I started working on emptying my compost box today, but had to stop after 10 minutes. I discovered a nest of bumblebees. I hadn't even noticed the nest when I started working. All of a sudden, the compost box was surrounded by bees. After several minutes, I noticed the bees were starting to hover around one particular area. I slowly walked over and found a series of yellow "eggs".

The first set of pictures were taken 15 minutes later. There are less bees around at this point in time. I'm hoping they soon move to a new area to rebuild the nest.