Most of the lakes in Montana that are around around 10'000 ft. plus look a lot like that one and they usually have Brookies less than 10" long, more than likely average about 4". They stay small due to lack of feed and over producing. Many of these same lakes are stocked with Cutthroats that don't spawn and just get bigger and are usually hard to catch. I have never caught one that weighed more that 3 lbs. though. Some look like big snakes with huge heads. Not much food obviously.
The mountain range I am talking about is the Beartooths.

How high do you suppose that lake is in the picture? Beautiful shot by the way.

Ken