are birds eating too many dung beetles?
An ecologist wrote to me with the theory that 2007 has been a heavy year for bush flies because certain birds had discovered that dung beetles made tasty snacks. She had seen ibises and herons digging in cow pads, finding beetles, and eating them. I asked James Ridsdill-Smith at CSIRO for his comments. He emailed me as follows: It is interesting with the dung beetle program how people quickly forget how really bad the bush flies used to be. One would not expect the introduced beetles to be removing every scrap of dung produced, and you do not eradicate a major pest like the bush fly. The best you can hope for is to have an average level considerably lower than it was before. At times the flies will disappear and at other times there will be low numbers of flies. The birds like the ibises have always moved into the irrigation areas in the south of the state in summer. In the early days around 1980 I remember seeing them walking along the front of irrigation water as it moved over the pa
