June is LGBTQ+ Pride Month, and in the spirit of celebrating diversity — both invertebrate and human — we’re featuring a critter that wears its rainbow colors with pride every day of the year. Meet one of Puget Sound’s most beautiful creatures: the ornate tube worm, Diopatra ornata. Diopatra ornata collected from subtidal sediments at Nisqually Reach.
Breathe with me
Like many other species of polychaetes, or marine segmented worms, D. ornata has gill structures called branchiae on each segment, which help pull oxygen from the surrounding water and sediment. In D. ornata, the branchiae are distinctly spiraled and look like frilly trees or ferns running down either side of its iridescent body. The bright red color of the branchiae comes from the blood vessels inside — if you look closely at the live worm, you can see them expanding and contracting to help circulate blood throughout the body.
Fancy digs
Photo courtesy of Jeff Adams, Washington SeaGrant.
The tube’s adornments, which the worm sticks on with mucus, not only serve as camouflage from predators, but also encourage small animals to colonize the outside. In some parts of D. ornata’s range, especially off the central California coast, the tubes occur in great densities, forming mats that provide complex habitat for macroalgae (seaweed) and other animals. The little communities of organisms on the outside of the tubes may also serve as a built-in snack bar when the worms get hungry.
Left: A shell-covered Diopatra ornata tube protrudes from sandy sediment
Jaw-dropping
Ventral
Diopatra like to build their tubes in sand rather than fine mud, so in Puget Sound, we see them most frequently where the sediment is coarse, such as around Nisqually Reach and East Anderson Island. So next time you’re walking on the beach at low tide and spot a large debris-covered tube sticking out of the sand, chances are you’ve encountered the home of one of these ornate beauties!
Critter of the Month
Our benthic taxonomists, Dany and Angela, are scientists who identify and count the benthic (sediment-dwelling) organisms in our samples as part of our Marine Sediment Monitoring Program. We track the numbers and types of species we see in order to understand the health of Puget Sound and detect changes over time.
Dany and Angela share their discoveries by bringing us a Benthic Critter of the Month. These posts will give you a peek into the life of Puget Sound’s least-known inhabitants. We’ll share details on identification, habitat, life history, and the role each critter plays in the sediment community. Can't get enough benthos? See photos from our Eyes Under Puget Sound collection on Flickr.