I've also seen males on these same shrubs. The hummingbirds in general have been one of the most common birds I've seen along the Tuolumne Parkway Trail over the last few days. Some of the shrubs are flowering despite the dry conditions, providing a food source. There have been quite a few bugs flying in the air, and hummingbirds aren't at all averse to consuming bugs. They need the protein. They need the sugar too, given that their metabolism is such that they could starve in the space of a few hours or a day.