The sea nettle, a glimmer of light in the dark

by Eric Wander

The sea nettle, a glimmer of light in the dark

In the dark water of an aquarium, an almost alien-like creature suddenly seems to float by. The sea nettle (Chrysaora pacifica) moves calmly through the water, its tentacles dancing gracefully behind its body. Against the black background, the creature almost seems to glow.

Yet this mysterious appearance is mainly due to the light falling on the translucent parts of its body. This beautifully highlights the jellyfish’s delicate structures, creating an almost fairy-tale-like image.

A jellyfish has no bones, no brain and no heart as we know them. Yet it is a remarkably successful animal. Jellyfish have been moving through the oceans for hundreds of millions of years. The sea nettle uses its tentacles to catch food. These contain special stinging cells that can deliver a toxic sting upon contact.

In the aquarium, this seems to pose little threat. On the contrary: its gentle movements and translucent body make the sea nettle almost mesmerising to watch. Every movement is dictated by the rhythm of the water and the gentle pulsations of its body.

In this way, a dark aquarium is transformed into a sort of underwater stage. No set, no music and no light show – just a jellyfish floating slowly by, demonstrating just how extraordinary nature can sometimes be.