A vivid display of bioluminescence lit up the shores of Jervis Bay in southern NSW on the weekend.

Bioluminescence occurs when living organisms emit light through a chemical reaction inside their body.

The phenomenon can happen in a number of different organisms, including fish, squids, crustaceans and algae, usually as a signal to attract mates or as a defence mechanism to confuse predators.

Image: Bioluminescence at Jervis Bay on the weekend. Source: @james_w_carlson / Instagram

When a large concentration of bioluminescent algae is disturbed by breaking waves at night, the splashing can create an eerie blue glow along the shore.

Image: Bioluminescence at Jervis Bay on the weekend. Source: @petarbphotography / Instagram

After hearing reports of bioluminescence in Jervis Bay last week, photographers and onlookers flocked to the region to witness the spectacle on the weekend.

Image: Bioluminescence at Jervis Bay on the weekend. Source: @teegantagg / Instagram

Bioluminescence can happen in other parts of Australia and in other countries and oceans as well. It's also known to occur throughout the ocean column, from the surface to the otherwise dark depths. Last month, bioluminescence lit up the waves at Glenelg Beach in South Australia.