star, on an eye-wateringly cold dive on the SS Maori, I was reminded of nothing so much as a cupcake or similar edible baked good. These sea stars are fairly rare (according to A Field Guide to Marine Animals of the Cape Peninsula) and are found all around the South African coastline. When threatened they apparently secrete mucous to deter their predators.

These sea stars have a soft outer skin that is supported by a layer of spines, beneath which lies another layer of skin. The space between the two skins is used as a brooding chamber for eggs, and once the eggs have hatched the young sea stars emerge from a ventilation hole on the top of the mother. Prior to the eggs’ hatching, the ventilation hole is used to suck in and expel water which aerates the eggs.

Brooding cushion star on 13th Apostle reef

I saw another of these tasty-looking sea stars on 13th Apostle reef, also in the Atlantic. I haven’t seen one in False Bay yet.

Dive sites: Steenbras Deep

On Sunday 11 March, since the Cape Argus Pick n Pay Cycle Tour was going to prohibit access to basically the entire peninsula, we decided to take an expedition out to the eastern side of False Bay to do a boat dive with Indigo Scuba, run by Kate and Deon Jonker. We’ve been meaning to do this for ages and ages, so we were very glad to finally get ourselves over there! The southeaster (which had blown strongly in the few days prior to the 11th) actually cleans up the eastern side of False Bay while it messes up the western side, or at least has some positive effect on visibility. So while we are diving in the Atlantic during the summer, Indigo launches out of Gordon’s Bay and explores local dive sites such as Pinnacles, Cow and Calf, and the Steenbras River Mouth.

Deon Jonker skippering the Indigo Scuba dive boat

We met at Indigo Scuba in the morning, loaded up the boat, and then drove the 5 minutes to Harbour Island in Gordon’s Bay, from where we launched. It’s an extremely civilised launch site and overall experience… The foul-mouthed snoek slinging fishermen crowding Miller’s Point seemed like a bad dream!

It’s about 11 kilometres from Harbour Island to Steenbras Deep, and one has the feeling of being quite far out to sea – although we could see the mountains surrounding False Bay on both sides of us. The wind was stronger than the weather man had predicted, giving rise to some quite serious wind chop and a bumpy and wet boat ride. When we arrived at the reef we could see that there was more wave action on top of the pinnacles than in the deeper water surrounding them. Deon dropped a shot on one of the two pinnacles that comprise the reef (the top of the pinnacle we dropped onto is at about 18 metres, with the sand at about 30 metres). A murky descent (standard for False Bay in summer!) down the shot line led us to the top of the pinnacle, where visibility was only about 2 metres and it was very green.

As we ventured slightly deeper we encountered some invigorating (ahem!) thermoclines (one of them was actually visible as a haze in the water) and improved visibility. There was quite a strong current in places, and lots of surge.

There are many similarities between the reefs we dive on the western side of False Bay, but the overall pattern of the sea life was subtly different. The fish seemed far less skittish than their compatriots to the west, and happily swam within a few tens of centimetres from my mask. Nudibranchs abound, and close inspection of the corals covering the rocks is well rewarded. There seemed to be fewer sea cucumbers, and feather stars were not quite as dominant as they are in some of the other parts of False Bay. The corals, sponges and sea fans are beautiful and very numerous.

The sand around the reef is very coarse and full of shells, and the reef itself abounds with cracks, gullies, small pointy pinnacles, and walls that can be traversed at a variety of depths. The gullies appear to be much beloved by west coast rock lobster, and shysharks were quite common too.

Puffadder shyshark and some lobster friends

This reef is not in a marine protected area (MPA) – none of the eastern False Bay dive sites are. Kate, who regularly dives both sides of the bay, says she can see a distinct difference in the number of fish that they see on “their” side of the bay compared to the western side. So even if I am quite cynical about the competence of the administration and will to police the MPAs, clearly they are having some effect!

Dive date: 11 March 2012

Air temperature: 29 degrees

Water temperature: 12 degrees

Maximum depth: 24.8 metres

Visibility: 2-10 metres

Dive duration: 38 minutes

Meet and greet

It’s been a while since I’ve anthropomorphised sea creatures in print… So here’s a collection of encounters to entertain you (and if you haven’t dived in the Cape, to show you who lives here)!

Urchin and gas flame nudibranch at Partridge Point

I realise that the urchin and the nudibranch (and indeed the two nudibranchs in the picture below) probably have nothing to say to one another. But something about nudibranchs – their apparent lack of a face, maybe? – makes it very easy to ascribe thoughts and emotions to them. They also are rarely seen moving – to me, even with their riotously bright colouring, they are a blank slate upon which I may imagine whatever feelings I wish.

The urchin, therefore, has offended the nudibranch. The black nudibranch is giving the silvertip some avuncular advice, since the silvertip is still wet behind the ears, so to speak.

Silvertip and black nudibranch at Partridge Point

Sponge crabs grip onto sea fans with their little claws, and are often so covered by their protective layer of sponge (much like vetkoek) that you have to look really carefully to see their claws, let alone any other physical features. These two, however, seem to be getting cosy.

Granted, sea stars are not shy to interact (or compete) when a tasty snack is at stake. In fact, we often see great piles of them – particularly in the presence (or vicinity of) mussels. They seem to have no sense of personal space whatsoever. This, to me, makes the following image very charming. There’s an element of shyness and reserve (what, you don’t see it?) in the awkward approach of these two spiny sea stars that is so often lacking in starfish interactions.

Sea stars on a collision course at Long Beach

With that bit of nonsense over, I encourage you to go out and meet and greet someone today, even a stranger. Just not a creepy stranger, or that person at work whom you suspect is secretly stalking you and ascribes far too much significance to meaningless interactions.

Safety in numbers

There are many reasons why animals would gather together in groups. It may be for safety, like the moulting Japanese spider crabs in the Oceans DVD, it may be to find a mate and to socialise, or it may be because something tasty has fallen to the ocean floor and everyone wants in on the action.

Certain creatures, like sea cucumbers, rock lobsters, brittle stars and abalone, are always seen together. Sea stars, however, are usually quite solitary and seem absorbed in their own little world. A dive at Windmill or occasionally at Long Beach may sometimes reveal starfish engaged in huge pile-ons like over-excited school boys. Usually there are mussels involved!

Rock lobsters generally congregate in cracks and crevices in the rocky reefs they frequent. Unfortunately this habit of living in close proximity to one another makes them particularly vulnerable to over-exploitation by poachers (and by that I mean anyone who operates without a crayfishing permit, in violation of its terms and conditions, or outside official crayfishing season).

A gas flame nudibranch among strawberry sea anemones at Partridge Point

Strawberry anemones are gregarious, and live in colonies that cover patches of reefs and wrecks, right down to over 40 metres. Other creatures (such as the nudibranch above) often show little regard for their personal space, and walk right over these tiny pink creatures.

In both the picture above and the one below, you can see the dense congregation of sea cucumbers – more than one different kind – that covers many of the reefs in Cape Town. Even on sandy sea floors, such as around the Cape Matapan, golden sea cucmbers form fields of delicate tentacles protruding from the sand. In terms of biomass, sea cucumbers of all sorts are believed to be among the most prolific creatures in the ocean.

Urchins and sea cucumbers at Partridge Point

Newsletter: Whirlwind diving

Hi divers

Bernita in some nice visiblity at Oudekraal on Christmas day

The last week or so has been quite hectic with lots of diving being done. On Christmas day Clare and I (having discharged our family responsibilities the day before) did a lovely shore entry at Oudekraal in the company of Bernita. We had the entire ocean to ourselves and felt rather privileged.

Part of the Maori's varied cargo — Part of the Maori’s varied cargo

Gerard, Maurice, Keith, Angela, Tony and Clare in Hout Bay

Several of us enjoyed a pair of stunning boat dives in the Atlantic on Wednesday, and in between I’ve been shore diving and in the pool with Open Water students. Tomorrow I am starting a Rescue course and a Nitrox Specialty, as well as continuing with Open Water students. I also have Advanced students on the go so every day the weather permits, I am diving.

I won’t be on the boat this weekend, but Grant is launching and if you feel like a boat dive contact him directly (and fast). Conditions on the Atlantic side look quite good, but next week will most likely deteriorate somewhat with a large swell… Just in time for everyone to go back to work!

I wish all of you a safe long weekend and a peaceful and prosperous 2012. Hope to see you in the water soon!

regards

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

Diving is addictive!

Christmas wishes

To those of our readers (or, as I often suspect, to our lone reader – who may or may not be my mother) who celebrate Christmas, we wish you a very special day of rest and remembrance today. In celebration of the season, we have our own marine ingredients for the festive season.

We have a star…

… a Christmas tree…

Christmas tree (balancing atop an urchin shell)

… and a man in a red and white suit!

Wishing ALL of you good diving, safe travelling, and a gentle footprint on our environment in the year to come.

Tony & Clare

Sea life: Starfish at leisure

"Bring me a pina colada by the pool, please!"

I do not presume – not for one moment – to read the mind of a starfish, but these individuals seem to be living the good life. I think we can all be inspired by their capacity to relax into whatever situation they find themselves in. Most of these specimens were found at A Frame and Long Beach.

I have no idea what's going on here — I have no idea what’s going on here

Sea life: Yoga stars

I found these two spiny sea stars on a dive at Long Beach with Tony, Tami, Keren and Nils. For once they each have exactly five legs, but their postures are interesting. They appeared to be engaged in various physical jerks, and I thought I’d share. I just hope the starfish in the top picture isn’t accidentally ingesting his own legs.