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Dock Fouling at Bremerton Marina

A couple weeks back I decided to do another tour de foul, where I select multiple potential dock fouling locations to visit in a single day. Looking at the map I could see numerous marinas between Bremerton and Bainbridge and plotted out a course with five spots to stop. After my last tour de foul of Whidbey Island I was anticipating a mixed bag- maybe a few really amazing finds but mostly more of what I had seen before. I was in for a treat.

Bremerton Marina

The marina is a short distance north of the ferry. Whenever approaching a new marina I always run the risk that it will be completely inaccessible to the public. Bremerton Marina has large sections not open to the public, but I was delighted to find what might be the largest public area of floating dock in Puget Sound. Immediately when I got down to the water I was struck by how many huge plumose anemones were visible, in bright whites and oranges, with substantial feature duster worm colonies interspersed. This was a good sign. Curiously most of the anemones had their "defense" tentacles out, which I rarely observe. Quickly I was drawn to a organism that I couldn't identify. It appeared to be some sort of sea slug but was far larger than any other sea slug I had previously encountered, almost a foot long! The creature had long cerata (the frilly bits) that might lead a casual observer to dismiss it as an anemone. This guy was so obscenely large I struggled to get a good shot of it with my underwater camera and snapped a few images with my cell phone above water. Later I would find out this is a rainbow nudibranch, one of the largest sea slug species.

I was able to halt obsessing over this critter and moved along. Quickly I started seeing numerous thick-horned nudibranchs, in greater abundance than I had seen elsewhere. They were thick among the feather duster worms, buzzing along as they are wont to do.

Further along the marina I noticed something among the feather duster worms. Had it not been for my recent experience seeing the massive sea slug I would have never thought that is what it would turn out to be, but later examining the photos there was no doubt that it was another rainbow nudibranch.

As I continued along the dock I started to notice yet another type of nudibranch. I later ID'ed these as juvenile rainbow nudibranchs. There were very different in appearance, looking similar to orange and white tipped nudibranchs. Until I looked them up I assumed they were a different species.

I visited four other docks that day and saw numerous juveniles at three of them, but no more adults. During that first adventure at Bremerton I ran through an entire camera battery and at that point convinced myself to move own, vowing to return soon. About a week later I was back, excited for another round of unnecessarily big sea-slug viewing. I wasn't disappointed. However, there was an surprise bonus element of jellyfish on my second trip. My friend Allison was the first to spot the lion's mane jellyfish, which I stopped to photograph for some time. After that we started to notice multiple jellyfish that were in the process of getting eaten by sea anemones. Some of the jellyfish were still trying to make an escape but most were too digested to function. I had never seen anything like it. It is one thing knowing intellectually that anemones are voracious predators, it is quite something else to see them in action.

That second visit had another treat in store. During my first visit I had seen one of the adult rainbow nudibranchs swimming, or "dancing" as it is known, through the water. It happened so fast I did a poor job of capturing it on video. I was prepared this second go around. I saw a white form deep in the water that was doing the characteristic movements of a sea slug in motion. I got my camera out and was able to record it swimming all the way up to the bottom of the dock. It was still a tricky endeavor to secure footage, but was an improvement on my first attempt.

Bremerton Marina has become my new "spot" since all the sea slugs at Eddie Vine have apparently vanished. I already plan to go back again this week, while also taking time to really explore Port Orchard Marina- a quick foot ferry ride away.

Please excuse all my silly commentary during my videos. I recommend watching with the sound off!

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