Yesterday while paddling on the Columbia River, I spotted a small group of seals, or sea lions sunning themselves on a sand bar. They were nearly white–especially one of them, but the others were all a yellowish white. They had fins that they sort of walked on like sea lions, but t;he fins were relatively small. All of the animals were around six feet, or more and I would guess in the five to seven hundred pound range. I’ve looked around on the Internet and couldn’t find any pictures that were quite right. The closest was Antarctic sea lions, but this is a bit out of their range. I wonder if there is such a thing as bleached out California sea lions.
I’ve seen harbor seals as white, but they don’t meet your flipper and size description (which sound like sea lions).
Based on your size observation, sounds more like a stellar sea lion than a California sea lion, but neither really gets white. Stellar do sound lighter than California, as tan to brown color when dry (http://www.marinemammal.org/biology/steller-sea-lion/).
Yeah, we have thousands of Stellers around here, but right now they are hanging more around the coast. The animals I saw certainly weren’t big enough to be adult Stellers, but maybe some bleached out younger ones.
I would prefer that they would go away, but if they stick around, I’ll probably see them again. Next time maybe I’ll have my phone ready and get some pictures.