This waterproof casing has been specifically developed for the AudioMoth as a part of a research project on the passive acoustic monitoring of bird species in forest ecosystems.

It was designed to shield the autonomous recording unit from environmental elements and to simplify attachment to trees using a strap. In contrast to the official injection molded case, this casing can be secured to a tree with a wire loop and a small padlock as a precautionary measure against theft and potential data loss. When secured to a tree, the lid is locked as well and can not be opened. (The material will of course break when enough force is applied)

Durability and user-friendliness have been field-tested by the Wildlife Institute of the Forest Research Institute Baden-Württemberg, Germany, over a four-year period. Throughout this time, the case was utilized in 196 recorder deployments in temperate forests in Southern Germany, amounting to a total duration of 7300 field days. The cases used during field-testing were printed using UV-resistant ASA (100μm, 20% infill).

Water resistance (tested with a submersion test) can be achieved by carefully assembling the casing and utilizing an appropriate seal along with a waterproof cover for the microphone opening (see additional material required below). While primarily designed for mounting to a tree trunk using a strap, additional holes on the case's back permit the use of zip-ties, string, or wire for diverse attachment methods. The version that can be downloaded here comes without the "FVA" logo.

** Additional materials required **

• Sound-permeable waterproof fabric to cover the microphone opening (available at akustikstoff and other potential suppliers)
• Lid seal: A silicone seal (30 +/-5 Shore A) with a 1 mm thickness was found effective
• Metal rod: 2.9 mm diameter for the lid hinges and closing mechanism
• Adhesive: Necessary for securing the metal rods in place

** Field use recommendations **

• Attachment loops on the case's back accommodate straps up to 25mm wide
• A lock similar in dimensions to the ABUS Titalium 64/TI/25 works best for securing both case and lid