One of the longest experiments I have done recently was recording the decomposition and predation of a fresh dead roe deer. I began it back at the start of December, then moved my trail camera away at the end of spring. In between, I recorded hours and hours of videos of what happened to the body as it was left in the wood. For the first month, the answer was not very much - but the next two months made up for that !
One warning at the start: I know a lot of children read this blog, so be prepared that this post shows a lot of images of decomposition. None of them are too bad (well, one is a bit), but just be warned before you click on any videos...