Blue background

  

Last week I came across an Ochre Sea Star (Pisaster ochraceus) that was noticeably blue.  It's a little hard to tell from the photo above, but hopefully you can see the blueish background coloration among the clusters of white spines.

We've been monitoring Pisaster for over a decade and have observed thousands of individuals during that time, but I can't recall seeing a blue adult sea star until now.  The most common colors are orange, brown, and purple, but this blue individual seemed unusual, so I took a quick photo for the record.

That said, we often see juveniles with blueish coloration — see photos below from this past winter:

 

 

 

I've often wondered if the blue juveniles gradually turn purple, and perhaps some do, but the blue adult in the first photo shows that sometimes the adults can be blue, too!