Christmas Tree Worm - Oceana

Corals and Other Invertebrates

Christmas Tree Worm

Spirobranchus giganteus




Tropical Coral Reefs

Feeding Habits

Omnivore Filter Feeder


Phylum Annelid (ringed worms), Family Serpulidae (tube building worms)


Christmas Tree Worms are ciliary feeders, which means they use cilia, tiny-hair-like bristles on their appendages, to catch food as it passes by. The food then passes down a groove pushed by their ciliary tracts, which are lines of tiny hair-like extensions on the sources of cells that create water currents to direct digestion. Through this method the worms will also take in sand, storing those grains away in separate sacs to assist in building tubes to anchor them to the corals.2

Once Christmas Tree Worms find a coral to live in, they don’t move much and their brightly colored plumes make them easy to spot in the ocean.1 When startled, these worms will rapidly retreat back into their burrows, later poking a small amount of their bristles back out of their burrows to determine if the danger has passed.

Female worms release eggs into the water where male worms have released sperm. The fertilized eggs develop into larvae that then settle on coral heads and begin burrowing in to form their homes

Fun Facts About Christmas Tree Worms

1. Christmas Tree Worms average only about 1.5 inches in length.

2. Up to two-thirds of the worm is anchored in the coral when its plumes are visible.

3. Christmas Tree Worms’ fir tree like appendages are also used for respiration, collecting oxygen from the currents.

4. Christmas Tree Worms have been found burrowing into giant clams instead of coral.2

5. Christmas Tree Worms rarely, if ever, move from their burrows.

Engage Youth with Sailors for the Sea

Oceana joined forces with Sailors for the Sea, an ocean conservation organization dedicated to educating and engaging the world’s boating community. Sailors for the Sea developed the KELP (Kids Environmental Lesson Plans) program to create the next generation of ocean stewards. Click here or below to download hands-on marine science activities for kids.

Kids Environmental Lesson Plans



2. Marine Bio Conservation Society