With ice fishing season well under way in the northern states, I thought I would bring up a topic that I've been mulling over for awhile now. As most of us are aware, in order to prevent the spread of disease and exotics, it is against the law in most states to release live bait into public streams, ponds, rivers, lakes, etc... and (at least in my experience) most fishermen are aware of this and don't intentionally release bait. Something I have seen occasionally though, is the dumping of unwanted live bait onto the ice. The fishermen are trying to be responsible by not dumping it where it could survive, but what I am wondering is, from a disease standpoint, wouldn't this still be releasing them to the body of water? The minnows will surely die on the ice, but come spring their bodies will enter the lake, as will any disease organisms present in them and/or the bait water.

Seagulls and crows make a good living off discarded bait on the ice around my area. It's very doubtful a single discarded minnow would last a whole day unless covered by snow. At night foxes go from hole to hole looking for discarded bait [as their tracks in the snow attest].

Having said that, it's probably a better idea to take unwanted bait home to dispose of. It may even be the law in places.
That's where a big ole gar or bowfin would come in handy. Or a snapping turtle.

You typically lose some live bait into the water that you're fishing anyway. They come off the hook, or some lucky fish manages to eat your bait off the hook without being caught. So, just by using the live bait for fishing, if there are disease organisms present in the baitfish, you risk their transmission. That is why you should either use bait taken from the very water that you are fishing, or obtain certified disease-free bait from a state-licensed bait dealer. If you are doing this, I would think that dead baitfish are not a concern.

I would think that if the baitfish were collected from the same water that you are fishing, and exposed to no other fish, that the best thing to do would be to release them alive on the same day that they were collected. But if they were obtained from a bait dealer, you don't want them released alive, since you may be introducing breeders of a species that does not belong there.

However, you should also check your state regulations before using live bait. There may be specific requirements for removing or releasing baitfish.

Having said that, I like Mike's idea.

The fishermen are trying to be responsible by not dumping it where it could survive, but what I am wondering is, from a disease standpoint, wouldn't this still be releasing them to the body of water? The minnows will surely die on the ice, but come spring their bodies will enter the lake, as will any disease organisms present in them and/or the bait water.

Having said that, it's probably a better idea to take unwanted bait home to dispose of. It may even be the law in places.

I know this is a really old thread, but interestingly enough this is what Vermont law says about it:

5.4.6 Anglers shall not transport baitfish away from waters of the state by motorized vehicle. Baitfish may be held on the water in a pen or baitbox as per paragraph 5.2.2. Unwanted baitfish shall be discarded dead in the water or on the ice.

This is part of new rules put in place to combat spread of VHS. It seems pretty obvious to me that it'd be far better to ask anglers to dump the unused bait on the shore rather than back into the water or onto the ice. I'd suspect the rule is written more for enforceability than based on the best science: The way it's written, Fish and Game officers could issue a citation if they simply see an angler walk away from the shore with a bucket of bait. There's no room for argument about whether the angler was intending to bring them to another body of water or dump them in the woods before leaving...