The gelatinous sea creatures make long chains that look like twinkling lights in the water.
Photographer Heather Hamilton has shared incredible footage of her swimming through a salp bloom in Cornwall, south-west England.
“The early morning light meant that the salps glistened, looking like fairy light,” she says on Instagram.
“Salps are strange relatives of sea squirts that live in the open oceans filter feeding, often in chains. These chains create fairy light-like structures in the water,” explains the Cornwall Wildlife Trust on its website.
This is the second year Hamilton has seen this salp bloom. She says she feels “so lucky” that she “got to dive through the magic once again”.
“Salps are such a strange but incredible animal and not much is known about them, especially in the UK,” she adds via email.
“Does this mean salps will become an annual visitor to UK waters?” she wonders.
Images and videos: Heather Hamilton @cornwallunderwater / cornwallunderwater.com
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