Tunicates

Below are a few examples of tunicates living on Oregon’s exposed rocky shores or washed up on the beaches. The photos are from northern Oregon unless noted. My tunicate identification needs improvement, so I’m starting with just a few (very few!) distinctive forms. Organization-wise, I loosely follow Lamb and Hanby (2005). I refer to WoRMS for scientific names, and if I use common names, they’re my choice. The books, field guides, and identification resources listed at the bottom of the page cover the tunicates shown below and many more.

Let there be tunicates!

Styela
While there is a bit of Pacific Northwest Styela diversity, I’m pretty sure the examples below are Styela montereyensis.

Partially submerged Styela montereyensis among Laminaria sinclairii.
It’s not uncommon to find Styela among Laminaria sinclairii
One Styela montereyensis on a bed of Phyllospadix.
Styela nestled in the surfgrass
One Styela submerged on the edge of a tidepool.
At the edge of a tidepool
One Styela exposed by the low tide. Corallines and giant green anemones in the background.
Often found on low walls where they hang down when exposed
Two Styela montereyensis hanging down on an exposed low wall. Corallines and giant green anemones in the background.
Styela montereyensis is sometimes called long-stalked sea squirt
***

Below are two compound tunicates—well, I think they are—I’ve found attached to Laminaria sinclairii stipes.

In the left-hand panel, solid feeling orangish-yellow lobed globs or spheres, usually down near the base of stipes. In the right-hand panel, uniquely shaped ruffled colonies, generally widest at the end nearest the base of the stipe.

Lobed globs or spheres attached near the base of Laminaria sinclairii stipes.
Ruffled colonies attached near the base of Laminaria sinclairii stipes.
***

Thetys vagina
This large salp washes up on the beaches from time to time.

One individual vagina salp on the sand.
When I saw my first Thetys, I did not know what it was
One individual vagina salp on the sand; it's longer than the 15 cm ruler provided for scale.
If this one looks a little odd, it’s frozen on a chilly morning | Ruler for scale
One individual vagina salp on the sand.
Thetys, freshly arrived
***

Strandings of this two-inch-long salp occur from time to time. (These stranded individuals slightly exceeded two inches in length.). They resemble, to a degree, examples of Salpa fusiformis posted on iNaturalist, but as is usually the case, there are alternatives.

Salp stranded on the moist sand.
Salp stranded on the moist sand.
Closeup of the stomach end (I think) of a salp stranded on the moist sand.
Salp resting on two middle fingers of a human hand. Beach sand and a few pebbles behind.
***

References

Gotshall, D. W. 2005. Guide to Marine Invertebrates, Alaska to Baja California 2nd Edition (Revised). Shoreline Press.
Harbo, R. M. 2011. Whelks to Whales: Coastal Marine Life of the Pacific Northwest. 2nd ed. Harbour Publishing Co.
Jensen, G. C. 1995. Pacific Coast Crabs and Shrimps. Sea Challengers, Monterey.
Kozloff, E. N. 1993. Seashore Life of the Northern Pacific Coast. 3rd ed. University of Washington Press.
Lamb, A. and B. P. Hanby. 2005. Marine Life of the Pacific Northwest. Harbour Publishing.
Sept. J. D. 2019. The New Beachcomber’s Guide to the Pacific Northwest. Harbour Publishing.


Online Resources

Biodiversity of the Central Coast’s Tunicates page. Accessed June 26, 2023.

Friends of Netarts Bay WEBS Tunicates page. Accessed June 26, 2023.

It’s worth scrolling down to tunicates in Common Sea Life of Southeastern Alaska: A field guide by Aaron Baldwin & Paul Norwood. Accessed June 26, 2023.

For invasives, have a look at Invasive Tunicates in the Pacific Northwest. Accessed June 26, 2023.

The Marine Detective’s post on salps is wonderful. Accessed June 26, 2023.

Brian Catelli (2002, as edited). Styela montereyensis. Invertebrates of the Salish Sea. Rosario Beach Marine Laboratory. Accessed June 26, 2023.


I updated this page on June 26, 2023