Wow, that's probably the angriest chickadee I've seen and heard! I couldn't tell if the bee was killed or chased off - the buzzing just stopped. Imagine a huge fanged insect invading your house and nursery, no wonder the bird was upset.

Claire

That is an impressive video! So has the chickadee managed to permanently evict the bee? Poor bird sounds very distressed and upset in the last frames. (I don't imagine you could capture the bumblebee in a jar and transport it 20 or 30 miles away for release?)

I caught this by random. I just happened to turn on the recording in the middle of the first encounter and left it on for 5 hours by accident and found the second battle where you can hear the bee flying in. The next day a chickadee stayed on a branch of a golden delicious apple tree right next to the box and was very vocal and I saw another bee try to get into the box and the chickadee attacked it. It happened so fast I could not tell if the bee was repelled or got in. I risked opening the box real quick to see if I could kill the bee but did not see anything. That night the chickadee slept in the nest and is also in the nest tonight Monday 18th. I don't know if the bee finally gave up or was killed.