You might have heard or noticed that there have been a lot of By-the-wind Sailors (Velella velella) washing ashore on local beaches recently. Here's a photo from Bodega Head today, 31 March 2025.
Numbers of Velella vary from year to year, but this is a relatively common phenomenon during the spring, especially when there are strong west winds.
Sometimes when there are lots of Velella, there could be other species from farther offshore mixed in with them, so I often take a closer look to see if anything else stands out.
Interestingly, when I was looking at one Velella that was still floating, it looked like there was something on the "deck" (the skirt or mantle):
And with an even closer view, I realized what it was: