Fall colors

The large-scale movement of California Tortoiseshells (Nymphalis californica) that I mentioned in last night's post continued this morning.  The butterflies seemed to be enjoying the morning sun on the south-facing walls of the Bodega Marine Laboratory.

Many of them were also probing the surface of the building with their proboscises.  I wondered what they might be interested in — could there be salt on the outside of the building?  Or were they just searching for moisture or nutrients?

They're such beautiful butterflies, and I just love the fall colors in their wings.  I took a few photos for the record: