Yep, the Giant Turkeys do have the ability to summon fowl now. They spawn a bunch of red birds (crows, eagles, turkeys, etc) which all proceed to attack you and do 1 damage each, with a high hit rate (making spellcasting impossible without Protection up). However, they can easily be AoEd down. Area peace making works good on them, and a Fire Horn kills them all.
In fact, i just took on a Giant Turkey with my Thrower and Bard/Mage, and area peacemaking seemed to trivialize the fight. My Thrower would continue swinging at full speed against the discorded Giant Turkey, even after my Bard area peaced, and the Giant Turkey would stand there for 5-10 secs doing absolutely nothing. As soon as the Giant Turkey became aggressive towards my Thrower, i'd area peace him again. Pretty easy kill.