It's a good thing that pigeons are not the size of Canada geese as they regularly try to fly through my living room windows. The impact on the glass is enough to set off the burglar alarm system as well as leaving the impression of a very surprised pigeon on the pane. Only one survived - the good people of the RSPB revived and released it. Once got involved with a P&W JT 9 that took 3 geese in the fan at JFK - much bent and torn titanium.