An unintentional one, but the sounds the birds - which look like hawks or Aquila eagles - produce are made by Bald Eagles. Due to the rather annoying and unimpressive nature of the Bald Eagle call, they are dubbed in fiction with the cries of other birds of prey. So basically, not only is that situation reversed here, but in a way it's very karmically appropriate.
Ramsey is an Iraq vet who is clearly suffering from some sort of PTSD. He spends the film running around in military fatigues and combat boots, and he had an assault rifle and several pistols in his creepy van. If the bird attack didn't occur, it seems quite likely that he was getting ready to do a mass shooting sometime soon, or is at least a very dangerous and unstable individual.