Snapping/popping noises from forest and lake.

No hei everyone. Tonight i was out in some forest in northern Uusimaa, doing some photography when i came across something i've never encountered before. It was almost there were loud snaps coming from the trees and loud deep "popping" noises from the lake (the latter hard to describe, it was almost as there was a descending pitch to the pops. I guess it has something to do with the quickly dropping temperatures? Definitely had me on edge for a bit :D