Yesterday as I worked in my garden near a birdhouse that is home to Bumble bees for the second year in a row. I noted two odd events that I hope someone can explain. The birdhouse sits on a bench next to my front door and gets sun from about 9 AM to 1 PM. It is made of barn wood has two holes and is purely decorative. The roof is corrugated tin and is not attached securely but provides rain cover and ventilation along much of the pitch.

First question: I noted BB's taking turns sitting in the opening and fanning their wings. Is the 'nest' over heated? Is there anything I can do to help them?

Second question: I witnessed a BB fly from the house with a very heavy load and fall directly to the cement walk. It struggled mightily to fly but barely made ground clearance. It seemed to be carrying what looked like a larvae. It was whitish, about 1/4 inch, and maybe moved on it's own. Before I could get a close look, it dragged itself into foliage and I could not find it. What in the world was it carrying? Was it removing a pest? Was it starting a new nest? And perhaps another clue; I noted a few flies buzzing and landing on the birdhouse. They had a metallic sheen. Any correlation?

Hoping someone can answer my Q's, Kimmers