Back in Blue

They're back!  Last summer and fall we encountered these barnacles for the first time.  There have been so many By-the-wind Sailors (Velella velella) washing up recently that we wondered if the barnacles might appear again.  Tonight we spotted at least 2 dozen Blue Buoy Barnacles (Dosima fascicularis) on Salmon Creek Beach.

 

I wrote about Blue Buoy Barnacles last year, so I'll refer you to those posts to learn more about this fascinating species (see below):

- Introduction to Blue Buoy Barnacles on 31 August 2014.

- More details about Blue Buoy Barnacles on 23 September 2014.

And here are a few more pictures from 28 May 2015.

We noticed a few differences this spring compared to last summer/fall, some of which might have to do with the time of year.

Some of these barnacles were on Velella that were fairly complete, while last year the barnacles were attached to only small pieces of Velella and many of the barnacles had made their own floats.

 

Here's one that was starting to produce its float material — the white foamy mass at the base of the blue stalk:

 

Some of the Blue Buoy Barnacles we encountered tonight were quite small.  The largest were 15 mm long (the length of the plates that enclose the body, not including the stalk), while the smallest were only ~5 mm long.

 

We don't know how long these wonderful, pelagic blue barnacles will be visible in this area, but it's worth watching for them if you're walking local beaches.  Let me know if you find some!

P.S.  Don't miss this video featuring Blue Buoy Barnacles:

https://www.youtube.com/watch?v=8KPxBr3Ej5Q