Daytime predators

I have been losing birds' like crazy this summer. 3 Gunia hens, and 4 chickens. My birds freerange all day and sleep in closed up coops at night. When we noticed a bird missing we would generally find a pile of feathers in the grass a day or two later. Leading me to suspect Hawks.

However, on Monday, something made off with 3 chickens (a massive Brama, an Americana, and a black Astrolop), and 1 gunia between 7 and 8pm. All we have been able to find is a 20 yard long trail of feathers from 1 bird. No guniea feathers, no black feathers.

I live in Southern Minnesota. Any ideas what kind of predator might take 4 birds during daylight hours, leaving little evidence behind?