Dog hunting chicks...
My suggestion would be to do training with an E Collar (aka shock collar). If it's done correctly, it can be very humane and very effective. That would be my first choice, but it would require a decent amount of effort, time, and money down on the collar. You would only want to use a Dogtra, absolutely nothing that they sell at the pet store. Dogtra collars have 127 different levels of stim, and the lower levels feel very much like a tens unit and are not painful. I have taught my dogs (two GSDs) that the stim is the equivalent of being tugged by a leash and they yield to it in that manner. It is not traumatic or scary for them it is simply a boundary. The field level Dogtras have a 1 1/2 mile radius so you can use your "magical powers" from the kitchen if your dog is outside.
Second choice beyond that would be a Dogtra invisible fence system as a boundary a safe distance away from the chicken coop. You still have to invest time and money but not as much of either. The drawback is that the automatic collar will use higher stim than you would if you were doing it by hand. There is a possibility of traumatizing the dog if it is done wrong. However, the risk of a slight fear/pain response in a dog that also puts an end to predatory behavior which might threaten the life of chicks/ life of the dog in the long run? You gotta make a judgment call.
I realize some of this is more intense than is necessary for this beagle (although the idea of allowing the dog to continue staring at the chicks through the wire rubs me the wrong way) but if anyone else has predatory problems and wants advice on how to use an E Collar I would be happy to email about it. and I don't sell Dogtras! They just are the best there is. Tri-Tronics is second best.
Someone else mentioned the possibility of physically harming the dog by yanking. This is a real issue, especially depending on the collar. E Collars cause no physical harm. They are quite safe and reliable. (The expensive ones anyway. I have a very low opinion of the cheapie brands, you get what you pay for)