Do sharks like biting on submarine internet cables? The captain of a cable ship reveals all

Guillaume Le Saux on the bridge, where it all happens.
Guillaume Le Saux on the bridge, where it all happens.
Image: Quartz/Joon Ian Wong
We may earn a commission from links on this page.

That the internet is physical can be hard to grasp. Few people have experienced this fact as viscerally as Guillaume Le Saux, captain of a ship named the Pierre de Fermat. It’s a state-of-the-art vessel that’s part of a fleet owned by French telecom company Orange, designed to lay and repair the optical fiber cables that criss-cross the world’s seabeds.

The life of a cable-ship captain is pretty intense. Le Saux is on constant alert, ready to be dispatched to the middle of an ocean with a couple of hours’ notice. This can sometimes mean sailing into 20-foot waves, receiving ransoms, or fixing up a shark’s chew toy.

When Le Saux arrives at the appointed spot at sea, he and his crew deploy Hector, the ship’s seven ton underwater robot, which will travel to the seabed, sometimes at depths of 5,000 meters. Hector’s job is to inspect the damage, bury newly laid cable on the sea-floor, or help bring damaged sections up to the ship’s jointing room, all controlled from the ship’s deck.

On the day we meet, the Pierre de Fermat is anchored at Portland port, a commercial port on England’s south coast on the English Channel. It has just weathered a rough night at sea traveling from Brest in northern France. It’s a rare opportunity to board the ship, which is difficult to pin down because of its rapid deployments, and Orange’s PR team has arranged for a tour of the 80-person capacity vessel with just a couple of days’ notice.

The Pierre de Fermat cable ship
The Pierre de Fermat
Image: Orange Marine

Getting on the ship requires walking up an aluminum gangplank nearly three stories high. On board, the crew is enjoying a lunch with wine, which is only allowed on Thursdays and Sundays. Below deck, I watch two kilometers of submarine cable being loaded into one of the ship’s nearly three-stories-high tanks. They have to be guided into place by hand by a team of six workers. Previous attempts to use mechanized means of loading and coiling have proved less efficient, Le Saux explained.

Once the cable was loaded, the Pierre de Fermat would embark on a three-week-long mission in the North Sea to repair British Telecom cables connecting the United Kingdom and the Netherlands. The ship was just hours away from departing when I spoke to Le Saux about life at sea safeguarding the world’s data links in the most literal way possible, in an age of wireless data transfer and the rise of the cloud.

Quartz: Is it true that sharks attack submarine cables?

Guillaume Le Saux: It’s true, but it’s very rare. It’s not very often. Sharks can smell the electricity, the electro-magnetic radiation, and because they seem to be very curious, they try to bite the cable. When the water is warm, it depends on the area, we have some specific cable protected with a sort of aluminum sheet to avoid the radiation [being sensed by sharks] and this cable is known as the “fish bite” cable. They cannot feel the electro-magnetic radiation so they don’t see the cable.

What about whales?

No, They cannot bite it or hurt it, because the cable is laid on the seabed. So we cannot imagine whales passing under the cable for example.

Are cables laid on the seabed even in the deepest parts of the ocean?

When engineers prepare the cabling operation, they try to determine the best way for the cable to go on the seabed in order not to consume too much cable. They try to avoid the area with a lot of [undersea] mountains, for example. But if you have to go from Europe to the United States, you have to pass through the middle of the Atlantic, you will have to pass through a 5,000 meter water depth. At any time, the cable is lying on the seabed. It’s part of our job to ensure the ship is traveling at a good speed [of five to six knots], to lay the cable, to be sure the cable is laying on the seabed.

What are some of the security measures in place around these cables?

The cables are very strategic. It’s very important for communications in all countries. So most of the time, countries where we lay the cable are involved also in the protection of this cable. So it’s in our interest, it’s in their interest, that the cable is protected.

One of the most important parts of the job is when we send the cable to the beach. The ship arrives close to the beach and we send the cable to the beach. We have some police to prevent everybody crowding around the cable. But from time to time, somebody tries to steal the cable, to break it.

Has this happened to you before?

In Indonesia, yeah, but it’s not very often. It’s very rare that the cable is cut intentionally.

We were laying the cable, we did the shore-end, so we sent the cable to the beach, and then we left to start the cabling operation. Some fishermen arrived, they picked up the cable from the beach, they picked up 200 meters of cable, coiled it on their small little fishing boat, they took a picture, they sent it to us, and they asked for ransom. The cable wasn’t active, so we repaired the cable. We cannot imagine that we pay a ransom to anybody trying to steal the cable.

That’s the policy?


Your job is repairing cables. How do they get damaged?

The cables are damaged, maybe 80% of the time, due to human activities. Of the 80% of human activities, you have maybe 80% fishing activities. Most of the time it’s a trawler trawling the seabed. These are big trawlers, for example, in the North Sea, the capacity of the trawler is like if a trawler towed two London buses on the seabed, to give you a sort of a picture. They tow two London buses on the seabed, so it’s very aggressive for the seabed and for the cable also.

You have also the anchor. When you are approaching a harbor, some vessels are anchoring, they can damage the cable [it’s the remaining 20% of human activities]. It’s not so rare, because sometimes a ship’s captain, like me, make some mistake, drops anchor at the wrong position. Some countries in Africa, the anchor area is in the cable zone. Sometimes you have some typhoon, tempest, hurricane; the ship drops anchor, the ship moves and catches the cable. So it’s not so rare, it’s quite common.

The other damage is from earth activity, for example, years ago, you have the tsunami in Asia, some cable ships worked for months and months to repair the cables on the seabed.

How much notice do you get before you have to sail to a repair spot?

The contract for us, we are at 24-hour notice to leave the base-port to repair a cable. Most part of the time, [a cable owner] needs only a few hours to detect a fault in a cable. So the cable owner phones the hotline for us, we mobilize the ship and we sail. We have to sail in less than 24 hours, and for the most part of the time, we are 24 to 48 hours away, from the base-port to the cable area.

How did you end up in this line of work?

I’ve spent four and a half years as captain. But before that I was chief officer, I was also chief engineer, I was also mate, so it’s about 16 years now I am in this job. I arrived [in the industry] as a cadet, mate, and I’ve spent all my career on a cable ship basically.

How has the industry changed in those 16 years?

Concentration of companies, less activity because the cables are now [larger] capacity. So when you install a cable, you have a lot of capacity, so you don’t have to lay too much cable. Yes, it has changed. Now it’s developed by other people, for example, the Chinese now have cable ships. Fifteen years ago they don’t have any cable ships.

Do you think we’ll end up at a point where we don’t need cables for the internet?

I’m quite sure, no. We will always need cables. Because it’s a huge capacity, it’s less expensive than satellite, so I think we always need cables.

And how’s your internet on this ship?

Poor! (laughs) Because we don’t have internet from the cable! We have internet from satellite.