Friday, March 25, 2016

Hey! I found an oyster. Can I eat it? NO!

Increasingly we are hearing from people who find a random oyster as they are walking the shore. They send us photos and it is interesting to hear about their comeback. One question we get is “Can I eat it?”

Eastern Oyster Photo Crassostrea virginica
Eastern Oyster Crassostrea Virginica

The answer is “No. Do not eat oysters you find at the shore. Here is why.  The oysters that you get in a store or restaurant have been carefully harvested from waters that are known to be clean and healthy.  Those harvested oysters are handled carefully with well-documented processes that track their source, temperature and movement.  Even with these quality control procedures, on rare occasions a person or two can get sick.  A random oyster found on the shore has none of these mechanisms to ensure it is safe to eat.   Even waters that appear safe may be affected by storm run-off, point source pollution, or even an undocumented combined sewer overflow. 

So Just leave the oyster as you found it so it can grow and do its job filtering the water.

There are some things, you can tell about the found oyster if you examine it closely.  For example, if  it is attached to a rock like the one below, it has set in this spot as an infant. That means that somewhere within a mile or two there are reproducing oysters who begat it.  You also may be able to tell its age, by looking at major rings.  A typical Massachusetts Oyster can reach 1-2 inches in its first year. And around 3 inches the second in optimum conditions. 
Eastern Oyster Photo Crassostrea virginica set on stone
Photo of an oyster that has set on a rock through natural reproduction. This one is a year old.

Based upon some discussions with Steve Patterson of RogerWilliams University, and some amazing shell samples he shared an oyster will max out in size around 10-12 inches in length. They can survive for 30-40 years.  The reality is that they rarely get this chance because they are so darn good to eat and man is extremely adept at hunting out protein that cannot run.  BTW- if you are looking for a great speaker Steve is wonderfully engaging and fascinating to listen to. He has done amazing things with the oyster gardening program in Rhode Island.

If it is Summer time you may see a thin edge that looks like fingernail. That edge material is fresh shell that the oyster is laying down as it grows. 

If you see black and white stripes radiating outward from the hinge, it may be a descendent from a line bred for aquaculture.

You also may come upon a European Oyster  (Ostrea Edulis) or Belons. They have a  rounder or more scalloped shape. They were introduced to the Massachusetts area by accident and can be found as far South as Plymouth and as far North as Maine.  They can grow in deeper waters than our native Easter Oysters.

European Oyster Photo Ostrea Eulis  Belon  Ernest Hemingway's favorite
European Oyster Ostrea Edulis
But remember, oysters from stores are for eating. Oysters on the shore are for leaving. The only time you should be harvesting your own oysters is if your town has a documented program with designated areas and limits. If you go it alone you may be jeopardizing your own health or that of a loved one.

Tuesday, March 22, 2016

NH Oyster Job

Fat Dog Shellfish Co., a rapidly growing oyster farm in New Hampshire's Great Bay, is seeking a full time Farm Manager.  For a complete job description, please email Jay at
New Hampshire's Great Bay is an amazing inland waterbody that once supported a heavy oyster population. UNH's Ray Grizzle has been working to restore the important keystone species and one of our volunteer intern alumnae was part of the effort.