>From: Bert Bartleson <[log in to unmask]> >Reply-To: Conchologists List <[log in to unmask]> >To: [log in to unmask] >Subject: Re: pegging clams--how to >Date: Tue, 25 Jan 2005 15:38:53 -0800 > >Hi Joan, I just got out my old college text “Biological Techniques – >Collecting, Preserving and Illustrating Plants and Animals” and read the >chapter on Mollusks.  The author, Jens Knudsen, tried many different >techniques to kill and relax mollusks but all varied in their success. > >Here are some of the methods mentioned:  1). Marine clams may be killed by >soaking in fresh water (you tried this method without success); 2). Place >bivalves in habitat water until they open up (they suffocate or die of the >heat); 3). Heat-kill method -- hot water, boiling water, microwaving; 4). >Freeze-kill method; 5) various necrotizing agents added to the water -Epson >salts (You tried this), alcohol (you tried this), menthol, benzocain, etc. > >After the kill step the author suggests putting a wooden peg (3/16th inch in >diameter) between the shells and then sequentially preserving in 35%, then >50% and lastly 75% alcohol.  Formalin at 5% and then 10% can also be used >but not much of this chemical is used any more. > >My suggestion is to give them some hot water and see if that does the trick. >I had some obstinate oyster shells that I both planned to eat and keep the >shells from and I used the microwave at 5-10 second intervals and it did the >trick.  The only problem with this method is its trial and error.  Too much >time and you can blow up the shell or the animal and make a terrible mess. >I've heard of people having to buy a new microwave oven when they tried this >method with a dead shellfish. > >Clams are "tough guys"; maybe they just need a bit more time.  You will get >them eventually.  Bert Bartleson in foggy Olympia, WA >________________________________________ >From: Conchologists List [mailto:[log in to unmask]] On Behalf Of >[log in to unmask] >Sent: Tuesday, January 25, 2005 10:47 AM >To: [log in to unmask] >Subject: pegging clams--how to > >Conch-L subscribers: >For a presentation to a 7th grade class, I had the idea to procure >demonstration specimens from my local seafood market.  They had >"littlenecks" and "cherrystones" from Virginia.  I wanted them relaxed, with >foot extended, before preserving them.  Being a novice to narcotization of >marine bivalves, I consulted various references but have yet to find a >methodology to get them to relax.  They have been in freshwater with some >ethanol added for 24 hrs.  Four hrs ago, I took one of those and put it in a >separate container, saturating the freshwater+ethanol with epsom salts, and >placed this container on my office heat register which I have turned up to >at least the high 70s.  Still closed up tight. >Any advice greatly appreciated. >Joan Jass >Milwaukee Public Museum >Email [log in to unmask] > >---------------------------------------------------------------------- >[log in to unmask] - a forum for informal discussions on molluscs >To leave this list, click on the following web link: >http://listserv.uga.edu/cgi-bin/wa?SUBED1=conch-l&A=1 >Type your email address and name in the appropriate box and >click leave the list. >----------------------------------------------------------------------