Standard Measurement for Clams?

[npaden]

Well, I just got in some clams from an unnamed vendor, and while they were pretty (you look at the pic and get the ones you want) I was somewhat disappointed in the sizes.

I have always thought that you measure a clam in a straight line from tip to tip. When I talked with them they told me up front before I ordered that they measure theirs over the curve of the shell. I didn't realize that it would make that much difference, but on a squasmosa that I got it made at least a full inch difference. I ordered it as 5"+ and it is 4" on a straight line at the very most.

On the smaller maximas this didn't make that much differrence - a 3.5" might have been 3", and on the ones < 2" it hardly matters.

I was just wondering if there is some kind of standard or if we need to inquire with each vendor before you order how they measure their clams.

If I measured my clams like they measure theirs I would have some big clams as my derasa is at least double the size of the 5" squasmosa that I got!

Thanks, Nathan

 

[toptank]

Nathan,

I was always tought to messure from end to end as you stated, not over the base of the clam. If that was the case my 8" derasa would be approx. 13"

Sorry to hear that happened to you.

Barry

 

[npaden]

Yeah,

The vendor told me up front that they measured that way, I just didn't realize it would make that much of a difference.

I talked with a few other people as well and I know ORA measures their clams from end to end using a caliper excluding any odd scutes that would be protruding.

It really makes quite a difference like you said. I think my 8" derasa would be over 12" measuring around the curve!

I'll take some pics tomorrow. They are pretty clams, just a bit smaller than I was expecting.

Really it makes the most difference on the squasmosas and derasas I think. This also made me realize that my clams I already have, have grown quite a bit since I ordered them. My Croceas that I bought in the 2 to 3 inch range are now at least 4" and even my little Maxima I bought at around 2" a year or so ago is closer to 4" than 3" now. I'll have to get a plastic ruler to take home and do some measuring!

FWIW, Nathan

 

[jim norris]

Nathan,
I with toptank I try to measure clams in a straight line end to end. Now on the really BIG ones I measure by pounds!!!
Jim

 

[toptank]

Jim, I got a 4 lb derasa. Where do you want it shipped?

 

[jim norris]

Toptank,
It maybe more cost affective for me to come to SD!
jim:spin1: :spin1:

 

[danield]

I searched, and tried to find a old thread (I thought it was on rc) that was a discussion on clam measurement, I thought it was back 5 or 6 years ago.

ANYWAY,..I have searched and find information (US Goverment on the take of clams in the somas, biological research on growth, ect) that the measurement of a clam is, shell length (SL) tip to tip thats the standard.

The thread I was looking was a discussion of measuring along the Arc of the shell opening to determaine the clam length, maybe at one time a STANDARD in the reef keeping industry.

What method is currently the "Accepted industry standard", on clam size measurement??

One discussion I recently reviewed on clams I believe,... may have been refering to the length of a clam when the clam was open and may have included the extended mantle?

Now all that being said if I were selling clams on the internet, and the accepted standard was Shell Length. Would it NOT be inproper, for me to list a clam as a length lets say 4" to sell it.

The purchasing party recieves the product and the SL is 2 1/2" tip to tip streight line (goverment method), and 2 3/4 tip to tip following the arc (Old reef industry standard)

When the seller is questioned the answer is a partial statement, and question, "Ok your clam was at least 3" and it's not 4" open?"

This implies he's measuring the extended mantle does it NOT ??

To further support this thesis another person questions the same party, ie, "Item not as described; barely 3"; barely alive;"

To this the seller replies, "Using eggcrate as scale it is at least 4"

What kind of answer is that?

Use a tape measure, a guage, or a caliper and measure the SL (shell length) the "accepet standard" for measuring the item you are refering to, and inform yourself of accepted standards of the industry you are working in, or else suffer the conquecenses of people making asumptions, and labeling you a lier, cheat, thief, and on top of all trying to use deceptive practices to promote the sell and profit of products that are NOT quite what you are representing them to be.

So Guys and Gals what is the current "accepted standard" for clam size measurement??

 

[wjgeese]

Measuring a clam over the curve does not accurately represent the length of the clam...it overestimates it. Sellers who do this know exactly what they are doing; they are trying to get more out of what they have. Pretty slimy in my opinion.

 

[rwbogard]

Any scientist will tell you that the only way to get accurate and precise measurements is using a caliper. Trying to bend a piece of string or measuring tape around the curve is just plain ridiculous. Lookup any studies on oysters or clams and they all use calipers to measure.

 

[danield]

Ok,...ok,..I stand corrected, I had previously stated the size of this Crocea 4" clam as acutally being 2 1/2" in size.

The seller on the other hand stated, "Ok your clam was at least 3" and it's not 4" open?"

rwbogard 's post:
"Any scientist will tell you that the only way to get accurate and precise measurements is using a caliper. Trying to bend a piece of string or measuring tape around the curve is just plain ridiculous. Lookup any studies on oysters or clams and they all use calipers to measure."

Made me think about one of my other hobies,...wood butcher (Furniture design and building) and sent me to my wood shop to get the 6" digital caliper that I use on precision work, like motrice and tennon, inlays and the such.

As you can see by the picture the clam is 2.4375 " in length, and that is being generous as I incluted the sculte on the left side.

Peace out
Danny
The old guy

 

[scapes]

looks like you might be right!!