We bought the mask during a trip to the Chiquitanía region of Bolivia in 2002 while I was posted there. The Chiquitanía is a beautiful part of Bolivia where six churches (San Francisco Javier, Concepción, Santa Ana, San Miguel, San Rafael y San José) built by Jesuit and Franciscan missions in the 18th century have been restored and selected in 1990 as UNESCO World Heritage Sites under the name Jesuit Missions of the Chiquitos.
The mask is used for to the dance of the “macheteros” (machete bearers), a local dance typical of the Beni region of Bolivia and it was acquired because of the insistence of our son.

Our young daughter posing as a “machetera” wearing her brother’s mask.
After the trip the mask was quickly forgotten joining the vast amount of jumble that we have accumulated over the many traveling years. Eventually the mask ended up hanging in the back verandah of our farm in Salta where it is to be found today. But not for long…
Noticing that the bat droppings extended beyond the two bat nests my daughter (a bat fan!) and I placed outside the house (see: https://bushsnob.com/2017/04/02/homely-bats/) Mabel checked the mask and, through its mouth, she spotted some fur and requested that I carried out a thorough inspection of the inside as a bat was surely living there!
I did check and found a bat trio sheltering happily in the mask, cozy and away from the rain!

The bat trio in detail.
Although I am trying to defend them, it seems likely that both mask and occupants may need to move away from the verandah to a more ventilated area where their droppings and other odours would not interfere with our lives.