These strips have that notation because they are, in fact, HAZARDOUS!
That is, to pilots without extensive mountain experience. And even sometimes to those of us with that experience.
Fish Lake has one of the worst accident histories of any Idaho strip!
This is because it looks so benign from altitude, and most folks are not aware of how powerful a downdraft a meduim sized lake in a high mountain valley can generate. There is also NO go-around. And moose. Lot's of them...as well as deer and elk, especially late in the afternoon. If you have that happen on short final you MUST continue the landing and hit the animal if necessary! Departure, even in a 185 or Super Cub, should be below 85 degrees, 70 degrees for the rest of us. Count on a tailwind on departure before 10 am.
Moose Creek is hazardous because it also looks benign, but it is at the junction of two large canyons and can have serious turbulence on approach or departure if the wind is blowing. It has a runway long enough for a cabin class twin, but departure from that runway requires a 90 degree turn 1/4 mile off the end to avoid the canyon wall which is perpendicular to the runway heading. Again, not a strip for someone without a local check out, unless they are in a Super Cub or similar. It does, however, have the most delightful camping and is a favorite among us.
Shearer is actually more dangerous than Fish Lake, but it does not have as bad an accident history because it LOOKS really hairy. It also has wildlife and no go-around below 300 feet, and it has one of the worst approaches in the state. You must fly around a mountain off the north end of the strip, avoid another strip at a private lodge, hug the ridge on your right while descending into the canyon and make a right 90 onto final at 200 feet or less. You have now been out of sight of the strip for 3 to 4 minutes and you have 5 seconds to decide if you will commit to it.
THAT is why these strips are noted as hazardous, and I haven't told half of it.
Get Galen Hanselman's book "Fy Idaho" and use it as your bible for our backcountry strips. Even if you have lots of mountain experience you will STILL need local instruction. Even after 30 years of flying Idaho I still seek up to-date local advice on each strip in the week or so before. For instance, several years ago someone who disliked airplanes put a salt block in the middle of the runway at Shearer in the late Fall with the result that elk trashed the runway at that spot and it was several years before the strip was in good shape again.
Y'all be careful out there!
Rocky