A quick FYI -- a few years ago we had a small flock of chickens for our own eggs, and a couple of tame turkry's to keep em company -- they ate alot of grass hoppers around the place back then.
One day I had the brain storm of putting out Malrin for the flies, and never had a thought about the COLOR of the bait. If it had been brown like gravel, I would have never had a problem. Well, the darn poultry went to the color -- yellow -- like a magnet -- and they were all dead in less than a minute -- seriously! They dropped faster than the flies I wanted to kill!!!
Be carefull around any kind of bird life -- they love the stuff -- but it is deadly!