Sea life: Puffer fish

In Cape Town we find evil eye puffer fish, the gorgeously chubby creatures that have the ability to inflate their bodies when they feel threatened. Their flesh is deadly poisonous and they are considered a menace by anglers because of their bait-stealing tendencies.

Evil eye puffer fish buried in the sand
Evil eye puffer fish buried in the sand

They are often found buried in the sand – we found hundreds when we dived the North Battery pipeline – but sometimes you find them swimming about in the water column. They are ambush predators, hiding in the sand waiting for crabs and other small fish to eat. They don’t have teeth as such, but rather a sort of fused beak for biting.

Evil eye pufferfish on the sand at Long Beach
Evil eye pufferfish on the sand at Long Beach

They are not good swimmers at all, and are extremely docile when you swim over them or accidentally put your hand down next to them on the sand. They aren’t harmful to touch, but should under no circumstances be eaten.

Tiny puffer fish
Tiny puffer fish - can you see him eyeing you on the right of the photo?

I found this tiny, tiny chap at Long Beach – he was as big as the first joint of one of my fingers. He’s hard to spot in these two photos, but I promise he’s there! This is camouflage at its finest.

Spot the puffer fish
Spot the puffer fish - he's as big as a thumbnail!

We seem to see them in the greatest numbers when cold, cold water floods into False Bay – often after a strong north-west wind.

Bookshelf: The End of the Line

The End of the Line
The End of the Line

The End of the Line – Charles Clover

This book should be billed as compulsory reading for anyone who eats fish. Clover, a journalist, describes from various perspectives the effects of overfishing on the world’s oceans. The European Union comes in for a particular roasting, on several counts – which surprised me, because I thought it would be primarily the Japanese who get it in the nose for their exploitation of bluefin tuna.

As a mathematician, I am horrified by Clover’s indictment of the mathematical models used to manage fish populations. The more sophisticated these models have gotten, the less effective has our management of wild fish populations been. There is also (as usual) a disturbing disconnect between the mild-mannered scientists doing the work, and the public policy makers and governments who are chiefly interested in preserving their own status – of necessity a very short-term view of things.

That said, it is incredible how quickly wild fish populations have been decimated and even destroyed. Clover describes the piscine bounty that awaited the pilgrims arriving on the Mayflower in 1620, and describes how the same fishing grounds are now closed because there is simply nothing left to catch.

My favourite (and the most hopeful) part of the book was the section on marine reserves, and I was delighted and astonished to learn about Goat Island in New Zealand, about 90 kilometres north of Auckland. The reserve was established in 1975 and opened to the public in 1977 (it’s now a HUGE attraction for tourists and locals alike – refer to Sylvia Earle’s comments on the value of the whale watching industry as opposed to whaling for another example of how marine life can have more value alive than dead), and both Clover’s book and my internet wanderings confirm that the ocean there now teems with life to such an extent that children stand knee-deep in the water at the beach, surrounded by shoals of curious fish. Here’s Clover’s description of the place – I would LOVE to visit it!

Leigh is perhaps the world’s best example of what natural ecosystems look like when they are left alone, without fishing pressure, for a long time. The reserve has exceeded its founders’ original expectations, and not just from an ecological point of view. Before it was earmarked as a reserve, Goat Island was a popular fishing spot for fishermen. Conflict arose with the marine lab because, as Wilson put it, “people kept eating the experiments.” The reserve was created, after twelve years of lobbying by Ballantine and his colleagues at the university marine lab, for narrowly scientific reasons. Ballantine is the first to admit that he never foresaw what an attraction the reserve would become…

We stood looking at these unexpected beneficiaries of science. Most were families who had driven out of Auckland for the day to stand in the clear sea water and gawk as a profusion of fish swam around them. Others came to snorkel, renting a wetsuit on the beach for a few dollars, or to stare through the glass panel of the boat at the fearless shoals of large snapper, blue maomao, and spotties that swam above forests of kelp, only yards from the shore…

What happened to the ecosystem was also unexpected. Snapper are the most prized sporting fish on this coast – and for that reason increasingly small and scarce. In the 1,370 acres of the reserve, the largest snapper are eight times the size of the snapper outside. They are also fourteen times more numerous. Brochures tell you that you will also find butterfly perch, silver drummer, porae, red moki, leather jacket, blue cod, red cod, goat fish, hiwihiwi, butterfish, marble fish, red-banded perch, and demoiselles – all swimming around without fear of people and within a few yards of the shore. Indeed, they have so little fear that they may nibble you to see if you are edible.

Most of this marine menagerie is readily visible to an inexperienced eleven-year-old snorkeler in a rented wetsuit… Further out, in deeper water accessible to more adventurous divers, are delicate gorgonian fans, lace corals, sponges, sea squirts, and anemones. Under the kelp forests, hidden in holes and crevices in the rock ledges, are big rock lobster, or crayfish, much larger than those in the commercially fished waters outside…

This makes me kind of wistful when I think about what our coastline could look like, if the MPA permits were properly administered and the money collected went to actually protecting the ocean and deterring poachers. (Contact Underwater Africa if you want to stay up to date on this issue.)

In my post about sea urchins I mentioned how juvenile abalone shelter among urchins. When the rock lobster population gets out of hand, too many urchins (their favourite food) get eaten, and the population of abalone is affected. In the same way, the food chain has been severely disrupted in oceans around the world through the activities of humans. Furthermore, instead of restoring a balance by removing fishing from the equation in the worst affected areas, other top predators such as seals have been allowed to multiply unchecked. We aren’t allowed to catch undersized cod, but seals certainly are! Here’s Clover’s description of how the food chain is supposed to work, in the Goat Island reserve:

When the reserve was created, explains Ballantine, there was nothing particularly special about the marine ecology. The rocky coastal reefs were known as “rock barrens” because nothing grew on them. The most common bottom-living species were large sea urchins, which graze on kelp. As in other parts of New Zealand’s northeast coast, the kelp forests had virtually disappeared by the 1960s. The connection between the disappearance of the kelp and overfishing became clear only when the Goat Island Reserve had been established for many years. At a certain point,the undisturbed snapper and crayfish reached a size at which they could prey on the kina, or large sea urchins, that fed on kelp. So the kelp forests gradually returned, bringing in turn food and shelter for many other species of fish and shellfish. Biologists call this a “trophic cascade”, when the recovery of predators at the top of the food chain has effects that flow down to lower levels.

The book is written in a journalistic style, but it’s not always easy to keep track of the facts that Clover throws at one. He adds a bit of local colour with interviews with fishermen and officials, but some maps would have gone a long way towards demonstrating the extent of the problem and educating those less knowledgeable about North American geography than… well, who DOES know about American geography? (I doubt many Americans do!)

I also felt that Clover could have made more of just how incredible the different fish are, as marvels of nature. He mentions that the bluefin tuna can accelerate faster than a Porsche, and for many of the deep-sea fish he lists the very advanced ages they can attain (some over 100 years), but there’s very little sense of wonder in his descriptions. As you will be when you read this book, I think he may have been overwhelmed by the numbers and lost track of the victims in all of this.

The magnitude of the problem seems completely insurmountable, and as an individual there seems little to be done. I would encourage you, however, to read this book and be sensible about the fish choices you make. It’s both a human health issue – when we run out of fish, our diets will be MUCH poorer for it – and a conservation issue. Get hold of a SASSI card. Keep your conscience clean when eating seafood! Perhaps that can be a new year’s resolution for all of us…

The book is available here. I’ll do a review of the documentary based upon it as soon as we get a chance to watch it!

Sea life: Seals

This post is dedicated to Kate, who has a deep and abiding love for seals, and can think of nothing better than cuddling up to one – underwater or on land. (Actually, not – Kate hates seals, and is convinced that behind their puppy-dog features lurks evil intent. Apparently a woman in Cornwall was dragged off her body board and drowned by a playful seal, and this has led to Kate’s profound mistrust of these creatures.)

Seals at the Waterfront
Seals at the Waterfront

A good place to see seals is in harbours – Kalk Bay, the V&A Waterfront and Hout Bay harbour have large (and I mean that in the sense of numerically and also in terms of waistline) seal populations, no doubt attracted by the presence of the fishermen. A busy day at the slipway at Miller’s Point always includes a seal or two, as the fishermen gut their catch while they wait in the queue. The fish guts thrown over the side of the boats are perfect seal snacks.

Seal in Kalk Bay harbour
Seal in Kalk Bay harbour

There are a couple of places in Cape Town where you can go to dive with seals (and be guaranteed multiple sightings). Both these locations are also suitable for snorkeling, as long as there isn’t too big a swell (you’ll be swimming around a large rock in both cases).

  • Partridge Point contains a seal colony close to the western shore of False Bay. If seals aren’t your cup of tea, the reef extends to the east with numerous exciting sites such as Deep Partridge and Peter’s Pinnacles.
  • Duiker Island in Hout Bay also contains a seal colony, and is a short ride from Hout Bay slipway. The water is much colder than at Partridge Point, but the maximum depth is only about six metres which makes for fantastic light and photographic opportunities.
Seal at Miller's Point slipway
Seal at Miller's Point slipway

We’ve seen seals on many of our other dives. They’re frequent visitors at Long Beach and at the SS Clan Stuart, even on night dives (which can be a bit scary until you know what the dark shape tailing you is!). They like to hang upside down in front of divers, sometimes barking underwater (big teeth!) and often biting on bubbles. It’s lovely (yes, Kate) to have a friendly seal swimming next to you and checking you out with his big liquid black eyes.

Seal in Kalk Bay harbour
Seal in Kalk Bay harbour

On the surface, seals often lie with one flipper sticking out of the water. This is for temperature regulation – like whales, they’re well padded with blubber (this is why sharks like to eat them), but on their tails and flippers the veins are much closer to the surface. It’s a bit like sticking your leg out of the duvet at night to cool down, though I suspect for seals it’s often to warm up.


Happy and playful seals also give us a great deal of comfort as divers, because it means there are no sharks in the vicinity. The absence of seals does not necessarily mean there ARE sharks around, but if you were at one of the seal colonies and not a single seal joined you in the water, or if they were all crawling along the bottom, I’d be a bit worried!


Article: The Urban Times – Artificial Reefs

A mash-up of my post on artificial reefs, and Tony’s post on the one we created at Long Beach has appeared in The Urban Times. Check it out here.

Artificial Reefs in The Urban Times
Artificial Reefs in The Urban Times

Directions to Miller’s Point launch site

Boat dives in Cape Town are either done from Miller’s Point, Hout Bay, or (less frequently) Oceana Power Boat Club near the Waterfront. Tony is often asked for directions to Miller’s Point, and I am the one who has to write them (being the native Capetonian!). Here they are for future reference: (Launch fee is currently R80.00. June 2013)

Coming along the Main Road:

  1. This is easy. Keep on the Main Road through all the coastal suburbs – Muizenberg, St James, Kalk Bay, Fish Hoek.
  2. At the circle at the top of Fish Hoek Main Road, keep left and stay next to the sea. You are basically following the railway line along the coast.
  3. Carry on through Glencairn, and into Simon’s Town.
  4. Drive through Simon’s Town, past the golf course on your left, and the turnoff to Boulder’s Beach.
  5. Continue for several kilometres until you see a sign for the Black Marlin seafood restaurant and Miller’s Point caravan park on your left (in the middle of nowhere – no houses or anything).
  6. Now keep your eyes open – the Miller’s Point turnoff is the next one on your left, around a courner and over a small hill. Drive in and into the lower parking area (not the one immediately on your right as you enter, but in front of you to the right). The boats park in the upper parking area so don’t go in there.

Coming on the M3 highway:

  1. When you get to the end of the M3, turn right at the traffic light and contine through one more set of lights (Virgin Active on your right).
  2. Just before the next set of lights take the slipway to the left, up onto Ou Kaapse Weg. This turnoff is not well signposted!
  3. Now you basically stay on the same road until it ends abruptly in the ocean. Go over Ou Kaapse Weg into Sun Valley.
  4. Continue straight through two sets of traffic lights (stopping if they’re red), onto the Glencairn Expressway (Blackhill Road). This takes you over a small mountain into Glencairn.
  5. When you get to the sea, with a Spar on your left and a wetland on your right, turn right. Now you are on the Main Road.
  6. Directions continue as from Item 3 in the Main Road section above!

Here’s an aerial view of the launch site. The slipway is at the end of the T-shaped piece of road towards the top of the promontory.


You can zoom out on this map to see where Miller’s Point launch site sits relative to everything else. If you continue along the M4 (Main Road) past Miller’s Point, you will eventually get to Cape Point.

Things to be aware of

  • Miller’s Point is part of the stamping ground of a large troupe of baboons. They are hilarious to watch, but (especially if you’re a woman) the large males can be a bit intimidating. Keep your car locked, windows closed and sunroof securely shut in order to prevent them from raiding the vehicle for food – they know how to open almost anything, and will get into the car with you if they see the opportunity. DO NOT feed them.
  • Sometimes there’s a guard at the boom who wants an entry fee (I think it goes to the government). It’s less than R10 but make sure you have some small change on you.
  • There are no ATMs, shops or any other signs of civilisation at Miller’s Point. There are public toilets near the slipway, but their condition is wildly variable and you should take it as a given that there are no seats or loo paper.
  • Lately some of the boat skippers have been launching from the slipway at Cape Boat and Ski Boat Club, which is on the right hand side as you enter Miller’s Point. Be sure to check which slipway you’re launching from, as it’ll affect which parking area you’ll be meeting the dive boat in.

Bookshelf: The World is Blue

The World Is Blue: How Our Fate and the Ocean’s Are One – Sylvia Earle

The World is Blue
The World is Blue - Sylvia Earle

Sylvia Earle is a legend (I’ve said so before), and this is a book that flowed out of a TED talk she gave about the need to take urgent action on ocean conservation. I gained a huge amount of understanding about why indiscriminate fishing is a problem for ecosystems (she compares it to removing bits from a computer that look useless, and then expecting it to work afterwards). She also explains the extent of our dependency on the ocean – for example, one kind of plankton provides about 20% of the oxygen we breathe, with other kinds making up a further 50%.

Earle has a long history of ocean exploration, and has been scuba diving and driving submersibles since the 1950s. Her anecdotes about things she has seen and people she has spoken to are fascinating. She was part of the very early days of ocean exploration and recreational scuba diving, and has spent thousands of hours underwater (for comparison, I think I’ve spent only 40 hours breathing compressed air!).

Earle is a strong advocate for Marine Protected Areas – proper ones, that don’t allow fishing. She likens a MPA that allows fishing to a game park – say Kruger – that allows hunting! She also supports the initiatives such as SASSI that classify fish species according to the sustainability of the catch process and their level of endangerment. (If you don’t have a SASSI card, you need to get one before your next seafood dinner!)

I was particularly struck by Earle’s account of her response to a question asked of her in the 1990s by the head of the Japanese delegation at the International Whaling Commission: “… What’s the difference between eating a steak from a cow and eating whale meat?”

I tried to respond seriously: Cows are herbivores and go to market in a year or two, have been cultivated by people for food for ages, and require care and an investment of some sort by farmers; while whales are free, wild beings that belong to no one, are typically taken after they have lived for decades, and are relatively few in numbers (or are not “restocked” like cows), leaving an irreversible tear in the ocean’s fabric of life when removed. There are billions of cows, but all whale species are greatly reduced in number, some bordering on extinction owing to whaling. Taking even a few increases the risk of depletion owing to other pressures – storms, disesase, pollution, and fluctuating food sources. The whales of today have ancestral roots 65 million years deep, and nothing in their survival strategies factored in the impact of humans as predators. What might we learn from them as living creatures, able to communicate with sound over long distances, develop close-knit societies, navigate over thousands of miles with no maps, and perform daily deep-diving feats that defy the capacity of even the most athletic humans? If only considering whales as  a priceless source of knowledge, we discover that their value alive far exceeds their worth as pounds of meat. In narrowly-defined economic terms, the growing business of whale-watching is lucrative and demonstrably sustainable, while commercial whaling is subsidised, with a consistent record of “management” failure.

The World is Blue, Sylvia A. Earle, National Geographic Press 2009, pp 38-39.

Buy the book here if you’re in South Africa, otherwise click here. If you want to read it on your Kindle, go here. I highly recommend it.

Fish identification and conservation

Here are some useful web resources on identifying and conserving fish and marine life…

South Africa

Southern Underwater Research Group (SURG) – if you send them a picture of the creature you can’t identify, they will help! They have also published several books on identification of marine species.

The South African Saltwater and Offshore Fish Species List has a list of species, with information about some of them.


Census of Marine Life – this project occasionally makes the news with the discovery of new species.

FishBase – incredibly comprehensive database search of fish species.

World Register of Marine Species (WORMS) aims to be the most authoritative list of marine species’ names ever published.

Project GloBAL assesses the impact of fisheries’ bycatch on populations of long-lived marine species such as turtles, seabirds and ocean mammals such as dolphins.

The International Whaling Commission attempts to provide for the proper conservation of whale stocks.

The Southwest Fisheries Science Center has a list of the species they monitor, plus good information, on their Species page.

Bookshelf: A Guide to the Common Sea Fishes of Southern Africa

A Guide to the Common Sea Fishes of Southern Africa – Rudy van der Elst

A Guide to the Common Sea Fishes of Southern Africa
A Guide to the Common Sea Fishes of Southern Africa - Rudy van der Elst

Once I got over my initial shock of discovering that the pictures corresponding to each type of  fish were photographs of dead fish out of water, I found this book very useful. It’s no good for identifying fish as a scuba diver – unless you’re a very special (and illegal) scuba diver, you won’t be going through a pile of dead fish on land after a dive to find out what you saw! The fish don’t look anything like they do when they’re swimming about – the colours are all wrong, they’re limp, and their body shapes lose integrity out of the water. It was actually quite upsetting to me at first! The book is aimed at anglers, I think, and they’re a different breed to scuba divers.

What the book is very useful for are its detailed descriptions of the habitats of the fish (no doubt for anglers to hunt them down), their feeding preferences, reproductive behaviour, and very nice distribution maps. For the aquarists, there are even tips on keeping the fish in a tank, if that’s possible. It’s an excellent supplement to your knowledge of marine fish but should be used in conjunction with Two Oceans or A Field Guide to the Marine Animals of the Cape Peninsula as your first port of call for identifying the fish you’ve just seen.

The book can be purchased here if you’re in South Africa, otherwise click here.

Bookshelf: Conservation books

It’s our duty to educate ourselves on the threats facing the world’s oceans and ocean inhabitants. This reading list contains classics, coffee table books, and more modern works on climate change, overfishing, and more.

Concerning overfishing and climate change:

The magnificent Sylvia Earle, and her imitators:

The inimitable Carl Safina:

The inspirational Rachel Carson:

Classic nature writing:

High-level overviews:

Region specific:

Being a good citizen:

Documentaries: By subject

Here’s a summary of the documentaries we’ve posted about, categorised loosely by subject.


Nature’s Great Events
South Pacific
The Blue Planet
Wreck Detectives


The End of the Line
March of the Penguins
Saving the Ocean

Discovery Channel

Underwater Universe

National Geographic

Blue Holes – Diving the Labyrinth

Reality shows

Deadliest Catch, Season 1
Deadliest Catch, Season 2
Deadliest Catch, Season 3
Deadliest Catch, Season 4
Deadliest Catch, Season 5
Deadliest Catch, Season 6
Deadliest Catch, Season 7
Deadliest Catch, Season 8
Deadliest Catch, Season 9
Deadliest Catch, Season 10

Deadliest Catch – Tuna Wranglers
Deadliest Catch – Lobster Wars

Trawlermen, Season 1

Whale Wars, Season 1
Whale Wars, Season 2
Whale Wars, Season 3
Whale Wars, Season 4


Air Jaws
Blue Water White Death
Shark Week featuring Mythbusters – Jaws Special
Shark Men, Season 1
Shark Men, Season 2
Shark Men, Season 3


Wreck Detectives
Treasure Quest
Treasure Quest – HMS Victory Special
Ghosts of the Abyss