Los Angeles Times: There was a time when it was hard to find yellow warblers at Rush Creek. But on a recent bright and sunny morning, a yellow warbler plunged through a gap in a stream-side cottonwood forest, flying back to the nest where her chicks were hiding. Suddenly, she was stopped in midair, tangled in a mist net. Field biologist Chris McCreedy found the bird in his snare a few minutes later. “Hi there, sweetie,” McCreedy said as he set to work. He untangled the bird, recorded its vitals …