By Bob Halstead

“What’s that stink!”

I sniff again .. nausea .. nostalgia .. nausea. Nostalgia?

I have recognised the smell, and memories waft around of the days when every other diver was a fanatical shell collector, and our boat stank of the putrid rotting flesh of dead molluscs. It is not hard to track down the source, which turns out to be a buoyancy compensator pocket. The owner is interrogated, and the crew ordered to prepare for a keel hauling … but it turns out that the shell was collected on the previous dive an hour before, already dead, but with some decomposing flesh remaining out of sight. When the diver tells me that he had to pick it up, it is such a gem, I understand completely. The beauty of sea shells has held collectors in awe for centuries.

When scuba divers realised that they had easy access to these gems, shell collecting became a popular occupation underwater. But somehow the fact that there was a live animal inside the shell was just a nuisance. The animal detracted from the shell. The animal was ugly, and slimy and smelly and you were almost doing the shell a favour by liberating it from the monster that lived in it. The fact that this miserable creature had miraculously created the masterpiece of the shell was ignored, and shells were collected with the same fervour as if they had been emeralds or diamonds.

I caught the same fever, and my wife Dinah and I spent many hours underwater searching for these often elusive treasures. We learned that most shells become active at night and leave their daytime hiding places to graze and hunt after dark. So night diving became a regular part of our lives. Every discovery was a joy and we collected the shells just as if they were valuable jewels. Soon we were rich! However it did not take long for us to wonder what we were actually going to do with all these treasures, and when one of our guests came up from a dive with a dozen tiger cowries with the intention of keeping the lot we realised we had a serious problem.

Thinking of ourselves as concerned conservationists (1970′s style) we introduced some rules. No longer could our guests just collect whatever they felt like. Giant triton shells were banned completely when we learned that they are one of the few predators of the “Crown of Thorns” sea star. Then, for collecting live shells, we decreed:

1. Only one specimen of each species allowed, and only then if you do not already have it in your collection.

2. Only specimens in gem condition allowed. Poor specimens with chipped or scarred or encrusted surfaces were good for breeding but useless for a collection.

3. All specimens collected must be properly cleaned. (Many would be collectors when faced with the stench of dead shells decided to dump them rather than clean them for a collection)

4. Only collectors armed with collecting jars, and spirit to pickle the shells and reduce the stench, would be allowed to collect.

Some of these were hard for us to police and we just hoped that guests would appreciate our aims and comform. People being what they are this did not really work out well, but our consciences were appeased for a while and back we went to improve our collection.

By now we had representatives of all the common species and the collecting became far more interesting. Now it was more than browsing over the reef and looking under the odd piece of dead coral. Now it was more a case of planning a campaign to find that particular cowrie or this particular cone shell. We had to try to discover its habitat which meant we had to dive places we otherwise would never have dreamed of diving. River mouths, great; muddy bays with one meter visibility, wonderful; dead coral rubble, very productive. We coined the name “Muck” diving to describe these habitats. Then we found out that some shells live on other creatures and we started to spend hours staring at clumps of sea whips, and a single sea fan or tree coral.

This is what the nostalgia was for. It was a time of discovery for us, but the important thing that we discovered was incidental to the shells that we collected. We realised that we could now SEE underwater, and that is the most exciting discovery that we ever made. Perhaps I had better explain. Time after time we have guests surface from a dive and tell us “Nothing down there, reef must be dead, can we move on to another dive site?” or variations thereof. Often I’ll tell them to listen to what the others have to say and then I question returning divers. Almost inevitably one of them will plead for us to stay where we are as he or she has just found this or that incredible beast and wants to change film and return to get more photos of it. What the first diver really meant was that nothing larger than five foot swam directly in front of his face mask … he had not learned to see, and from my experience, even if animals larger than five feet had swum directly in front of the diver’s face mask he often still would miss them.

We do dive reefs that are so full of marine life that all any diver has to do is to find a comfortable perch, stay still and watch the show. But to get those different, special encounters with the more unusual critters, you sometimes have to dive reefs which to first appearances look remarkably dull. One reef in particular that we regularly visit I make an apology for before anyone even gets in the water. Even then we still get comments – “You really expect us to dive HERE? What is this!”. So I ask for trust. “I know it looks pathetic but just get in the water, swim to 30 feet and you will see these brilliant fire urchins. If you LOOK at the urchins you will discover shrimp, crabs and shells living on them. Then look at the crinoids because ghost pipe fish live in them, and do you realise that those dead coral rocks are the home of a family of octopus, and that five different species of lion fish live on that tiny reef, and over there is a pair of blue ribbon eels. Then, at night …”. Just as a clincher I sometimes add that one lucky couple looked up from the bottom to find a good size marlin circling them, right here! This is a real place, Lauadi Beach in Milne Bay, and it ends up often producing the diver’s favorite encounters and biggest raves. But if we had not learned to see we would never have discovered this site. No one would pick it for a dive site as, from the surface, it looks very dead. But since we were hunting for shells, we were actually avoiding the classic beautiful reefs, which are not nearly as productive as other environments. We found many shells but we also found an incredible array of other amazing animals. Anyone who had not developed an eye would have dismissed the site in a moment.

As our collection grew so our rate of discovery slowed until it became a rare occasion when we actually took a live shell. On the other hand, our experience of the more unusual tropical dive sites grew and so did our appreciation of what incredible animals molluscs are. We learned how they were adapted to diverse marine environments and that they lived in close harmony with many other types of marine creatures. As we started to think more in terms of the animal and less in terms of the shell, collecting became a less and less attractive proposition, so, instead of grabbing, I started to photograph the living shell in its environment and found that this is even more of a challenge.

Many shells love silt and mud and live in filthy water – conditions that are the worst for underwater photography. My diving skills had to be improved to such an extent that I could move close enough to the bottom to be able to see the shells but slowly and carefully enough that I did not stir up any sediment. I had to look as far ahead as visibility would allow to enable me to stop well before reaching the shell, otherwise my momentum would take me past the shell with no possibility of turning around without disturbing the bottom. I had to be careful not to disturb the shell or the animal would retreat into the shell and I was not interested it taking pictures of what would just look like a dead shell with a marine background. This meant that I had to avoid touching the shell and also avoid disturbing the sand or silt or whatever surrounding it. For this reason better pictures could be obtained with a reflex camera in a housing than with Nikonos and close up framers. Since some nocturnal shells are also very sensitive to light I developed a technique of tracking the shell in faint light at the edge of my torch beam, then getting a single shot before the animal could hide.

We have learned many of the tricks that shells use to camouflage themselves. The red smudge on the sunken log is not a small sponge but a murex shell with a layer of sponge growing on its surface. The lump on the side of a red sea whip is not a deformity but a spindle cowrie whose extended red mantle has false white polyps growing from it identical to the real polyps of the sea whip. The small mound at the end of a sand trail hides an auger or olive shell waiting for night before continuing its wanderings. To find the white “egg” cowrie Ovulum ovum you have to search for a black lump since the animal is black and its mantle completely covers the white shell. Beautiful wentletraps live in the sand surrounding sand anenomes that they feed on, very rarely emerging, and the delicate Rapa rapa lives entirely within the flesh of a soft coral.

Some of the shells are voracious predators. Who can forget the sight of a large baler shell, siphon high, hunting for other shells across the sand. These are fast movers well able to overtake slower moving molluscs which are then siezed and smothered in the animals enormous foot. One evening we pulled into a pretty bay to shelter from the trade winds. Sea grasses could be seen near the black sand beach, and some silty coral near the rocks at the entrance to the bay. The water looked clear and we decided to night dive. It turned out we had, by chance, found the habitat of one of the most exquisite of all shells, the Venus Comb murex, Murex pecten. This murex has long delicately curved spines radiating out from its shell like so many teeth of a comb. Or rather three combs since as the animal grows it increases the size of its shell with an extra 120 degree growth, and a new set of spines. Most collected specimens have been trawled from the bottom in fish nets and the spines damaged. We were admiring perfect specimens pushing their way straight up through the silt then wandering around the bottom. This was exciting stuff, but what we saw next was astonishing. Murexes feed by capturing other shells, boring a perfect hole throught the victims shell and sucking out the flesh. Our comb murexes were moving with their siphon, with all the spines either side, raised from the bottom. Then we saw why. One had found a small clam, it approached, manouvered the siphon above the clam then slamed it down and pulled down into the bottom, trapping the clam in a perfect cage.

Now we do not allow any collecting of live shells from Telita. Indeed it is now illegal for non-residents of Papua New Guinea to collect any living creatures from the sea floor. Live shell photography is more satisfying and I have many regrets that I did not start my photography of shells sooner. What pictures I have missed! We do encourage an interest in finding shells, not just because of the challenge of the hunt and the thrill of discovery – and the beautiful photographic images which can be made, but because the very process of looking for shells changes your way of looking at the entire marine world. It is a fast track to being able to see underwater, not just shells, but all those other creatures that make diving so fascinating.


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