[NHCOLL-L:4540] RE: Question about Wet Collection

[Thomas Labedz]

Ashley

If the collections are as neglected as you suggest the best approach might
be to start over again.  New jars, new closures, maybe new labels, new
fluids of proper concentration, proper documentation of the process, and
implementation of procedures to prevent this situation again.  An exception
would be if any of these specimens are of high scientific value where such
changes might affect their usefulness in research (e.g., a type specimen).

Are you certain all are alcohol, some might be formalin?  What type of
alcohol?  Lots of possibilities.  

Some of those specimens that have greatly reduced volumes of fluid may need
more work than just adding fresh alcohol of the proper concentration.  Those
may be evaporated down to being mostly water.  On occasion when I've had
incoming specimens from older collection in that condition I've re-fixed
them in 10% neutral-buffered formalin as a precaution, and stepped them up
from that to 70% EtOH.  Maybe that was too much but I then knew what was I
was dealing with.  The old fluid was shipped off to HazMat.  

Yes, 1000 jars might take some time.  I'm in the final stages of
standardizing jars and closures for our fish and herp collections, totaling
25-30,000 jars.  I've been at it for over well over 5 years with student and
volunteer help.  But the rewards in knowing what we've got and how it is
maintained makes it worth it.

Thomas E. Labedz, Collections Manager
Division of Zoology and Division of Botany
University of Nebraska State Museum
W-436 Nebraska Hall
900 N. 16th St.
Lincoln, NE  68588-0514
402/472-8366   fax 402/472-8949
tlabedz1 at unl.edu   www.museum.unl.edu


-----Original Message-----
From: owner-nhcoll-l at lists.yale.edu [mailto:owner-nhcoll-l at lists.yale.edu]
On Behalf Of Ashley Henderson
Sent: Wednesday, September 23, 2009 12:58 PM
To: NHCOLL-L at lists.yale.edu
Subject: [NHCOLL-L:4538] Question about Wet Collection

Hi Everyone,

I am looking for some advice about wet specimens.  I recently became
the Collection Manager at a museum with around 1,000 wet specimens.  My
experience with them is very limited.  I have read many articles
regarding their preservation, but I still have some how-to questions and
am seeking some advice.  The wet collection is mostly herpetology and
marine biology with some entomology.  They are in glass jars ranging in
size from a half gallon to small vials.  Most jars have plastic Bakelite
lids, which I have read allow for a great amount of evaporation.  Some
of the specimens are 30 to 40 years old and have been topped off
countless times.  Some of the jars have not been topped off recently and
are half empty.  So, I am dealing with a wet collection for which I have
no idea what the ethanol concentration is from jar to jar.  I would like
to work through the collection and bring each up to 70% ethanol.  From
my research, I understand that it is best to avoid completely changing
out the preservative.  What is the best way to test the preservative in
the jars so that I can then add the appropriate amount of ethanol to
establish a  70% level?  I have researched using hydrometers.  However,
many of the specimens in small jars do not have enough preservative to
remove a sample for testing.  What other methods are there and what
would be the best process for testing each of the specimens?  Or is it
even necessary?  Any advice would be greatly appreciated.

Thanks,



Ashley Henderson

Collection Manager
Corpus Christi Museum of Science and History
www.ccmuseum.com
(361) 826-4659