Underwater decor?

Christmas Tree worms, found in the coral reefs of Saint Martin's Island, may look like underwater holiday decorations, but are actually tube-building worms! Widely distributed throughout the world's tropical oceans, they're known to occur from the Caribbean to the Indo-Pacific and find habitat mostly in corals.

The worm's most distinct feature are the two brightly coloured "crowns" shaped like Christmas trees, which are actually specialised mouth appendages. Each spiral crown has feather-like tentacles that help it breathe and trap food – typically microscopic plants or phytoplankton floating in the water – which they consume by filter feeding.

PHOTO: SHARIF SARWAR

As these worms are sedentary, once they find a place they like, they don't like to budge from there. However, when startled, they rapidly retract into their burrows to avoid potential predators. While there are no conservation activities for the Christmas Tree worms, owing to their vast distribution, water pollution can damage their habitats and shorten their lifespans.