Written by Jen Gossman, MSc first year Conservation Practice student at Cardiff University.
I received a mounted taxidermy otter in still life pose without a base from the Tenby museum, Wales where it had been in long term storage wrapped in Tyvek. On initial examination it showed some skin shrinkage and was covered in a thick layer of dirt, grease and dust.
The main concern was an infestation by carpet beetles. Inspection of the fur and hide revealed evidence of the beetles in the form of fras, some dead or empty larvae casts and matted fur alongside large bald areas.
The decision was taken to send the otter to be frozen using industrial freezers with the valued assistance of Julian Carter from Amgueddfa Cymru (Cardiff), where it spent 3 weeks at -30 degrees wrapped in plastic sheeting and placed in a strong container to avoid freezer burn or contact with moisture. Once the otter returned, a detailed examination of the mount could be undertaken.
The exact age of the mount could not be determined due to the lack of records but the potential of there being arsenic contamination, commonly used as preparation and an anti-pest measure prior to the 1980s, was likely.
In response to this I decided to examine the mount with surfaces covered using polyethylene sheeting and a fume cupboard, making sure to wear protective PPE whilst handling. For certainty and the safety of students and staff, we decided to undertake tests to ascertain the likely presence and potential contamination level of the mount by arsenic. I used the XRF machine and dab tests to sample common aggregation areas such as the feet, armpits and ear areas. Two tests were decided on to allow a holistic view of the mount.
Alongside the general dirt levels and grease or debris on the surface layers of fur, underneath this and close to the hide, was found to have been warped by the potential actions of moisture or eaten and matted by pest action. The fur itself was severely degraded from fading and showed some embrittlement from this occurrence. There were various areas of the hide that had been subject to warping. This had potentially caused dislocation of the toes and warping of the jaw. It was decided not to address this as it had low impact on the mount at this time.
Due to Covid-19, the actual treatment of the mount has sadly been put on hold but the planned treatment is to clean and remove pest damage and dirt from the fur and attempt to recolour the mount to reflect a realistic appearance. I decided that recolouring was important as I feel that the purpose of a taxidermy mount of this type, is to represent as much as possible the real animal. Taxidermy either scientific or trophy most commonly has the purpose of allowing a closer understanding of nature, and may provide scientific value. To maintain the validity of that experience the accurate appearance of the mount is important to our understanding. Re-colouring may hide history of the mount and will interfere with any scientific data but will enhance public experience, I feel that this opinion is important to consider when displaying taxidermy of extinct species.
The treatment of the pest damage on fur layers will be performed by delicate detangling and very light brushing of the hide with tweezers, pick and a soft brush. Matted fur being gentle tweezed apart followed by a soft brush and a filtered vacuum to pick up loose material.
Grease and ground in dirt will be removed with a mixture of 1:1 ethanol and deionised water. The solvent will allow the removal of the dirt and will retard the exposure of the mount to moisture from the deionised water which itself will reduce the excessive drying of the fur which could lead to embrittlement. A blotting paper guard will be used to prevent the solution from touching the hide directly. The solution is applied with a swab, working backwards through the fur in thin sections which are then brushed back to a life-like appearance. Once free of grease, dirt and pest debris, colouring can be performed.
The exact decision to proceed with this is the responsibility of the client museum but the process proposed will be to use a mixture of acrylic dyes and ethanol. These will be applied in very thin amounts via the controlled use of air spray methods applying thin coats working systematically over the hide using realistic colour pallets of brown auburn and umber tones to achieve a representative coat.
The mount is now snuggled up in our stores awaiting the return of the students and the commencement of the treatments.
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Hi Jen,
Did you get an arsenic result before suspending operations?
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