Manta ray wing

Sarah-Jane Rennie asked about how to deal with odorous Manta Ray
specimens.  I actually did have experience with odor removal from a
set of sting ray jaws.  Solvent soaking had no effect on removing
the oily compounds that were responsible for the rancid odor.  I
placed the jaws in a Labconco vacuum chamber with a tray of zeolites
at the bottom.  It took approximately 2 months for the majority of
the smell (a non-instrumental, empirical observation only) to be
reduced to where the jaws could be handled without an overt gastric
reaction.

The wing section might be too large to fit into the typical lab-size
vacuum chamber.  You might have to fabricate a custom chamber. The
zeolites will adsorb the molecules responsible for the odor, but I
think given your short time frame, it would be more effective in a
vacuum.

For the fleshy tail section, could you slit the tail and remove the
remaining flesh and restuff the skin?  If not, you might want to
consider freeze-drying that specimen, and possibly the wing section
as well.  There is a Minneapolis company, Freezedry Specialties,
Inc., that has developed a specialized taxidermic freeze-dryer that
might be applicable to this type of problem.  Check out their web
site at <URL:http://www.freezedry.com>.

If you start soon with treatment, you might be able to prepare the
objects for exhibit by November.  You might also want to design
well-sealed display cases with accessible trays of zeolites in the
bottom for odor adsorption and control.  Let me know if you have any
other questions on this.

Paul S. Storch
Objects Conservator
John and Martha Daniels Objects Conservation Laboratory (JMD-OCL)
B-109.1, Minnesota History Center
345 Kellogg Blvd West
St. Paul, MN  55102-1906
651-297-5774
Fax: 651-297-2967

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                  Conservation DistList Instance 12:21
                 Distributed: Thursday, August 27, 1998
                       Message Id: cdl-12-21-003
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