I have over 100 audiomoths deployed around southern Lake Superior (MI, WI, MN USA) currently sampling fall migratory songbird activity. They have energizer lithium batteries, 64gb sandisk extreme SD cards, and are in the IPX7 waterproof case zip tied to trees above the snowpack line. I had planned to return to collect all of them in November, and then redeploy them in the same sites next March/April.

My question is what if I just left them up all winter to save money on travel this fall. I'm sure they will deplete batteries and or fill SD cards by December, so they would just be sitting there in the case dead through the winter. And then I would not return to them until early spring to swap cards, batteries and reprogram for spring migration sampling.

Is this worth the risk of data or device loss? How well do they hold up through months of snow, extreme cold, and temperature swings? I'm asking about both the devices AND the SD cards.

Thanks for reading!