I'm starting this topic for the benefit of new anglers and others visiting the Rocky Mountain area for the first time. Appropriate stream etiquette here is very different than that on many stocked eastern rivers, and I think it might be helpful to have an introduction so well-meaning visitors won't accidentally do something they shouldn't.
I posted something similar on the PFS fishing report the last couple summers and got some kudos from fly-purchasers for it, so hopefully it'll help visitors here, too. I encourage everyone to keep an eye on their guides to make sure they follow these rules as well, because occasionally the chance at a good tip overrides ethics.

My comments below will focus exclusively on Yellowstone Park and the Yellowstone river. I hope locals/guides from other areas will post on their regions, because things are different in different watersheds. If the topic proves popular, it might become a sticky.

Without further ado...

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The primary unwritten angling etiquette rule in Yellowstone is not to crowd others. This is actually fairly complicated since "crowding" has a variety of meanings depending on water character and fame. What's appropriate on the Upper Yellowstone isn't appropriate on a random brookie creek, for example. I'll break this out into individual waters.

Small Streams Yellowstone has many small creeks, of which the majority are not famous but offer solitude and small, aggressive fish. In general, you want to stay away from other people. I often avoid fishing an area if I suspect another party is already fishing it. When this is not possible, I give other parties at least 100 yards both upstream and down.
Lakes If bank fishing, try to give at least 50 yards no matter the water. If in a tube, stay out of casting range of bank anglers. On Trout Lake and other waters with spawning closures, please do not cast past the "No Fishing" signs, as the closure arcs into the lake rather than cuts a straight line to the closure sign on the opposite shore.
Upper Yellowstone, Firehole, Gibbon Meadows, and Madison These rivers all feature long pools and runs that can support a large number of anglers. Try to give at least 50 yards between you and the next party, more in broken water stretches and on the Gibbon and Firehole. Avoid wading through water an angler is fishing or watching --it is helpful to rest water on these streams, so even if an angler is not fishing at the moment he may still be "working the water." Also, avoid walking on high banks when an angler is casting towards them.
Yellowstone River Canyons and other steep canyon water Try to give at least 150-200 yards of space between you and the next party. This large amount of space is generally necessary because of the need to work quickly through this type of water. Generally you can wade a bit closer on the downstream side if you wish, as most of the time anglers will be working upstream. Do not join others in the few pools unless invited.
Gardner, Gibbon Canyon, and other large pocket water streams Generally 100 yards is sufficient, with a little less appropriate when fishing opposite sides of the river during the high water of spring, when it is impossible to fish the entire width of the stream effectively. On roadside stretches it makes a bit more sense to come a bit closer, simply due to the popularity of these sections. Do not walk on high banks or allow your kids to throw rocks, even if there are good skippers around.
Lamar, Soda Butte, and Slough Creek These streams get crowded, so etiquette is very important on them. On Soda Butte, where there are well-defined pools fairly evenly spaced, it is NEVER appropriate to join another angler or party in a pool, no matter how long it is. During hatch situations, most anglers will work up and down through a pool several times before vacating it, so even if an angler is on the top/bottom of a long pool, the entire pool is theirs. Define a pool as the bottom of a riffle downstream to the top of the next. If possible, leave an empty pool between yourself and others before starting to fish to allow everyone a chance to move a bit without a long detour. Sometimes this is difficult. The Lamar is similar, save that its pools are generally longer. Slough Creek generally has much longer pools with ill-defined boundaries, so try to give at least 50 yards in the Lower Meadow, 100 in the campground stretch, 75 in the First Meadow, 125 in the Second Meadow, and 150 in the Third Meadow. On all three of these streams, as well as other curvy meadow streams, you should cross at the shallow tailouts of pools to walk on the gravel bar side of the stream (aka the low bank) rather than following a single side of the creek indefinitely. Unfortunately, there are usually trails along high banks. If you must walk on the high banks, step back at least 30 feet from these banks, especially if an angler is present in the pool.
Float Trips on the Yellowstone Gauge your responses to the number of boats on the river. In other words, you need to be more flexible when the Salmonflies are hatching on the 4th of July than in October. During crowded conditions, your boat should stay 20 yards away on the upstream side of other boats and 50 yards away on the downstream side, and be sure to stay out of back-casting range while passing. If possible, cross to the other side of the river, even if the holding water is not as good. When things are not as crowded, 100 yards is a bare minimum with the other side of the river a great option. Give wading anglers at least 50 yards upstream and down regardless of circumstances, with more upstream better. For spin-anglers, you should go to the middle of the river to stay out of casting range. White water rafters (even professional outfitters) frequently do not know to give this space, especially when setting up for rapids, so watch your backcast and be ready to ask politely that you be given more room.


If an angler or guided party (especially the latter) breaks any of the above rules, you are well within your rights to ask them to fish elsewhere, step back from the high bank, give you more room, etc. Try to do this politely, but feel free to be as forceful as you feel appropriate if politeness does not work. If a guided party gets snooty, try to find out who they're working for and contact their boss with any problems.