Rat Lake near Big Sky: Fishing Spots, Seasons and Access

• Overview

  Rat Lake lies within the bounds of Gallatin County, Montana. It sits in rolling bush country. Small at around 13 acres: two anglers spread out cover most of it. Size puts it in the front rank of our Gallatin County list. Big Sky sits 13 miles from the bank. It is 132 miles to Billings, the nearest city. The nearest edge is a long way off, so local rules apply throughout.

• Where to Fish on Rat Lake

  Nothing in our records gives a depth for this one. A natural lake fishes on cover, and cover here means weed and timber. A soft bed grows weed late into autumn, which keeps fish shallow. Across Gallatin County, recorded fish include rainbow trout, brown trout, brook trout, mountain whitefish and black-spotted cutthroat trout. Read it as a county summary, not a water-by-water list. Take Rat Lake a stretch at a time.

• Seasonal Patterns

  The range across the year is 21°F to 59°F. The year splits cleanly: hard water, then open water. Hard water holds through the cold months, breaking up near late April. Average temperatures cross freezing around late April in spring and again near late November in autumn. The strongest runs come at either end of the open season. That shapes the year on Rat Lake.

• Tackle & Baits

  The paperwork position is blank for this one. Recorded parking is half a mile off, far enough to travel light. For the trout, small spinners and a box of nymphs cover both approaches. Bank access can be seasonal on ground like this. Some ground is open by custom rather than by right, so tread carefully. If the gate is shut, Pioneer Lakes at 1.4 miles is the nearest alternative. The position on Rat Lake is worth confirming on the day.