Nestled in the iris

About a week ago, I was walking in the coastal prairie during a chilly afternoon.  I noticed a bumblebee nestled in an iris flower, then another bumblebee in a different iris, then two bumblebees in a third iris, and there were quite a few others.  I'm not sure why so many bumblebees ended up in Douglas Iris (Iris douglasiana) flowers, but it was a nice setting: