A few of my favorite shots of great blue herons hunting gophers in San Francisco's Golden Gate Park and Presidio. They do this mostly in the spring when they have chicks to feed. If you ever see a heron standing in the grass, take a few minutes to watch it patiently from a distance. It's well worth the wait when they finally catch one. My understanding is they listen and feel for vibrations and then home in on the gopher until they get a visual before going in for the kill.