Winter storms wash mermaid’s purses onto the sandy beaches. I found this one in the fresh wrack on the morning of March 9th. The only dog on the beach beat me to it and that’s why you see those tracks in the sand.
I flipped it over to reveal the view most often shown in photos. Mermaid’s purses are egg cases produced by some skates and sharks. This one is a good-sized specimen.
This is probably the egg case of the big skate. Big skates are common on the Oregon coast. They get several feet long and hang out on and over soft bottoms, usually less than 1000 feet deep. I found a nice photograph of a cleaned-up big skate egg case that’s worth checking out.
I don’t find many mermaid’s purses on the outer shores beaches. Have you ever discovered one?
Note: I updated the photos and lightly edited the text on October 30, 2017. In the years since this post I have not found another mermaids purse on the beach.