Crossword puzzle clue "six foot avians"

Six-foot avians

"Six foot, seven foot, eight foot ___!"

Six-foot vis-à-vis five-foot

Six-foot six-toed Aussie

Campaign about which Rumsfeld said in 2003 "it could last six days, six weeks - I doubt six months"

Tropical avians

Extinct avians

Wiped-out avians