Biscuit skate on a night dive

We came across this small biscuit skate (Raja straeleni) while doing a night dive at the jetty in Simon’s Town, on the occasion of Diversnight 2017. They are found in the eastern Atlantic ocean all the way down to 700 metres depth, grow really slowly, and are frequent bycatch from hake trawling operations off the South African coastline. SASSI says don’t buy it. The species is data deficient on the IUCN Red List.

These skates have thorn-like stings along part of their tails, and this one seems to have a whole lot else going on in the tail region which looks as though it would help him camouflage among seaweed. (None of the biscuit skates pictured in our fish identification books have quite such fancy tail-gear.) Also watch how he flicks sand over himself for additional disguise when he stops moving.

Also, they can jump – perhaps a little known talent… Once, while Clare was on duty at the aquarium, a small one leaped right out of the shallow ray pool that used to be next to the touch pool, and landed on the floor. It was a quiet Sunday afternoon. A quick manhandle and he was replaced in his pool (and that exhibit was moved soon after)!

Coastal foraging part II: the feast

The various edible seaweeds that we foraged
The various edible seaweeds that we foraged

After foraging on the sea shore for edible seaweeds and mussels under the guidance of Roushanna and Gael from Good Hope Gardens, we returned to Gael’s house in Scarborough to prepare a meal with our finds. The group divided into four, and we worked together to prepare the food using recipes provided by Roushanna.

Decorating the sushi rolls
Decorating the sushi rolls

Sushi rice mixed with finely chopped sea lettuce (Ulva spp) formed the base of vegetarian sushi rolls, which were decorated with kelp, tongue weed, radishes, avocado, mayonnaise, and a secret sauce (recipe for the rolls here). Sea lettuce was also the seaweed of choice for a couscous and rocket salad, decorated with hibiscus flowers and miniature tomatoes (recipe for the salad here).

I worked on the coleslaw, made from finely sliced red cabbage, carrots, and hanging wrack (Brassicophycus brassicaeformis) – a seaweed I found so tasty and crunchy I could have sat right there in a rock pool and eaten it directly off the rocks. The mussels were picked over, scrubbed, and prepared with white wine, cream, onion, and garlic. Crusty ciabatta soaked up the sauce. Once we were done, it looked as though we had enough mussel shells for our own personal shell midden!

Rinsing and scrubbing the mussels
Rinsing and scrubbing the mussels

Roushanna prepared nori (purple laver, Porphyra capensis) crips for us (like kale chips, but with a crispier texture and more flavour), and chocolate nori ice cream for dessert. We supplied our own drinks. During breaks in the lunch preparation some of the group enjoyed a face (and hand) mask made from seaweed ingredients. Others of Roushanna’s recipes you can explore for yourself are for sea biscuits (scones made with sea lettuce), fruity vegan jelly, and kelp and avo salad.

Lunch was a collaboration, and a tasty culinary adventure. I found it marvelous to discover what is available on the sea shore, and to get a small hint of how our strandloper ancestors foraged on the Cape Peninsula.

Preparing our foraged lunch
Preparing our foraged lunch

(Puzzled what this is all about? Read my first post about coastal foraging here.)

Coastal foraging part I: the forage

Roushanna educates us about foraging for seaweed
Roushanna educates us about foraging for seaweed

A chance conversation with a friend who also volunteers at the Two Oceans Aquarium led to me enrolling in a coastal foraging course with Roushanna and Gael Gray from Good Hope Gardens, the nursery between Scarborough and Cape Point. Their coastal foraging courses are run during the summer months (I went in December), on dates close to spring tide, so that the maximum possible area of shoreline is available to forage on. The course takes the form of a rock pool expedition on Scarborough beach, followed by lunch – prepared by the participants – at Gael’s beach cottage.

Foraging for edible seaweed
Foraging for edible seaweed

As I get older I am finding it increasingly difficult to suppress a wildly eccentric streak that frequently finds me – consciously or unconsciously – making small preparations for some kind of apocalypse (zombie or otherwise). This might be related to living on the South African roller coaster for too long, but whatever the origin of this latent anxiety, it has served to make our home life more sustainable and – little bit by little bit – more independent of the electricity grid, the municipal water system, and grocery stores. The idea of coastal foraging dovetails nicely with my desire to learn how to live a little bit more off the land than off the shelves at Woolworths!

Mollusk permit inspection by fisheries officials
Mollusk permit inspection by fisheries officials

It is important to respect some simple rules to ensure that your foraging is sustainable, safe, kind to the environment, and legal. Each of us had purchased a mollusk permit allowing us to harvest mussels, obtainable from the post office (available for R94 using the same form as the scuba diving in marine protected areas permit), and these were inspected by fisheries officials quite early on in our forage. You don’t need a permit to harvest seaweed (however if you wanted to do it on an industrial scale you might need to go through official channels).

There are three types of mussels found on South Africa shores: the ribbed mussel and black mussel are indigenous, and the Mediterranean mussel is introduced. Unfortunately Mediterranean mussels out-compete the indigenous varieties, and we only saw one or two black mussels while we were out. The mussels we harvested were the Mediterranean variety, distinguishable from black mussels by the thick, flat edge to their shells. Black mussels have pointy edges all around their shells, making them more streamlined.

Mediterranean mussel (left) and black mussel (right)
Mediterranean mussel (left) and black mussel (right)

There is only one type of seaweed growing along our coast that is harmful to eat (acid weed – Desmarestia firma, which has sulphuric acid in its fronds). This brown algae species does not grow on the rocky shore but only further out in the surf zone. This gives rise to the simple rule of only harvesting seaweed that is growing on the rocks, and never collecting seaweed that is floating free.

When harvesting seaweed, we used a pair of scissors to avoid pulling the entire plant off the rocks, and cut no more than a third of the leaves. Seaweed is full of vitamins and minerals, particularly iodine and potassium. It isn’t something you’d make a whole meal of, but it is a healthful addition to many dishes and – once you know how to prepare it – tastes pretty good!

Clouds at Scarborough
Clouds at Scarborough

You can read more about the Good Hope Gardens coastal foraging experience here and here. Watch this space for more about what we prepared with our seaweed spoils…

Abalone farm tour in Hermanus

Abagold abalone farm in Hermanus
Abagold abalone farm in Hermanus

Abalone (or perlemoen, Haliotis midae) is a highly exploited marine resource in South Africa, to the extent that it is currently illegal for individuals to harvest abalone from the ocean. All fishing was suspended in early 2008. Formerly it was possible to get a permit to do so. Limited commercial fishing has been allowed since 2010.  The government acknowledged that this would cause further depletion of the wild stock of abalone, but framed the decision as one to protect the livelihood of approximately 1,000 abalone fishermen. When there is no abalone left to fish, I wonder what those fishermen will do?

Ten, twenty and forty year old abalone
Ten, twenty and forty year old abalone

The demand for this unprepossessing grey mollusc is almost limitless, primarily from the east, where it is viewed as a status symbol and is highly sought after at banquets and to prove the host’s prestige. Given the huge demand and the fact that South African waters are the natural habitat of this species, abalone farming has flourished in South Africa, with eleven farms in operation. The largest is Abagold, with four farms located in Hermanus. Abagold employs over 350 local people (it is the largest employer after the municipality). Farm tours are offered every week day at 11am (they cost R50), and Tony and I did one on our way back from De Kelders.

The Abagold farming operation is extensive, actually consisting of several separate farms all located close to the (new) harbour in Hermanus. The tanks are supplied with fresh water directly out of the ocean – the temperature (generally 15-18 degrees) and water quality is not adjusted at all, since this is the optimum natural habitat for the creatures. The animals are fed on kelp, sea lettuce, and specially manufactured abfeed, and no chemicals are added to the water. As a result, the farm can pump the water straight back out into the ocean without causing any contamination. There is a constant circulation of millions of litres of water through the farm, keeping the abalone oxygenated.

The holding pens have a beautiful sea view
The holding pens have a beautiful sea view

Breeding stock are kept separately, and range in age from three to 30 years. Pairs are retrieved from the ocean periodically, and returned after a time. Abalone are distinctively male or female, distinguishable by the colour of their gonads, which are nestled under their shell above their large fleshy foot. Abalone spawn between August and November in nature, prompted by increased oxygen levels in the water. To stimulate spawning in captivity, hydrogen peroxide (H2O2) is added to the water containing broodstock, which causes their muscles to contract and release eggs and sperm.

Three to six month old abalone
Three to six month old abalone

Eggs and sperm are mixed in the correct proportions, and fertilised eggs sink to the bottom of the tanks where they are sucked out and placed in tanks where they hatch after several hours. Algae is specially cultivated on large plastic sheets, to which the free swimming larvae attach when they are ready (after about a week). They spend about three months feeding on these algae-covered sheets of plastic. The baby abalone (spat) are beautiful, with blue and turquoise, perfectly formed little shells 3-5 millimetres in size.

In order to remove the fragile abalone from the plastic sheets, they are anaesthetised with an infusion of magnesium sulphate into their water, which enables them to be gently rubbed off the sheets. It is around the age of three months that they develop light-sensitive eyes, which prompts them to seek out darker hiding places. Black plastic cones are supplied under which the young abalone live for another three to four months.

The blue-grey colour of the gonads visible here shows this is a female
The blue-grey colour of the gonads visible here shows this is a female

At about six months of age the abalone are sorted by size and moved into simple tanks with fittings that are constructed largely of standard irrigation piping and hard plastic sheets. The abalone are quite sensitive to their environment and water has to be kept very clean. They spent the next 3-5 years growing in their tanks.

Kelp is collected to feed the abalone at various farms in the Hermanus area
Kelp is collected to feed the abalone at various farms in the Hermanus area

When the abalone are large enough (about 250 grams, I think – a bit bigger than my palm), they are removed from their shells. The gonads, mouth, eyes and other organs are discarded, and the foot is either canned in fresh water and pressure cooked in the tin, or dried, in about a 50-50 split. All the production is exported to Hong Kong, China, Malaysia, and Singapore, with a 440 gram tin of abalone in brine fetching R200 to R450 for Abagold (it obviously costs more to buy it in the shops). The farm produces nearly 500 tons of abalone per year. This is big, big business.

We were very excited to see how sustainable this aquaculture model is. Fish farming isn’t a wonderfully clean or sustainable business, but this seems to be an effective way to reduce demand for wild abalone without harming the environment. There is a long way to go, however, before supply of abalone outstrips (or even comes close to matching) demand – according to our tour guide, there are buyers for whatever quantity of abalone the farms can produce. Legally harvested and farmed abalone comprised one ton out of the seven tons of abalone that left South African shores last year. The scale of the poaching problem is massive.

Sea life: Hermit crabs

Hermit crab in an old helmet shell
Hermit crab in an old helmet shell

I’ve been holding off on this post chiefly because hermit crabs are devilishly difficult to photograph. They look really cool, beetling around on the sand, but getting the camera to an angle that captures their little hairy legs and beady eyes is tricky. Plus, at the first hint of interference, they disappear into their shells.

Large hermit crab at Long Beach
Large hermit crab at Long Beach

Most of our local dive sites are overrun with hermit crabs. I mean it – I spend a fair amount of time lying on the sand waiting for Tony to finish skills with his students, and these little guys are ubiquitous.

Hermit crab on shell patch
Hermit crab on shell patch

There are patches of shells at Long Beach that look kind of deserted, but if you watch for a while you can see ten or twenty hermit crabs crawling over each other. I wonder whether this isn’t the equivalent of a used car lot for them: hermit crabs use empty shells from other molluscs as their homes. When they outgrow the shell, they must find a new one, and quick as a flash crawl out of the old shell and into the new. There is a high degree of competition for good shells. More than once we’ve seen two of these little guys tussling over real estate.

When out of their shells, these little crabs apparently look more like lobsters, with a soft tail part (hence the need for a shell). We get a couple of different kinds in the Cape, but most of them have pink hairy legs and bad attitude. They are hugely entertaining if you just lie and watch them, but as soon as you pick them up they retreat into their shells (justifiably so) and wait to be released.

Overbalancing - shell too large?
Overbalancing - shell too large?

As the crabs grow, they must find larger and larger shells as homes. The competition is fierce. Sometimes we see absolutely huge, venerable granddaddies like the one below, with a forest of sea lettuce on his shell.

Hermit crab with decorations
Hermit crab with decorations

We see them on day as well as night dives, and they seem to be quite active at night. Here’s one I found in the shallows one evneing at Long Beach.

Hermit crab at night
Hermit crab at night

They can be quite fierce – every evening the starfish are removed from the Touch Pool at the Two Oceans Aquarium because otherwise, while unsupervised, the hermit crabs nip on their limbs.

Update on the artificial reef: 4 months

The artificial reef, covered in sea lettuce
The artificial reef, covered in sea lettuce

Tony and I installed a small artificial reef on the sand at Long Beach on 20 November last year. We checked on it after 10 days, and again after nearly 4 weeks, and then did not visit it for an extended period of three months during which the visibility was very bad. Summer diving in False Bay is an exercise in patience!

This used to be a cream Woolworths plant pot
This used to be a cream Woolworths plant pot

We visited it again recently, but my camera battery had given out after too much diving and photography for one little camera for one day. We returned to the artificial reef on Saturday 19 March, after it had spent 119 days in the water (4 months).

Algae-encrusted PVC pipe disappearing into the sand
Algae-encrusted PVC pipe disappearing into the sand

The reef itself is now so covered with sea lettuce that we almost swam right past it. The PVC pipes are almost completely buried in the sand, and algae encrusts almost every surface except for the cable ties. Feather stars seem to have taken a particular liking to the sponges, which have retained their shape (if not their colour) remarkably well.

Sign (left) and sponges (right) covered with feather stars, ascidians and hermit crabs
Sign (left) and sponges (right) covered with feather stars, ascidians and hermit crabs

The reef is populated by lots of (shy) klipfish, many of whom take cover in the sea lettuce. One, however, was very friendly and I almost got left behind playing with him on the sand.

Friendly klipfish
Friendly klipfish
Klipfish and warty pleurobranch
Klipfish and warty pleurobranch

We found a very fat pipefish, and a whole bed of hermit crabs going about their business. At least one warty pleurobranch was in residence, sitting on the wooden box.

Fat pipefish on the reef
Fat pipefish on the reef
Mask box covered with algae
Mask box covered with algae

The sign requesting divers not to mess with the reef is completely encrusted with sea squirts of various sizes and descriptions – larger ones as well as the smaller colonical ascidians. It’s not legible any more!

Sign overgrown with ascidians
Sign overgrown with ascidians

We were amazed by how thoroughly the sea has taken over the various items we laid down four months ago. What was originally quite an ugly collection of pipes and other random objects has become a thriving little oasis on the sand. We purposely placed the artificial reef away from other rocky outcrops or detritus that housed copious marine life – out on the sand, we’d be able to see who passed by, and know that the reef was seeded from scratch and not from an adjacent underwater feature.

For a before and after comparison, I’d recommend you go and check out what the reef looked like in these prior posts:

Sea life: Sea lettuce

Tony and Mark walk down Long Beach
Tony and Mark walk down Long Beach

I really, really hate sea lettuce. It does this (see above) to the beach after rough sea conditions, and (see below) it’s really, really annoying on a dive.

Tony behind some sea lettuce
Tony behind some sea lettuce

The only good thing about sea lettuce is that it provides camouflage for super klipfish, like this friendly one I met on a dive last year at Long Beach. Their green colour often perfectly matches the colour of the sea lettuce.

Super klipfish in the sea lettuce likes to be tickled
Super klipfish in the sea lettuce likes to be tickled

There seems to be a sudden growth spurt of sea lettuce around the middle of spring, and for a few months all our favourite False Bay shore entries are littered with it. It gets wrapped around your hoses, caught in your BCD, tickles your cheeks in a most creepy manner, and (most annoyingly) makes photography a frustrating challenge as it waves about everywhere!

Sea lettuce on the kinked anchor chain at Long Beach
Sea lettuce on the kinked anchor chain at Long Beach

Sea lettuce is eaten by sea hares and other sea slugs, as well as some marine mammals. It’s also extensively eaten by humans, in salads, soups and stir fries. I wish they’d eat more of it.

Sea lettuce attached to the end of a kelp stem
Sea lettuce attached to the end of a kelp stem

Sea lettuce seems to grow on anything and anywhere. We’ve seen a lot of it attached to kelp stipes, taking advantage of the extra height to get some sunlight from closer to the surface. The leaves are incredibly delicate – sometimes only a single cell thick. This doesn’t make me feel sorry for it, though.

Sea lettuce on the wooden wreck at Long Beach
Sea lettuce on the wooden wreck at Long Beach

If you need any more evidence that sea lettuce is bad news, read this BBC news article. It is believed to have been directly responsible for two deaths in France. I think it’s even more malevolent than seals are!

Opportunistic sea lettuce hitching a ride to the surface sunlight on a kelp plant
Opportunistic sea lettuce hitching a ride to the surface sunlight on a kelp plant

Sea lettuce is a frustration to divers, and some people find it genuinely scary. It can be quite a vertiginous experience to swim over a patch of sea lettuce that moves beneath you. I think Corne enjoys sea lettuce, however, but for reasons that the following photo make clear – it releases his inner child!

Corne playing with sea lettuce
Corne playing with sea lettuce

Here’s what happens when sea lettuce dies… All the brown marks on the sand in this picture are from dead sea lettuce that has decomposed and left its tasty organic stain all over the shallows. These marks will eventually disappear, but not before providing a lot of nutrients for the organisms in the vicinity. Now THAT is what sea lettuce is for!

Decomposing sea lettuce at Long Beach
Decomposing sea lettuce at Long Beach

Sea life: Sea star shapes

I’ve described (and illustrated) the remarkable ability of starfish to regrow limbs when they come a cropper. But sometimes we see starfish that are stubbornly resisting the five limbs trend… Either they haven’t started growing new legs, or they’re just in equilibrium with the number of limbs they have. Sometimes more than five!

One

We couldn’t decide if this guy – essentially just one leg – was alive. The leg appeared to be hanging onto some sea lettuce, and all the little tube feet were intact. I touched it, and it felt like part of a live starfish (I am intimately acquainted with the feel of starfish from my time at the Touch Pool). Good luck to him! I think he should be known as a linefish until he proves otherwise…

One leg!
One leg!

Two

Here’s our wedding starfish, who obligingly lay in a heart shape for us! Shannon, who made our invitations, transferred his portrait to her design in shades of blue. So he looked arty and unique, and, I thought, very beautiful.

Our wedding starfish at Long Beach
Our wedding starfish at Long Beach... see, he is lying in a heart shape!

Three

I found this three-legged sea star on the SS Cape Matapan opposite Cape Town Stadium. It was fitting, because Tami was my dive buddy!

T for Tami on the SS Cape Matapan
T for Tami on the SS Cape Matapan

Four

This guy who we found on a dive we did on the Romelia doesn’t seem to need his fifth leg – he’s showing no signs of developing a new one and looks exceptionally healthy!

Four legs on the MV Romelia
Four legs on the MV Romelia

Five

For five legs – boooooring! – you can go here! (Or, here.)

Six

Finally, I leave you with a starfish for whom five legs just wasn’t enough. We occasionally see these specimens, where it seems that the “regrow leg” instruction got repeated too many times. This one was also on a dive we did on the Romelia. Count his legs carefully…

Count the legs... Carefully!
Count the legs... Carefully!

Friday poem: The World Below the Brine

You’d almost think that Mr Whitman was a diver himself…

The World Below the Brine – Walt Whitman

The world below the brine,
Forests at the bottom of the sea, the branches and leaves,
Sea-lettuce, vast lichens, strange flowers and seeds, the thick
tangle openings, and pink turf,
Different colors, pale gray and green, purple, white, and gold, the
play of light through the water,
Dumb swimmers there among the rocks, coral, gluten, grass, rushes,
and the aliment of the swimmers,
Sluggish existences grazing there suspended, or slowly crawling
close to the bottom,
The sperm-whale at the surface blowing air and spray, or disporting
with his flukes,
The leaden-eyed shark, the walrus, the turtle, the hairy
sea-leopard, and the sting-ray,
Passions there, wars, pursuits, tribes, sight in those ocean-depths,
breathing that thick-breathing air, as so many do,
The change thence to the sight here, and to the subtle air breathed
by beings like us who walk this sphere,
The change onward from ours to that of beings who walk other spheres.

Update on the artificial reef: 27 days

After deciding that an artificial reef would be a cool project to do at Long Beach, Clare, Kate and I installed the reef on 20 November 2010, and revisited it on 30 November. Clare and I visited it again on 17 December 2010 to see how things were progressing.

Starfish on the PVC piping
Starfish on the PVC piping

The starfish are still loving the PVC pipes and quite a few of them have moved in.

Barehead goby cosying up with a starfish
Barehead goby cosying up with a starfish

Many barehead gobies are in the area and hide under the piping and other features of the reef.

Klipfish living in the coffee jar
Klipfish living in the coffee jar

A small klipfish has moved into the coffee jar, which is getting quite covered with green algae and sea lettuce. He seems to feel quite safe in there and there’s lots of room for him to grow.

Feather star on a piece of wood
Feather star on a piece of wood

We even found a pipefish snuggled against one of the very green and grassy PVC pipes. Can you see him in the picture below?

PVC pipe with plant growth and a pipefish
PVC pipe with plant growth and a pipefish

Several hermit crabs have also made the artificial reef and its general area their home.

Barehead goby and hermit crab at a pipe junction
Barehead goby and hermit crab at a pipe junction