I have noticed this summer that we only seemed to have one pair of Purple Martins that stayed around and successfully raised a chick in one of our Saguaros and I was curious as to why, in a year that has seen apparently great rearing success amongst most other bird species why they hadn't done so well. I think I may have found the culprit.
The Brown-crested Flycatchers have chosen to use the same group of Saguaros as the Purple Martins to nest this year and they are known to be particularly aggressive during nesting season, often driving other bird species away. Such a shame, I do so enjoy having the martin families swirling around over head with their beautiful warbling calls.