A Sad Tail

Last week we celebrated the return of our beloved Nile crocodile skeleton. It’s been out on loan to the Oxford University Zoology Department during our closure year, but is now back in position in the Museum gallery for all to see.

To mark the occasion, the conservation team decided to give the crocodile some much needed care. Originally this piece was displayed on carpet tiles, which can be potentially harmful to the specimen as they deteriorate… as well as looking pretty ugly! My first step was to remove these from the base of the specimen. I was then able to assess the skeleton for priority areas.

Originally the specimen was articulated (held together) using a combination of iron and copper wire. This skeleton is over 150 years old and, during its time on display, these wires have corroded and stained the bone; this was particularly prominent in areas of existing cartilage, such as around its ribs. So I removed the old wire and replaced it with stainless steel, which has a longer life span.

The existing articulation had also failed in some areas; this was most obvious on the tail, which had lost its natural curve and gained a limp collapse – lovingly referred to by visitors as a ‘sad tail’. A ‘happier tail’ was obtained by threading a stainless steel wire through the vertebral column, meaning no new holes would need to be drilled.

The alignment of the rear of the skull and the atlas and axis bones at the top of the spine were not correct. To treat this, I removed the skull, allowing access for wire replacement. The skull was returned to its original supporting armature, now with conservation grade cushioning to relieve any unnecessary pressure on the bone. I guided the skull into its new position and fastened it in place.

Once complete, I coated the base of the specimen with sand (a more natural environment for a crocodile than carpet!) and called in some strong helpers to replace the heavy glass lid.

This project was particularly exciting to work on as it offered an opportunity to discuss the work of the conservation department with the passing museum visitors. I was able to make a few school trips a little more exciting with the phrase “Would you like to hold a croc skull?”.

Nicola Crompton, Conservation Intern