Every time we stepped out of the trailer, the killdeer went crazy.
They must have had a nest or two close by because there was always a bird or two pretending to be injured.
They would come right up to us and flop around dragging their wing hoping we'd follow them away from the nest.
They must have thought that they were always successful because they led us in the direction of the house (where we were headed anyway).
I heard on the radio while in Saskatoon that a number of killdeer and plover nests near Lake Diefenbaker had to be moved because of the heavy rains and flooding. These birds at my sister's place were in no danger.
The killdeer have a high-pitched shrill call (I wouldn't really call it a song). It was interesting to watch them perform.