My sympathies for your loss. And your frustration.
Obviously having an affinity for crows, I am a bit ambivalent about this post. However: given the alternatives, I would recommend the method that Virgil suggested.
margin-left:40pxa. Does not present legal issues. (Like anyone needs more of those.)
margin-left:40pxb. Eliminates potential for non-target species contamination. (Spilled bait=potential for dead animals. Birds are messy eaters, even crows, ever had a parakeet?)
margin-left:40pxc. Most ethical. I can't see compassionate deer people wanting to chuckle at the suffering of any creature. (Varmint or pest included. Nobody I know anyway.)
margin-left:40pxd. Yes, they are intelligent birds, the message will resonate quite quickly among the flock. (and like children, they may need a second reminder)
margin-left:200px*Assuming you don't have the time or inclination to switch to gravity fed system.
There are some wonderful and inexpensive types available today.
Deer come first. Bottom line.