Are Northern Cardinals here is Arizona really what they seem to be? Research suggests at least some southwestern populations could be separate species. Bird feeder hygiene tips to ward off bird disease including among hummingbirds. Bird of the week: Acorn Woodpecker; Birding hotspots: Sweetwater Wetlands and the Arivaca Cienega IBA in southeastern Arizona. Friend-of-Wildlife agency: Grand Canyon Trust. Calendar of bird-friendly events coming up in Arizona.