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Home > Do Deep-Sea Fish Explode When They Are Brought to the Surface?

Do Deep-Sea Fish Explode When They Are Brought to the Surface?

No. Deep-sea fish do not explode when brought to the surface.

But some fish have an internal air sac that may expand when they rise. Because of the expansion of their air sac, there is a risk that their insides will be pushed out through their mouth, thereby killing them.

A Fangtooth (Anoplogaster cornuta).

This deep-sea fish is a Fangtooth. Its scientific name is Anoplogaster cornuta.

The Problem of Expanding Air Sacs

Some deep-sea fish have a swim bladder inside their body. The swim bladder is a gas-filled sac below the backbone that acts as an internal floatation device. It helps the fish maintain its depth in the ocean without much effort.

A swim bladder.

A swim bladder.

If the fish rises quickly from the deep, the pressure on its body from the surrounding water decreases quickly.

The pressure decreases on the swim bladder as well. This allows the gases inside the swim bladder to spread out and fill more space, so the swim bladder expands.

This is a bit like putting compressed air from a tank into a balloon. As the air leaves the tank, it is able to take up more space, and so it causes the balloon to expand.

When this happens in a fish, the expanding bladder gets so much larger that some of the fish’s insides are forced out through its mouth, and then it dies.

A pile of dead fish (Coryphaenoides armatus). Internal organs protrude from some of their mouths.

These fish live at a depth of 4300 metres. When they surfaced, their swim bladder expanded and pushed internal organs out of their mouth.

Avoiding the Problem

Some deep-sea fish have no swim bladder, or air-filled cavities of any sort, and so do not face that problem.

But they still wouldn’t be comfortable living anywhere except at the depths of the ocean. Even if a fish could survive the difference in pressure at the surface, the differences in temperature, light and other factors would pose serious challenges because deep-sea fish are not adapted to those conditions

Heat Wave!

Change in temperature is problem that deep-sea fish would face if they were to come near the surface.

  • Because deep-sea fish are used to the colder temperature of 1 or 2 degrees Celsius, their bodies have trouble functioning in the warmer temperature near the surface.
  • If they were brought up to warmer water, all the chemical reactions in their body would speed up and they would use all their energy very quickly.
  • This would leave the deep-sea fish exhausted.

Who belongs to these big teeth?

A deep-sea fish of the genus Melanocoetus.

Find out on page 3.

Q: Do we have deep-sea creatures in Canada?

Forillon National Park. A: Yes, we do!

Canada is a country of coasts. It is bordered on three sides by oceans: the Atlantic, the Pacific and the Arctic. Parks Canada is working hard to preserve habitats along these coasts. This government agency has classified many coastal areas and waters into 29 distinct marine regions.

One region where deep-sea creatures can be found is called the Newfoundland Shelf. There, some places are nearly 800 metres deep!

The Newfoundland Shelf waters are an important habitat for the Atlantic Cod.

Find out more about the 29 marine regions on the Parks Canada web site.

Living in a Difficult Place

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