Why, I asked? And the reason, even though there was an element of speculation, surprised me. It seems that an osprey couple decided to build their nest on this site, and those nests can get quite large. It was not what the county engineers thought was a good idea, so they tore it down. The next year, the osprey couple returned to the same pole. So did the engineers, putting an end to the birds' home sweet home. They never returned.