The tide pool sculpin is common in tide pools in rocky areas and under rocks.
Look for a small, slender fish that typically is not more than 4 inches long.
Sculpins can vary in coloring from red-brown to green. They are usually striped with 5 irregular dark saddles across the back.
If you can see the gill cover, look for a single, forked spine on it.
Sculpins seem to be tolerant to changes in tide pool water temperature throughout the day.
They can also use their sense of “smell” to find their way back to their original tide pool if displaced.
Pacific Wonder Tracker 
The second picture is of a plainfin midshipman
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Greg, thanks again for your correction. I downloaded your free e-book on Pacific northwest sculpins. https://molamarine.com/ It is an amazing resource and emphasizes just how much I have to learn! Thank you for sharing your knowledge and images in the book.
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