WILDLIFE STRIKES TO CIVIL AIRCRAFT IN THE UNITED STATES, 1990–2007
"A mixed flock of blackbirds (red-winged blackbirds, common grackles, brown
-headed cowbirds) and European starlings descend into a wooded roosting area at dusk, less than 2 miles from a southern USA airport, 11 January 2007. Over 500 million blackbirds and starlings from Canada and the northern USA migrate to the southern USA each winter where they gather nightly in numerous roosts in marshes
and woodlots. Flight lines of birds entering to and departing from these roost
sites at dusk and dawn can pose a serious risk to aircraft at nearby airports. Airports should work with nearby communities to prevent large bird roosts from developing near airports. Photo, S. Stopak, USDA.

The most deadly civil (62 human fatalities, Massachusetts 1960) and military (34
fatalities, Netherlands 1996) bird strikes were caused by flocks of starlings."