here is a link to the fishing seasons:
http://www.wildlife.state.nh.us/fishing/seasons.html
Note the All other Species near the bottom. Particular attention to bullet 3 Italicized and underlined. In lake trout and or salmon waters, 1-1 to 1-31 is ice fishing only, not open water.
All Other Species
- Rivers & Streams: January 1 - October 15
- Trout Ponds: 4th Saturday in April - October 15
- Lake Trout and/or Salmon waters: No closed season (Fish can be taken by ice fishing only January 1 – March 31)
- All Other Waters: No closed season