When there is a frozen lake or pond please keep the dog on a lead. They are playful creatures and rely on us for guidance, just like a child.
Then you have idiots like these http://www.bbc.co.uk/news/uk-wales-south-west-wales-11967816
Intellect is something that differentiates Animals and Humans, what happened here ? Clearer not enough brain cells allocated to these lucky 13! Waste of time for the rescue team!