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We have our oysters at about the 0-1 ft level and they are becoming covered in barnacles (including the aquapurses and grow bags). Is there such a thing as the "barnacle line" and should we move our oysters higher on the beach? How do others deal with barnacles?

Thanks,

Dave

Thanks for your post davidpai. It is great to see new people on the forum.
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There are some thoughts on Barnacles: Generally, in South Puget Sound barnacle larvae will set on your oysters and gear during a 6 week window from the beginning of April through mid-May. So if you can plant after May you should be able to avoid them for that year. As far as elevation, the general rule is that barnacles set above a +2 on the beach. One notable exception (and there are others) is Eld inlet where they seem to set all over the place. It sounds like you are seeing a set below +2 so you may want to move them to an even lower level, or just try to avoid the setting window. If you already have lots of barnacle on your gear, this will restrict water flow through the bags and you oysters will grow a lot slower. I would also recommend getting another set of bags and purses and swapping them out each year (if you have them in the water during the barnacle window). It you leave the barnacle covered ones up on shore for a few months they will be easy to clean off for next year. Now that you have a set on you oysters, all you can really do is clean them off by hand. I use an oyster knife and a brush. The good news is that there will not be another set until next April.
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I hope this helps. As you can tell, oyster gardening is an art more than a science and every beach is unique, which is what makes shellfish gardening so much fun!

I've found that I can reduce the barnacle set by not cleaning off the oysters/grow bags and letting some sediment settle on them during the spring barnacle set. I don't have much wave action on one part of my beach so it is fairly muddy and silting up can be a problem. But during the spring I intentionally let things go without cleaning for a while. Barnacles set best on clean surfaces/shells. The Olympias in particular seem to do fine wth a little mud in the grow bag. Kumomotos also don't seem to mind the mud as much.

The regular Pacifics tend to get burried if I don't turn the bags over regularly, so I'm moving my Pacifics off the substrate and onto a rack system. That way all of my oysters can grow over on the more muddy part of my beach, and I can focus on steamers where the beach is more firm and gravelly. With racks I had minimal mortality and there still seems to be enough fine sediment settling on the shells to keep the barnacle numbers down.

Nice post Milt! I had not thought of this, but it makes good sense. It would be great to see photos of your shellfish garden.

Barnacles are the annoying part of farming oysters. We also use the aqua purses which does cut down on barnacle growth, but we are also pressure washing our bins on a regular basis to inhibit growth. About once a year during the extreme low tide week in June or July when we do our big farm clean-out, we use short pry bars that are used to remove trim to knock of any barnacles that got through. Thankfully because of the pressure washing, it isn't too bad. We have over 50 bins and my husband and I can go through all of the bins (sorting by breed, sorting out mussels, etc) in a week on the beach just when the tide is out.