Moths made a “frass” of this mask

Object of the Month: 10/2017

What is it?:

Nunamiut Eskimo maskDamaged mask
Damaged maskCourtesy SMM


Origin:

Alaska


Age: Made ca. 1970
What is it made of?:

Caribou rawhide, with caribou hair and wolf skin


Accession #: A77:4:1

This Nanamiut Eskimo mask looks to be in pretty good shape. It wasn’t always the case. When taken off exhibit in 1994, it was documented in good condition. But a check on it ten years later showed clothes moth frass.

What’s frass? Bluntly, it’s the remains of insect debris like larva skins, eggs and excrement.

How was it treated? First the mask wrapped in plastic and frozen for two weeks to kill any remaining living moths. With consultation from the curator and conservator, the best course of action was determined to be removal of all of the loose hair and fur, along with all insect frass.

Frassy: The disheveled mask was in need of makeover when it was checked on in 2004. Clothes moths had left their mark. You can see it looking a lot better today in the case to the left.
Frassy: The disheveled mask was in need of makeover when it was checked on in 2004. Clothes moths had left their mark. You can see it looking a lot better today in the case to the left.Courtesy SMM
All of the removed material was saved for future study or use. If we decided to restore the object to it's original appearance, we would find a source of similar wolf skin and use reversible adhesives to adhere it to the bare areas. You can see the dramatic result of that cleaning in the photographs. Clothes moth larva typically graze along the skin, eating the base of the hair and fur. It can take a while to notice the infestation because the hair and fur looks intact from the top. In serious infestations, such as this one, the moth larva will even eat through the skin, as you can see around the mouth.

Checking objects stored near the mask confirmed that the moths hadn’t spread to them.

Damage like this to an object in storage is rare. We practice Integrated Pest Management. We carefully inspect, isolate and freeze any new items added to the collection. We regularly monitor the entire museum for insect activity. We practice good housekeeping techniques to prevent crowded or dirty conditions that would allow infestations to thrive. The objects stored near the mask were carefully inspected and monitored for infestation after this was discovered. We didn't find any other evidence. How this was infested and nothing else near it was, and when it happened remains a mystery.