There are a quite a few Great Blue Herons in the Bay Area. They seem to be a solitary bird, since I usually see them alone. They build their nests in trees. Once, when I walked under a tree at Emeryville, CA, a Great Blue Heron gave a very large squawk and I jumped a mile.

To catch their prey, they walk very slowly in or near shallow water. Great Blue Herons eat fish, invertebrates, amphibians, reptiles, birds and small animals.