Dawson's Sun Star (Solaster dawsoni) is one of the least common of all the intertidal sea stars on the Southern Oregon coast, and is found only at or below the extreme low-tide mark. We saw our very first one at a -2.4 tide (the lowest tide of 2007), and we briefly thought we had discovered a new species! They can grow to 14" across, and have between 8 and 15 arms. The Dawson Sun Star below has 13 arms but is only 8-9 inches in diameter. Its arms are approximately the same length as the diameter of its central disk.
The Dawson Sun Star is a voracious predator of other Echinoderms (i.e., other species of sea stars, sea urchins and sea cumbers), and its favorite prey is the Stimpson Star (Solaster stimpsoni). Other sea stars leave immediately when they sense a Dawson Sun Star is nearby. When the Dawson is about to attack its prey, it raises its two forward arms and lunges at the unfortunate victim.
The Dawson resembles a Sunflower Star (Pycnopodia helianthoides) in shape, but the texture of the skin is totally different. A Sunflower Star feels almost like fleece...very soft, while the Dawson Sun Star is much harder, like a bat star or a blood star, but is rougher to the touch. Their color ranges from orange to a purplish gray. The Dawson Sun Star in the photo below is only 5" in diameter.
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