In case you're keeping track, there hasn't been any research yet showing how the drought is great for birds. On the the other hand, there've been plenty showing how the drought is hurting them. Here's another on the latter side, showing how drought is actually reducing birdsong in the San Gabriel Mountains:
"Jenny Rechel has been studying birds in the San Dimas Experimental Forest above Glendora for 19 years. These days, she's hearing fewer species come through — a result of the historic four-year drought that continues to plague the state. Seems like there’s fewer bird calls," the U.S. Forest Service researcher said. "I hear less calling, especially in the areas by the streams."
HOTSPOT: Flyover of California's Birds and Biodiversity
California is a global biodiversity hotspots, with one of the greatest concentrations of living species on Earth.