Sea cucumbers

Dive sites: Vulcan Rock

Vulcan Rock is a dive site just outside Hout Bay. We dived it on a day when the south easter had been blowing for a while, so the visibility was quite good. The dive site is essentially a huge stack of granite boulders, with Vulcan Rock as the highest point. The rocks are covered with sea urchins, rock lobster, corals, sea cucumbers, brittle stars, and a bit of red seaweed.

Urchins, brittle stars, corals at Vulcan Rock

Esther and I stayed within the range of Open Water divers, not going deeper than 18 metres, but it is possible to go as deep as 30 metres at this site if you go for a bit of a swim. This is definitely a site to visit when the surface conditions are good and the swell is low (not that Hout Bay diving is ever great – or particularly safe – in a big swell).

I had the little Sony camera with me and took some happy snaps. Underneath all the granite is an enormous cave, with several entrances. Peet, who joined us on this dive, made a video of the cave that I will share with you later this week.

Dive date: 19 April 2015

Air temperature: 23 degrees

Water temperature: 10 degrees

Maximum depth: 15.6 metres

Visibility: 12 metres

Dive duration: 39 minutes

Sodwana diving photos (April 2014) – part II

Here are a few more underwater photos from our late April trip to Sodwana. Not great – see my disclaimer in yesterday’s post, for what it’s worth – but there you are.

Some of the sites we visited on Two Mile Reef were noticeably more barren – with less coral and more sand and rock – than others. I wonder whether this is a seasonal (or annual, or multi-year) variation, or whether it’s a slow process of the reef becoming silted up. Sites towards the middle of Two Mile, such as Garden Route, were covered with coral and looked exceptionally healthy.

Half the polyps on this coral have retracted

Otti and Matthijs (and Angie in the background)

Sodwana sees a lot of divers doing a lot of dives, year-round. There are at least eight dive charters operating from the beach, and Two Mile in particular sees some heavy traffic – including Open Water divers (many from Johannesburg) doing their first sea dives. During a recent conversation, Gerard blamed the heavy boat traffic for what he perceives as a slow decline in the health and biomass of the reef life in Sodwana; I wonder if the fishing activity that somehow co-exists with the dive charters has anything to do with it. Or perhaps we are imagining things, and just happened to dive on a few parts of the reef that were having a quiet day.

Sodwana is a Marine Protected Area, but perhaps it is not getting the monitoring and policing it requires to be fully effective. This is a widespread problem in all of South Africa’s MPAs, as well as a concerning lack of scientific thinking in the government ministries that are supposed to be keeping an eye on these things.

Whether we are imagining the changes in the reefs in Sodwana or not, it’s still a very beautiful place to dive, and worthy (as are all wild places on this earth) of our protection. You should go there and see for yourself!

Dive sites: Roman Rock

I’m not sure why I haven’t written about Roman Rock before. I’ve actually done four dives on the main reef, the first in 2010. The pictures in this post are from more than one of the dives – I’ll group them together, and you’ll be able to see by the water colour which dive is which.

Roman Rock reef is a very large collection of boulders separated by sand patches, centred on the Roman Rock lighthouse. Nearby reefs include Castor Rock, Livingstone Reef, Roman’s Rest, Wonder Reef, and Tivoli Pinnacles. The reef is comprised of granite boulders, heavily encrusted with typical Cape Town reef life – feather stars, brittle stars, nudibranchs, sea stars, urchins, sea cucumbers and ascidians – varying with the depth. If the current is strong you will find a lot of fish here, mostly roman and hottentot, enjoying the tasty bounty brought by the tide.

Feather stars and urchins jostling for space

Part of the dive is along high walls that are reminiscent of Atlantis Reef, further south. There are deep dead-end passages in between the rocks, wide enough to swim through (or drive a car through), and the rippled sand looks like a white carpet or a runway. In the middle of nowhere you will come across a ladder; it’s been there since the first time I dived Roman Rock in 2010. Your guess is as good as mine.

The site is suitable for Open Water divers, as the maximum depth one can attain while staying adjacent to the reef is about 18 metres. There are several pinnacles and shallower plateaus that are suitable for deeper safety stops. It goes without saying that each diver must have a surface marker buoy – the site is a relatively short boat ride from False Bay Yacht Club, but offshore nonetheless and there may be boat traffic, depending on where the current takes you.

Dive date: 3 August 2013

Air temperature: 22 degrees

Water temperature: 14 degrees

Maximum depth: 16.5 metres

Visibility: 10 metres

Dive duration: 38 minutes

Dive sites (Red Sea): Barge wreck (Bluff Point, Big Gubal Island)

There is a barge wreck at Bluff Point on Big Gubal Island in the Red sea, where we did an amazing, fast drift dive along the side of the lagoon. During that dive we did stop in briefly at the barge wreck (its origin and identity is unknown), but it was on a night dive the previous evening that we actually spent a significant amount of time exploring the barge.

It’s supposed to be one of the best night dive sites in the Red Sea, and we were amazed by the amount of life on and around the wreckage. We saw multiple large moray eels, huge basket stars, enormous urchins, and a crazy variety of other life. We jumped off the back of our liveaboard, swam under a neighbouring liveaboard, and found the barge wreck just off its starboard side. It was teeming with divers from our boat and the other liveaboard, but there was so much to see over such a spread out area that it didn’t matter too much.

My favourite thing was the basket stars, of which there were many. We saw some huge ones, with diameter nearly as big as my arm span, and some small, palm-sized ones. They are not the lovely blue-grey colour of the ones we see in Cape Town, but the intricate design of their many arms is the same.

We also saw a number of moray eels. Our dive guide told us that two big ones live on the barge wreck, named George and Georgina. The ones I saw and photographed were extremely large. As with the night dive we did at the Alternatives, the water was very still and very clear, so torch light actually shone an appreciable distance. This kind of night diving is so easy and wonderful that I think it might have spoiled me for night diving in Cape Town!

Dive date: 21 October 2013

Air temperature: 24 degrees

Water temperature: 26 degrees

Maximum depth: 11.2 metres

Visibility: 30 metres

Dive duration: 50 minutes

Dive sites: North Paw (Monty’s Pinnacles)

One of the pinnacles, rising to within 10 metres of the surface

It seems that it’s only on magnificent days that we end up launching from Oceana Power Boat Club. While my colleagues were having an end of year function just above Clifton Beach, I was floating on the surface a few hundred metres off the same beach, waiting to be picked up by the boat after a dive. You’ll recall that we had a week or more of incredibly strong southeasterly winds at the end of November. The wind dropped during the night of 30 November, and hours later we were on the boat. The aim was to complete Christo’s deep dive for his Advanced course, and our hope was for excellent visibility.

Christo & Tony at the safety stop, at the thermocline

The Atlantic is so capricious, however, that the surface layer was already turning green with a layer of happily multiplying phytoplankton when we arrived to dive it. I am unreasonably pleased with this picture of Christo and Tony at the safety stop, right at the boundary of the blue and green water.

Christo and Tony at Monty's Pinnacles — Christo and Tony at Monty’s Pinnacles

Swimming through a channel between boulders

Spectacular topography at Monty's Pinnacles — Spectacular topography at Monty’s Pinnacles

Beneath the layer of pale green we discovered crystal clear, freezing cold water. I can well understand how falling into the water in the Southern Ocean or Bering Sea can be fatal after this dive. Towards the end I doubted my ability to swim for the surface, and just wanted to lie down on the bottom and go to sleep!

Monty’s Pinnacles refers to part of the North Paw complex, a large area of granite reef that has several distinct dive sites within it. We have also dived the northern pinnacle. Monty’s Pinnacles lie a short distance to the north of the exposed rocks that mark the main North Paw reef. There’s a map here. The two pinnacles were discovered by local diving legend Monty Guest while scootering around the area in 2010. They rise to within 10 metres of the surface. The topography is spectacular, with great ridges in the granite that are so straight as to appear to be machine-hewed. Small stands of kelp grow all the way down to 25 metres, testifying to the clarity of the water here at certain times of the year.

Tony and some brittle stars on a boulder

I didn’t see much unusual macro life (perhaps in my near-hypothermic state I had reduced powers of observation), but the rocks are heavily encrusted with mussels, brittle stars, and urchins. There are very large west coast rock lobsters everywhere you look. I saw the odd sea cucumber and a couple of anemones, but the chief beauty of this site for me is the passages and tumbled boulders that one swims among. There are swim throughs here, but we didn’t find them.

The view upon surfacing is spectacular, with the Twelve Apostles and the Atlantic seaboard to feast your eyes on.

Dive date: 1 December 2012

Air temperature: 28 degrees

Water temperature: 9 degrees

Maximum depth: 25.9 metres

Visibility: 15 metres

Dive duration: 30 minutes

Violet spotted anemonesc — Violet spotted anemones

Mini pinnacle (not one of the official ones)

Article: New York Times & Nature on trawling

The New York Times recently published a short editorial on what commercial trawling is doing to the sea floor. Nature had published a similar article a month or so earlier, describing how the results of trawling were initially mistaken for the aftermath of an underwater landslide. You can see images of its effects here and here, and the Nature article has a close up photograph of trawled seabed.

If you’ve spent any time on the sand at one of Cape Town’s dive sites you’ll know that not only does the surface of the sand provide habitat for all sorts of creatures, but just under the surface live numerous others that may only venture out at night, or not at all. Imagine smoothing over that top layer, and dislodging the anemones, starfish, sea cucumbers, beaked sandfish, rays, worms, bivalves and their friends. Then imagine doing it again, within days, before any of the creatures could re-establish themselves.

In addition to removing all the fish from the ocean, our activities are apparently reshaping the ocean floor. That’s embarrassing, to say the least.

Read the NYT article here and the Nature one here.

Dive sites: 13th Apostle

Sea cucumbers covering parts of the reef

Positioned at the end of the Twelve Apostles mountain range (and thusly named), 13th Apostle reef is a distinct mass of granite boulders surrounded by a sandy bottom. Waves have long been observed to break here in bad weather, but the reef was only dived for the first time late in 2010. It’s quite a long (13.3km) boat ride from Hout Bay, near Llandudno.

We visited it on a day when surface conditions were somewhat choppy despite the lack of wind, and the boat ride there felt endless. And wet. Visibility, however, was stellar – when my buddy failed to arrive at the bottom I was forced to resurface, and on my way back down I could see Tony and Vanessa 15 metres below me. They, in turn, could see my legs and the boat while I was on the surface.

Tony & Vanessa, seen from near the surface

The top of the reef is between 6 and 10 metres deep, punctuated by deep cracks. There are in fact a couple of swimthroughs and overhangs, one of which forms a very large cavern. The reef itself has kelp growing on top and down to at least 15 metres which, as Peter Southwood points out, implies that light often penetrates to that depth, in turn implying frequent good visibility at the site. There is the usual covering of urchins, sea cucumbers, sea squirts, sponges, soft corals and hydroids.

Tony found me a beautiful basket star, and I discovered a brooding cushion star – an unusual sea star that makes me crave refined carbohydrates. We also saw large numbers of west coast rock lobster and schools of hottentot. Parts of the reef were covered by dense schools of baby fish – the Atlantic is very fecund.

This reef has a distinct edge, and while it’s quite large, if you land on it you probably won’t get lost. It feels quite far out to sea (it isn’t, really) and it’s essential (as with all Cape Town boat diving) to have an SMB to deploy before you surface. Tony in fact sent his up with me when I ascended early in the dive to look for my buddy. I descended on the line and found him and Vanessa at the bottom.

Dive date: 25 March 2012

Air temperature: 26 degrees

Water temperature: 10 degrees

Maximum depth: 25.8 metres

Visibility: 15 metres

Dive duration: 30 minutes

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

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

Dive sites: Caravan Reef

Caravan Reef is an infrequently-dived, simply enormous granite reef that lies very close to the slipway at Miller’s Point. Its northern reaches are close to the SAS Pietermaritzburg, but as can be seen from the map on its wikivoyage page the reef extends far south and has five distinct regions.

Peter Southwood swimming a shallow contour at Caravan Reef (south)

The one we dived (and the only one I’ve visited so far) is Caravan South, which is visible on the right of the map. The top of the reef is shallow, 4-5 metres, and after descending onto the pinnacle we dropped off the southern side. The southern side of the pinnacle, which runs almost west to east, is characterised by a vertical wall that drops down to about 20 metres on the sand. I love vertical reef structures – much easier to take pictures of something next to you rather than below you, but it does require some co-ordination and consideration among the divers to avoid getting in each other’s way.

The reef extending up towards the surface

The rocks at the south eastern edge of the reef

Narrow ridges of rock around the edge of the main reef

One of the sharp-edged slivers of rock beneath the reef

Another of the rocks at the base of the reef

Gullies on the eastern side of the reef extend to the sand

The reef is heavily overgrown with sea fans, bryzoans, corals and invertebrate life

Ascending towards the top of the pinnacle

The top of the pinnacle is overgrown with kelp

A gully leading back up to the top of the pinnacle

Goot and I (after a false start) swam east along the wall at about 15 metres depth, with the current, which was (to put it mildly) howling. At the corner of the reef is a mass of jumbled boulders with small overhangs. Some of these rocks have quite sharp edges, like ancient tree roots or massive parmesan shavings, so there is a lot of surface area for life to grow on relative to the volume of the rock.

A compass sea jelly battling the current around the reef

Compass sea jellies fighting the current

Goot inspects the root-mouthed sea jelly

A small jelly on the top of the pinnacle

Compass sea jellies and fish in the current at Caravan Reef

As we rounded the corner we encountered even more current – it was running roughly north to south, and coming around the reef, hence our difficulty with it whichever way we turned! Large numbers of compass sea jellies were being blown along by the current. We also saw an enormous root-mouthed sea jelly, with a small compass jelly caught in its tentacles (by accident – these creatures eat plankton). The false plum anemones living on the side of the reef were enjoying an unexpected bounty of jellyfish as some of the compass sea jellies had gotten caught on the side of the reef and were being devoured by opportunistic anemones.

False plum anemone slurps in a compass sea jelly

Strawberry sea anemones and sea cucumbers

A sunburst soft coral, with most of its polyps retracted

A false plum anemone lunches a compass sea jelly that got caught on the reef

Knobbly anemone with two urchin assistants

Red sea star cuddling up to a false plum anemone

The eastern edge of the reef has several cracks in it, mostly quite small, but we did see a few large roman taking advantage of the shelter. A small school of hottentot was surfing current on the eastern edge too, enjoying the snacks that it brought directly into their path. We swam into the current a short distance, became distracted by the root-mouthed jelly, and followed it back along the reef for a while. We then ascended to about 10 metres and drifted back down the reef with the current to the corner. By that stage we were getting low on air, so it was time to ascend to the top of the pinnacle. The surface current washed us off the pinnacle in short order, so we inflated an SMB and waited for the boat!

My favourite feature of the southern part of the reef is the vertical wall to the south, which extends along the eastern side as well to some degree. I’d like to explore the northern and western areas of this part of Caravan Reef, but the current prevented us from making much progress into those areas. Peter Southwood is busy mapping this reef, so contours should be added to the existing map on Wikitravel. I think that the current on the day we dived the reef had a lot to do with the extremely strong northwesterly wind that had been blowing for a day or two and dropped slightly on the day of our dive, but I’m not complaining – the visibility was stellar, almost top to bottom!