I wonder how three similar and closely related surfperch can live together on homogenous sandy beaches. How do they subdivide theoutershores? One solution might be partitioning their food. To study this, I’m learning to identify what they eat; surf perch and their competitors.
Above is one of the first surfperch food items I ever examined. It remains unidentified, so if you know what it is, I would appreciate hearing from you.
Much of the surfperch prey is crustacean. I’ve found lots of smooth bay shrimp, Lissocrangon stylirostris and Pacific mole crabs, Emerita analoga, in the stomachs of surfperch.
Pentidotea, an isodpod, is a common food item. I should be able to identify this one by the shape of the telson, but so far I’m stumped. I’m hoping somebody will help me out.
Surfperch can’t resist bright orange crustacean eggs. If you were a fisher, would you consider using orange lures?
Pollicipes polymerus and Pentidotea affiliate with rocky habitats, so we know surfperch hit the rocks to forage when conditions permit.
Staghorn sculpin and sand sole arrive on the beaches in summer, just before surfperch give birth to their babies. Are they predators on baby surf perch, or competitors for crustaceans?
Speaking of competitors, here’s something you don’t see every day. An theoutershores reader sent me the following link: http://www.flickr.com/photos/cambriabird/8354888665/in/photostream
This footage was taken on an outgoing tide, mid-morning on January 6, 2013. I’ve never seen anything like this, but others have, particularly near where this occurred, in San Luis Obispo County, California. It looks to me like these birds are dabbling for crustaceans in the surf. What do you think?
Note: I updated the photos and lightly edited the text on October 21, 2017.