Try it out and see.
I've had a flock block in my chicken coop for about 2 months now. I didn't want to put it outside, I was afraid about two things: attracting rodents or other non poultry critters and afraid it would get buried in the snow.
I have 33 chickens. That original flock block is only about 1/3 gone. They really liked it the first few days then they forgot about it. A few will nom on it right before bed but that's about it.