I opened my wooden storage shed last night and based on the smell, I'm thinking something died either in it or under it. The odor isn't overpowering, but there's no doubt that it's there.
If the creatures final resting place is under the shed, it's staying there, if it's in the shed, I'd have to empty the shed to fiind it.
How long before it goes away if I do nothing?
Most of the items in the shed are "hard" so I doubt they would absorb the odor, but there are some soft items like life jackets, folding camp chairs, a canvas bag for my cargo carrier, etc.
I'd leave the doors open to air it out, but that's probably how the creature got in there in the first place. I noticed some damage to the plywood floor right where the 2 doors meet when closed, so I'm assuming the creature got in when the doors were opened and tried to get out through the only opening it could see. When it couldn't, I think it must have crawled into a back corner and died.