There are many, many things that can go wrong as you lay thousands of miles of fiber optic cable along the ocean's floor. Earthquakes can rip things up, as can fishing hooks. But now we know of a new threat: Shark attacks.

According to Network World, Google Product Manager Dan Belcher told folks at a Google marketing event in Boston last week that Google ensures its cable is sheathed in a Kevlar-like protective coating to keep the sharks from chomping through the line. Turns out this is standard operating procedure among undersea cable-layers, who must take a number of steps to keep aquatic life from harming (or being harmed by) data cables.

We asked Google about this, and if they have any idea why sharks would want to eat fiber optic cables, but they had nothing to say. But apparently it's a thing, as you can see in the video below.

As Google expands its online empire, undersea cables are becoming an increasingly important part of the plan. The company has invested in two major undersea cables connecting the western US to Asia, and a third cable that extends Google's network within Asia. That's where the big data bottleneck is these days, and a lack of fiber connectivity can push up market prices for moving data between the two continents. That is unless, like Google, you have access to your very own cables.

We've long known squirrels are a major problem to anyone laying cable, but according to a report by the International Cable Protection Committee cable bites—by sharks and other fish—remain a surprisingly persistent problem. In the 1980s, a deep-ocean fiber-optic cable was cut four times. Researchers blame crocodile sharks for those attacks after finding teeth in the cable.

The cable protection folks really have no idea why sharks bite cables either, although some suggest it may be due to "electro magnetic fields from a suspended cable strumming in currents," they say in their report.

>If you had just a piece of plastic out there shaped like a cable, there's a good chance they'd bite that too.

Sharks, like other animals, can detect magnetic fields – and they have miniature volt sensors in their mouths that they use to detect prey and mates. But there's a simpler explanation, says Chris Lowe, the professor who runs California State University, Long Beach's, Shark Lab. They may simply be curious. "If you had just a piece of plastic out there shaped like a cable, there's a good chance they'd bite that too." But even an exploratory nibble is enough to cause some serious trouble. "Just a little bite is enough to get through the jacket, damage the fibers and then you're screwed," Lowe says.

More recently, Level 3 Communications technicians did come across a three foot long shark in a trench near its fiber cable—two miles inland—in the aftermath of Hurricane Katrina. Maybe it was looking for a bite.