Light fantastic under the sea
THE deep, dark sea is full of colourful glowing light displays. Georgia de Jong Cleyndert, Senior Marine Conservation Officer for the North West Wildlife Trust, tells us all about bioluminescent creatures.
Why do deep sea creatures light up?
They do it for many different reasons. Sometimes it can be a quick and sudden glow in defence to ward off predators. Some creatures use a longer glow to attract prey or to communicate and attract mates.
How do they glow?
Bioluminescent creatures actually create light. They can do this in two ways: either through a chemical reaction or from bacteria living on their skin.
Are bioluminescent creatures in the seas all over the world?
Marine biologists estimate that 7090% of species living in the deep sea are able to produce light. They exist all over the world and particularly in very deep waters.
Do they glow in different colours?
Light is made up of different coloured radiation. Blue radiation is the colour that travels best and reaches the greatest distance. Red radiation is quickly absorbed. Almost all organisms living in the deep sea can only see the green and blue regions of the spectrum.
Their bioluminescence is also usually just blue or green.
Have you seen a bioluminescent sea creature?
The most common bioluminescent creatures are the microscopic, plantlike Dinoflagellates that are found in warm tropical bays on the surface waters. I was lucky to experience it on holiday a few years ago.
What is the smallest bioluminescent sea creature and which is the largest?
Microscopic, plant-like dinoflagellates are single-celled plankton that are bioluminescent. The kitefin shark grows to a length of almost 2m making it the largest known bioluminescent vertebrate. Giant squid, which get much bigger (up to 10m long), are also known to produce light to hunt prey.
What are some of the weirdest glowing sea creatures?
There’s a squid that can drop one of its arms, which will glow. The predator swims towards the arm while the squid is able to get away.