I think these are actually pale sea cucumbers, cucumaria pulcherrima.  They grow to be about 2″ long, but most of the ones we saw in the tidepools were less than 1 inch.  Besides texting photos to former naturalists at 6:30 am, (thanks again, Arla!) I am always looking to understand how the things on our beach fit into the whole chain of the ecosystem.  This DNR website is always good for identifying new things.

Echinoderms (literally “spiny skins”) on our beaches include sea stars, urchins, and sand dollars (keyhole urchins.) They all have internal skeletons of some sort, and symmetry in five parts.  These have tube feet along five axes which run the length of their bodies. They are detritus feeders, and their tube feet may help propel them through the sand and their food to their digestive system. According to the Lippsons, authors of Life Along the Inner Coast,

“Sea cucumbers may be the single most plentiful group of organisms in the ocean depths…  Some have toxic substances within their bodies that can repel fishes.

If I google the question, “who eats sea cucumbers?” I come up with the two answers, “really big fish” and “people.”

I was interested in the fact that nothing seemed to be preying on them– a family of least terns was nearby and were not interested at all.  Ghost crabs, which would normally be all over new inhabitants of the tide pools, were also nowhere to be seen.

By yesterday, there appeared to be more cucumbers at the tideline all up and down the beach, and these tiny ones were scattered about.  So, it does appear to be a mortality event.

Bird droppings on the beach showed tiny fragments of what could be the inner skeletons of sea cucumbers: