A rarity here in California, this is an adult female returning to winter in the same tree where it spent last winter. This sort of site fidelity is called "philopatry" and is quite common in migratory birds. Sapsuckers are a group of rather quiet secretive woodpeckers that feed not by sucking sap, but by drilling short wells into the cambium layer of living trees and returning to lick the sap that bleeds out. These wells eventually scar over leaving tell-tale markings in neat rows around the tree trunk. Canon SX70 HS.