Drone helps conservation group with the threatened sandhill crane

Look! Up in the sky! It's a bird! It's a plane! Actually, it's tens of thousands of birds and a single drone, an unmanned flying machine with a wingspan the size of an extra-large pizza. And on a recent afternoon, while the birds land, flit and flutter in the plowed cornfields and watering holes of the California Delta, it's not Superman we see but a drone hovering 125 feet overhead, whirring like a weed-whacker, its attached camera recording the avian lovefest down on the ground.