Last night MFO and I attended another in the series of PEM (I
think Paleontology, Ecology, Marine) lectures at our Calvert Marine Museum on
the Solomons. Once again it concerned
our little friend the Oyster which has led me on a chase lately. It was given by Dr. Ken Paynter, Director of
the University of Maryland College Park's graduate program in Marine,
Estuarine, Environmental Science (MEES) program. He is also the Director of the Paynter OysterLab. His subject was: “Restoring Oysters to the Chesapeake Bay”. Although this is a pretty popular and
socially hot topic these days, we found it to be a very informative presentation. Not just a bunch of platitudes,
condemnations, and touchy feely wishes, his presentation contained a lot of actual
data including statistics, things like distribution maps, density numbers and
other things that engineers appreciate. We
heard about diseases like MSX and Dermo (Protozoan Parasites) and their effects
on the oyster population (not so much in areas/periods of low salinity); showed us some underwater video of a reef that
has silted over, and some footage (is that still a word?) of a restored
reef. He was very strong in his opinion
that reefs were the key to restoration of the oyster population in the bay. They not only produce a nice home for Ollie
Oyster and family, but also provide environment for benthic animals such as mud
crabs, Gobi’s and so forth. Of course
there were charts with arrows and bubbles illustrating the life cycle of a
healthy oyster reef. His message was
fairly positive, but not overly optimistic.
He talked about threats of nitrogen, run off from development, the usual
stuff. Also had numbers that supported
the usual statistic of a healthy oyster reef can filter: 1.4 million gallons of water PER HOUR, per acre:.. Just imagine.
Busy little creatures.
Although he didn’t talk about aquaculture much, preferring
to consider the bay in general, there were (what I assumed were) several oyster “farmers” in
the audience. The question and answer
period that followed his talk had some pretty interesting discussions. Ken was more interested in a healthy
bay/oyster environment than farming for market use. Speaking of aquaculturists,
the “Shore Thing Shellfish” folks from Tall Timbers were in the lobby before
the talk and were shucking some of their farm raised oysters. Other “farmers” had literature available
(Hollywood Oyster Co., Patuxent Seafood (Broome’s Island)). There is also an organization called “TheSouthern Maryland Oyster Cultivation Society” which I had never heard of, they
seem to be primarily an advocacy society.
Anyway, the shucked Oysters were plump and very good.. Since we didn’t have dinner before the
lecture I tried to be courteous, but darn it, somebody had to eat them!! There was also some wine from a local winery
for tasting or purchase. A nice little
event. Just another nothing to do event
in Southern Maryland. I was encouraged
by the enthusiasm shown both by Dr. Paynter and the members of the
audience. Maybe there is some hope…
Culinary Thoughts
You all know about the conundrum: “don’t eat oysters in
months with no “R” in it”, April
still qualifies, but May is next and you will still see Oysters on the menu… why is
that Mr. Bottom Feeder? Well, I decided
to look into that.. First a little
summary of the life of a native Oyster (with help from “Sex, Death, and Oysters”
by Robb Walsh). Of course, it is all
about reproduction which, when you think about it, is why we are all here…At
the end of the summer, when water temperatures begin to cool, the oysters begin
storing a carbohydrate compound called glycogen, which to humans tastes sweet,
like sugar. As the water gets colder and
colder, they store more and more, thus getting plumper and taste (to us) really
good. They stay that would throughout
the “R” months. Then, when the water
starts to warm up (around now) the little guys (or gals, a difficult call)
convert the glycogen to reproductive material.
At this time they lose their “sweetness” and take on what some people
call a “fishy” flavor. Then, when the
spawning begins, millions of larvae are formed and those that survive predators
fall to the bottom hopefully finding a home (reef) to begin growing. In summer, after spawning (hard work!) the
oyster has lost much of its body weight and almost all of their flavor. A term I’ve
heard of is “Spawny”. Also summer is the time of year when those little
diseases are most active. So, yes, DON”T
eat a wild oyster (from the bay) during all this time until the cycle starts
again in the fall.
So why do we still see oysters on menus in "no R” months? Well, it gets a bit more interesting and we
have to get into the genetics of the oyster.
How can a simple little thing get so complicated? Well, native oysters are “diploid”, meaning
that they have two sets of chromosomes with the egg and sperm contributing
equally. The two chromosomes combine to
form another diploid oyster which go through the cycle described above. But now enter the “Triploid” oyster which are
produced at spawning by a process which causes the egg to contribute two sets
of chromosomes and the sperm one set, resulting in what is called a Triploid oyster. Without getting too deep in the process (which I wouldn’t
understand anyway), the bottom line is that Triploid oysters are essentially sterile
and therefore don’t go through the reproductive cycle like the diploid and so maintain their meat
quality because they do not become “spawny”.
That means that they will remain fat and tasty all year. While Triploids do occur in nature, they are
minute compared to diplods. So, many
commercial seafood companies pride themselves on production and raising Triploid
oysters. In addition to remaining
edible, the Triploid oysters grow faster, a key factor for aquaculturists, who
after all are in it to make a profit.
So here you are in your favorite seafood restaurant in July,
and you see “Oysters on the Half Shell” on the menu. You’re tempted, but what should you do? You could ask your server “where do these
oysters come from”? Hopefully the
answer will be “from so and so oyster farm”, and let your eye tell you if they
are diploid or triploid – although
hopefully the server knows. But, if the
answer is “Blue Point” or some other answer there is another avenue. Each bag of oysters is required to have a tag
attached that specifies the origin, the harvest date and location, and type. I looked at one that came with the Shore Thing
samples and it contained all the information. If you ask to see it in a
restaurant, they are required to show it to you. Yes, a bit complicated but is some assurance
of a quality product.
So it’s no wonder that the simple little oyster remains a
thing of wonder and mystery.. As Jonathan Swift mused: “He was a bold man who first ate an oyster”..
and I bet he was
DFD
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