(13-01-10) The ghostly vision of a wreck lying on the seabed is one of the most evocative images of underwater exploration. We are going to give the keys to fully enjoy in a safety way this type of diving.

    The imprint of man sailing across the seas of the planet dates back almost to the dawn of time, and the wreckage of the different vessels has spread all seabeds. Ships of every age, shape and condition await submarines explorers, eager for new experiences.

    Shipwrecks are part of underwater ecosystems, acting as real magnets for life. The presence of a fixed structure on the bottom of the sea makes it become a sort of obligatory stop for the thousands of marine life forms that wander through the liquid element.

    It can be seen just looking at the enormous speed with which a boat sunk recently begins to be covered by different forms. In the tropical seas corals, heavy and soft, are in charge of the colonization, while in our latitudes algae, sponges, anemones, gorgonians and other small creatures are the first settlers.

    These will attract other, finishing the entire pyramid. Molluscs, crustaceans, small fish and larger fish will gradually taking over what was once wood and iron; building in many cases a true oasis, so it will be enough to move away some few meters from the hull to see how animal concentration decreases noticeably.

    There are many inhabitants in wrecks. Roughly, we can see gregarious fishes that gather in small schools looking for wreck protection. In tropical waters “glass fish” are usually one of the common guests, while in the Mediterranean they are swallowtail seaperch or goldcrest. In the Canary Islands waters bastard grunts are the main characters, forming impressive concentrations in some wrecks.

    Territorial animals also seek every nook and cranny of the shipwreck to build their shelter; conger eel, moray eels or big groupers are common inhabitants. Finally, manta rays, sharps and barracudas are common in the surroundings of this concentration of life.

New shipwrecks   

    Apart from “natural” shipwrecks, various boats and even planes have recently been sunk, some for recovering some areas, as we mentioned above, and others for a recreational purpose to promote underwater tourism. In these cases the place for sinking are chosen, places not very deep and protected for offering the possibility to dive most of the days.

    An important issue is that in these cases the ship is prepared to avoid any problem to divers. Polluting agents have been removed and also cables and dangerous areas. What happens is that also some of the most typical elements of ships, the ones that have some value in the market, are also removed, such as propellers, rudders or binnacle. It is safer but we lose “seafaring characteristics”.

Exploring shipwrecks

    Exploring a sunken ship always requires some special precautions. As in any dive, planning plays an important role. It is recommended to be informed in advance about the features of the wreck, and it is especially interesting to have a drawing or a plan.

    It is important to bear in mind that entering a ship is always a potentially dangerous dive: we dive in confined environments, where there is roof, and the possibilities to escape are reduced. If we are going to get in good buoyancy control is essential. Wrecks usually have a lot of sediment, so a wild flutter can cause great haze, as happens in a cave, with fatal consequences.

    On the other hand, rusty iron become real sharp knives that can cause serious injuries, therefore a perfect hydrostatic equilibrium imposes. Using a guide wire may be a good option. Obviously, a good focus is always essential for an internal examination of a wreck. We have to remember that the different educational organizations offer specialty courses on such wreck diving.

    Another peculiarity with wrecks is the possibility of having a dangerous load. This is particularly important in warships. We can still find some with explosives that, despite the time since they sunk, remain being very dangerous. It is the famous case of the Umbriain Sudan or of many of the wrecks of Truk Lagoon. In these cases we must be very careful and not touching anything.

    In this same vein, we have to keep in mind that, although we do not touch anything and do not suffer any snags, our own bubbles can make air chambers that destabilize the ship or any part of its load. Also, these bubbles of air, when hitting the roof, make sediment landslides and water becomes turbid.

Respect for the past

    Finally, we have to appeal to ethical conscience of all divers. We have to be extremely respectful to the remains we find. Some can have archaeological value, if so, we must limit the dive and tell the authorities our findings. In this case, not doing it and taking some remains are an offence appeared in the Penal Code.

    But in any case we must be respectful just for principles and to let the rest of divers continuous enjoying this underwater spectacle. Images such as the ones of the very famous Thistlegorm, which is being literally ripped to pieces by unscrupulous hordes of centres and divers, should not be repeated any more. Seeing the current images of destruction, and comparing them to the ones that many of us keep in our memory, it is perfectly understandable that Cousteau, its finder, did not publish its location.

   Last, we have to bear in mind that in many cases the wrecks we see are the result of a tragedy, and many people died in it, so a little respect is important. In this sense, it is very interesting the campaign that PADI carries out in the Project AWARE to protect shipwrecks “Respect our wrecks” (www.projectaware.org).

Text and pictures: Juan Carlos García