Starfishes

Below are examples of starfishes I’ve run across on Pacific Northwest shores. It’s a scant list. Nevertheless, my organization follows Lamb and Hanby (2005). The common names are my choice. I refer to WoRMS for scientific names, and I learn a ton by browsing the natural history riches in Kozloff (1993). Biodiversity of the Central Coast’s Echinoderms page is full of great information on starfishes. For more information, the books, field guides, and other resources listed at the bottom of the page cover the sea stars I show below.

Pisaster ochraceus
No tidepool invertebrate on northeastern Pacific shores evokes more human fascination and connection. When Pisaster’s doing well, all seems right with the world.

In the foreground, a lone Pisaster exposed by low tide (surrounded by kelp). The view is out to the surf zone on a gray, misty day.
Pisaster will pose for you
The view is distant enough to encompass twenty or more closely-packed Pisaster at the sand rock interface. There are a few large giant green anemones in the scene.
You’ll sometimes see aggregations of P. ochraceus where rock meets sand
In the foreground, a large orange Pisaster at the base of the mussel bed (exposed by low tide). The view is along the exposed mussel bed. In the distance you get a sense of zonation.
Pisaster ochraceus, very much at home at the base of the mussel bed
A lone electric indigo-colored Pisaster exposed at low tide. The scene also has lots or corallines and giant green anemones.
Electric indigo
Intimate scene of two baby Pisaster on two adjacent mussels within the bed.
The mussel beds can be bursting with babies
***

Leptasterias, six-rayed stars
I think the examples shown here are what people refer to as L. hexactis, but this is a complex with unclear boundaries, so I’ll leave it at Leptasterias for now.

A dark beauty in a crevice with some neighbors
Leptasterias among the sponges, anemones, and barnacles
A lone Leptasterias is smaller than a nearby Monterey dorid
Leptasterias on a vertical wall, associating with barnacles, a nudibranch, and Pisaster
Leptasterias in a sand-filled pool with a sculpin and some pink-tipped and giant green anemones
I didn’t even notice the sculpin
***

Pycnopodia helianthoides
I haven’t encountered these predators in the wild intertidal since April 2013.

Pycnopodia helianthoides usually has about 20 rays
Pycnopodia helianthoides are also known as sunflower stars


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.

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. 2009. The Beachcomber’s Guide to Seashore Life in the Pacific Northwest. Revised ed. Harbour Publishing.


Online Resources

Biodiversity of the Central Coast’s Echinoderms page is full of great information on Pacific Northwest starfishes.


This page was updated April 14, 2022