In high School back in the 70's my buddies and I used to ice skate on the frozen estuary near my home with our shotguns and shoot coots out of the cattail swamps. It was like pheasant practice. we'd skate 2-3 miles along the unfrozen tidal areas and blast away. Hate to say we never even thought of picking them up. I think the limit at the time was 25 each.
