Formal:
* La pêche blanche: This is the most common and direct translation, literally meaning "white fishing."
* La pêche sur glace: This translates to "fishing on ice" and is also a common and accurate way to say it.
Informal:
* La pêche à la truite sur glace: This is more specific and refers to ice fishing for trout.
* La pêche sur glace: This is a shorter, more informal way to say "fishing on ice."
Other:
* Pêche à la morue sur glace: This refers specifically to ice fishing for cod.
The best way to say it depends on the situation and the specific type of ice fishing you are referring to.