Fishing Regulations

2022

Yellowstone National Park 

Park biologists are conducting a study to determine native cutthroat 

trout movement patterns and population size in Yellowstone Lake. 

Learn more on page 15.
Purpose of Yellowstone Fishing Regulations 

Fishing regulations in Yellowstone National Park are structured to strongly 

support native fish conservation goals. Cutthroat trout are the sole, native 

trout of the park and were the dominant fish species here prior to 

Euroamerican settlement. Cutthroat trout, Arctic grayling, mountain whitefish, and other native fishes are important to the ecology of Yellowstone. 

Introduced nonnative fish cause loss of native fish 

The abundance of native fish has been reduced because of impacts by introduced nonnative fish, including brook, brown, lake, and rainbow trout. These 

nonnative species continue to contribute to the decline in the park’s native 

fish population by competing for food and habitat, preying on native fish, and 

degrading the genetic integrity of native fish through hybridization.

Anglers assist with native species conservation

Angling is one way that the nonnative fish can be selectively removed 

from an area without damaging the native fishery. Within the Native Trout 

Conservation Area, anglers are strongly encouraged, and in some cases 

required, to harvest nonnative fishes. This harvest will help to conserve the native fish and the natural ecosystems they support.

Stay Safe and Legal

You are responsible for following all park regulations. Consult Yellowstone’s 

park visitor guide, Backcountry Trip Planner, or rangers at visitor centers and 

backcountry offices to learn more.

• Stay on established trails in thermal areas for your safety and to protect these 

fragile areas.

• Do not discard fish carcasses or entrails along stream banks or the lake 

shore as they will attract bears. 

• Do not feed any animals, including birds, squirrels, and coyotes. 

Bear Warning • Bears and other wildlife may appear in areas frequented by 

people—even on trails, boardwalks, and along roads. Do not approach wildlife 

and remain at least 100 yards (92 meters) away from bears and wolves, and 25 

yards (23 meters) away from all other wildlife. 

• Be alert—watch for bears and bear sign, like fresh tracks or scat.

• Make noise in areas where visibility is limited.

• Carry bear spray and know how to use it. 

• Avoid hiking or fishing alone. Try to 

stay with a group of three or more people. 

• DO NOT RUN if you encounter a bear. 
1

Contents

General Regulations ....................................................................... 2–6

Seasons, dates, fishing hours, permit requirements, tackle restrictions, catch 

and release, mandatory kill, and possession limits.

Fishing................................................................ 2

Boating ............................................................... 6

Releasing Fish.................................................................................. 7

Regional Regulations...................................................................... 8–15

Summary and exceptions to general regulations for each region of the park.

Northwest Region Regulations....................... 8

Northeast Region Regulations........................ 10

Southwest Region Regulations........................ 12

Southeast Region Regulations......................... 14

Fish Identification ........................................................................... 16–20

Know each fish species on sight in order to comply with native trout 

conservation requirements.

Native ................................................................. 16

Nonnative .......................................................... 18

Angler Etiquette.............................................................................. 21

Frequently Asked Questions .......................................................... 22

Glossary ........................................................................................... 24
2 

General Regulations

Fishing

Fishing/angling is defined as any 

activity using an attended single rod 

or line for the purpose of attempting to attract, capture, or possess any 

fish from waters within Yellowstone 

National Park. All other methods to 

attract, capture, or possess fish are 

prohibited. 

Fishing hours and season dates

The season begins the Saturday 

of Memorial Day weekend (usually the last weekend in May) 

and extends through October 31.

Exceptions are listed in regional 

regulations (p. 8–15) and include 

Black Tail Pond, Heart Lake, and the 

Yellowstone River (open July 1). 

Hours are daily from sunrise to 

sunset. Fishing with an artificial 

light is prohibited. Some areas are 

closed to human entry, have trail or 

seasonal closures, off-trail travel and 

daylight hour limitations, or party 

size recommendations. See the Bear 

Management Area restrictions in the 

Backcountry Trip Planner for specific 

rules and information.

Streams may be temporarily closed due 

to low water levels and high water temperatures to protect fish populations.

Fishing permits

Anglers 16 years of age or older 

must be in possession of a valid 

Yellowstone National Park fishing 

permit to fish in the park. 

Park rangers may check permits and 

inspect tackle, fish, creels, or other 

containers where fish or tackle may 

be stored.

Anglers 15 years of age or younger 

have two options:

1. Children 15 or younger may fish 

without a permit if they are fishing 

under the direct supervision of an 

adult who has a valid park fishing 

permit.

2. Children 15 or younger may obtain 

a free permit that must be signed by 

a responsible adult; with this permit, a child can fish without direct 

adult supervision. 

With either option, the accompanying adult is responsible for the child’s 

actions and must ensure the child 

complies with all fishing regulations 

and provisions. 

Gear restrictions

Each angler may use only one rod, 

which must be closely attended 

at all times and used for angling 

only—intentional snagging of fish is 

prohibited.

Only lead-free artificial lures 

(e.g., spoon or spinner) or flies may 

be used. Leaded fishing tackle such 

as leaded split-shot sinkers, weighted 
3

jigs (lead molded to a hook), and soft 

lead-weighted ribbon for nymph fishing are not allowed. 

Hooks must have points that are 

barbless, or the barbs must be 

pinched down by pliers. Lures may 

have only one hook with single, 

double, or treble (triple) points on a 

common shank. 

Each fly may have only one hook. Up 

to two flies may be used on a single 

leader (also called “dry and dropper” 

or “hopper and dropper”).

Except for feathers and other typical 

fly-tying materials, the hook must be 

bare. No organic or inorganic baits 

are allowed. Organic baits include 

fish or fish parts, minnows, salmon 

eggs, worms, insects, or foodstuffs 

such as bread or corn. Inorganic baits 

include rubber worms and plastic 

“twister” tails. Scented attractants 

(liquid and solid baits) are illegal. 

Putting any substance in the water for 

the purpose of attracting fish (chumming) is illegal.

Felt-soled footgear prohibited

To reduce the potential for 

introduction or spread of aquatic 

invasive species, footgear with 

absorbent felt or other fibrous 

material on the soles are prohibited.

Tackle exceptions 

Non-toxic split-shot, sinkers, and jig 

heads molded with bismuth-tin, molybdenum, or tungsten are allowed. 

Lead core line and heavy (> 4 lb.) 

downrigger weights used to fish for 

deep-dwelling lake trout are permissible because they are too large to be 

ingested by wildlife.

Artificial lures are not allowed on the 

Firehole River, Madison River, and 

lower Gibbon River (below Gibbon 

Falls); these streams are fly fishing 

only.

General Regulations

A single pointed hook is the best choice 

for fishing in Yellowstone. Three-point 

hooks can severely injure fish and are 

often constructed with toxic lead solder.

FAQ: Why are barbless 

hooks required?

Barbless hooks reduce injuries 

and the time needed to handle 

fish and improve the overall 

condition of trout in heavilyfished waters of the park.

FAQ: Why is fishing leadfree in Yellowstone?

Lead is a toxic environmental 

contaminant. It accumulates in 

fatty tissue, eventually causing lead poisoning. Wildlife 

such as waterfowl, cranes, 

and shorebirds are vulnerable 

because of their largely fishbased diets. 
4 

General Regulations

Yellowstone River

Madison River

Gibbon River

Fireho el River

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! !

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Madison

Norris

West 

Entrance

Old 

Faithful

Mammoth

North 

Entrance

Tower

Canyon

Fishing Bridge

Lake

Bridge 

Bay

West Thumb

Grant 

Village

South 

Entrance

East

Entrance

Northeast

Entrance

Bechler

Yellowstone

Lake

Slough Cr.

Soda Butte Cr.

Lamar River

0 5 10 20 miles

1

Streams

Roads

Park Boundary

Region Boundary

Nonnative Trout Tolerance Area

Native Trout Conservation Area

NORTHEAST

REGION

SOUTHEAST

REGION

SOUTHWEST

REGION

NORTHWEST

REGION

Possession limits

All native fish must be released 

unharmed. Natives include cutthroat 

trout, mountain whitefish, and Arctic 

grayling. See pages 16–17 for photos 

and further descriptions.

Each angler must be able 

to correctly identify various 

fish species.

ALL NATIVE FISH MUST BE 

RELEASED UNHARMED
5

General Regulations

Native Trout Conservation Area

All native fish must be released unharmed. No possession limit for nonnative fish, including brown, brook, rainbow, 

and lake trout (p. 8–15). 

• All rainbow trout, brook trout, and 

identifiable cutthroat × rainbow 

hybrids caught in the Lamar River 

drainage (including portions of 

Slough and Soda Butte creeks) and 

the Yellowstone River drainage below Lower Falls and above Knowles 

Falls must be killed—it is illegal to 

release them alive (p. 10). 

• All lake trout caught from Yellowstone 

Lake must be killed—it is illegal to 

release them alive.

• All smallmouth bass caught in 

Yellowstone Park must be killed and 

reported—it is illegal to release them 

alive.

Nonnative Trout Tolerance Area

All native fish must be released unharmed. Possession limits exist for 

nonnative fish in this area. An angler must 

cease fishing in the area immediately after 

filling the possession limit (p. 9 and 12).

• Firehole River, Madison River, lower 

Gibbon River (downstream of Gibbon 

Falls)—possession of up to five brook 

trout is allowed. Catch and release all 

rainbow and brown trout. Whitefish 

are an important native species in 

the Madison River and they must be 

released. 

• Lewis River system above Lewis Falls, 

including Lewis and Shoshone lakes 

and their tributaries—possession of 

five combined brook, brown or lake 

trout; only one of which may be a 

brown trout. 

It is the responsibility of the angler 

to be able to identify fish by species. 

Unintentionally killed fish should be 

returned to the water so they can be 

consumed by wildlife. 

Brook trout markings.

Evidence of species in possession

Skin must remain attached so the 

fish species can be visibly identified. 

Gills and entrails may be removed 

in the field, but must be discarded 

only within the waters where the fish 

were caught.

Disposal of fish and entrails

Dispose of fish and/or fish entrails 

within the waters where the fish 

was caught but not within 100 feet 

(30.5 m) of boat ramps, docks, or 

backcountry campsites. Fish can also 

be disposed of in park trash cans. 

Bridge, marina, and boat dock 

restrictions

No fishing from any road bridge, 

marina, or boat dock.* Accessible fishing platforms and ramps are located 

near Madison Junction (p. 8) and at 

Grant Village boat launch (p. 14).

*Fishing is permissible from boat docks at 

backcountry sites on Yellowstone Lake.
6 

General Regulations

Aquatic invasive species jeopardize the ecological, recreational, 

and economic values of the entire 

Yellowstone area. Please protect 

Yellowstone waters:

1.CLEAN water, mud, plants, fish, 

and all other foreign material from 

your boats, trailers, and other 

equipment—including waders, 

boots, clothing, and nets—use 

high-pressure, hot (>140°F) water 

to treat all gear before you enter 

Yellowstone National Park.

2. DRAIN your boat hull and live well 

in a safe location (a flat, paved, 

dirt, or gravel area) away from all 

park surface waters. Do not dump 

water from other sources into 

Yellowstone waters.

3. DRY. Ensure all gear is clean and 

completely dry for 5 days—including waders, boots, clothing, 

and nets—before fishing another 

stream or lake in the park. 

4. DO NOT BRING BAIT into 

Yellowstone National Park. No 

natural or organic bait such as minnows, salmon eggs, worms, insects, 

or foodstuffs—alive or dead—are 

allowed. 

5. NEVER MOVE water, fish, other 

animals, or plants from one stream 

or lake to another. It is illegal to 

transport live fish within the park.

See Yellowstone’s aquatic invasive 

species brochure or the park website 

for additional details.

Boating

Vessel inspections & permits

The boating season begins the Saturday 

of Memorial Day weekend and extends 

through October 31. All vessels—including float tubes—require a boat 

permit, a life vest for each passenger, 

and an emergency sound device such 

as a whistle or air horn. All vessels must 

be checked by NPS inspectors to ensure 

they are free of aquatic invasive species 

before entering any park waters. See 

Yellowstone’s Boating Regulations or 

All vessels, including float tubes, require visit go.nps.gov/YELLais for details.

an inspection and a permit.
7

Releasing Fish

Hold the fish with wet hands, beneath the 

belly, behind the pectoral fins. Use forceps 

or small pliers to remove the hook. 

For all native fish and any nonnative 

fish you intend to release, bring the 

fish in as quickly as possible. Do not 

play the fish to exhaustion.

Unhook the fish in quiet water such 

as an eddy or slow spot. Do not drag 

the fish across land. Use forceps or 

small needle-nosed pliers to quickly 

remove the hook.

Always make sure your hands are 

wet if you must handle the fish. Dry 

hands damage a fish’s protective 

mucous film. Hold the fish with one 

hand around the tail section and the 

other beneath the belly, just behind 

the pectoral fins. Never grab or hold 

a fish through the gills unless it is 

already dead.

If you want a photo of the fish, make 

sure the photographer is ready before 

you handle the fish. Make it quick.

Never just throw a fish back into 

the water. If a fish becomes passive, 

it is probably close to exhaustion. 

Gently remove the hook within calm 

water, then lightly cradle the fish with 

your hands to see what it does. If it 

struggles to keep itself upright, hold 

the fish around its tail and beneath its 

belly with its head facing upstream 

into the current. Move the fish gently 

back and forth toward and away 

from the current. You should notice 

the gills opening and closing due to 

the rush of water. This is like giving 

a fish mouth-to-mouth resuscitation. When the fish has recovered, it 

should swim away on its own.

Tackle, lures, and hooks

Hooks and lures typically have barbs 

when purchased. With small pliers 

you must pinch down the barbs. 

Without barbs, more skill is required 

in landing and bringing in fish, but 

hook removal is easier and less traumatic to the fish.

Spinning lures typically have one 

hook with three points on a common 

shank, which is called a treble hook. 

With wire cutters you can snip off 

one of the points or snap one off with 

pliers; you also must pinch down all 

the barbs. Two pointed hooks are still 

effective, easier to remove, and less 

traumatic.

If the fish is deeply hooked, cut the 

line, do not pull out the hook. Most 

fish can survive with hooks left in.
8 

Regional Regulations

If a stream or lake is not listed by name or as a tributary, general regulations 

apply. You must follow bear management and hydrothermal area restrictions 

listed in the Backcountry Trip Planner, which is available in backcountry 

offices or at www.nps.gov/yell/planyourvisit/backcountryhiking.htm. 

Northwest Region:

Includes the Madison and Gallatin 

river drainages, including Firehole 

and Gibbon rivers and tributaries.

Permanently closed to fishing: 

• Firehole River from road bridge 

.5 mile (.8 km) upstream of Old 

Faithful to road bridge at Biscuit 

Basin, 200 yards (182 m) either side 

of Midway footbridge.

• Madison River from Seven Mile 

Bridge upstream 250 yards (226 m).

Fly fishing only: Madison River, 

Firehole River, Gibbon River below 

Gibbon Falls (not including their 

tributaries). Use only artificial flies 

regardless of the type of rod or line.

Possession limits 

Native Trout Conservation Area:

• Catch and release all native fish.

• No possession limit on nonnative 

fish. 

Nonnative Trout Tolerance Area:

• Limit of 5 brook trout.

• Catch and release all rainbow and 

brown trout. 

Where to take young anglers

Norris: Gibbon River at Virginia 

Meadows or other meadows; 

Solfatara Creek near Norris 

campground.

Madison: Gibbon River near Tuff 

Cliffs; Large meadow areas of the 

Firehole, Gibbon, and Madison rivers near Madison Junction.

Old Faithful: Firehole River at picnic 

areas; Nez Perce Creek.

ô Accessible ramp & platform

At the Mount Haynes Overlook, 

approximately 3.5 miles (5.6 km) 

west of Madison Junction. Please see 

the Yellowstone Accessibility Guide

or www.nps.gov/yell for more 

information.
9

Northwest Region Regulations

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Madison

Norris

West

Entrance

Old

Faithful

Spec imen

Fan

Gallat in

Grayling

Du ck

Gneiss

Cougar

Ma ple

Cougar

Gibbon Madison Firehole

Nez Perce

F airy

Little F irehole

Firehole

Ice

Lake

Wolf

Lake

Grebe

Lake

Gibbon

Seven

Mile

Bridge

Midway Foot

Bridge

HWY 191

To Mammoth

To 

Canyon

To Grant

Village

Roads

Flyfishing ONLY

Closed to all fishing

Nonnative Trout Tolerance Area

Native Trout Conservation Area

Park Boundary

Bear Management Areas

Accessible Ramp & Platform

CT

CT

MW

BN

RT

GY

MW

BN

RT

GY

CT

MW

BN

RT

BK

BK

BK

BN

CT

GY

CT

BK

BN

RT

BK

BN

RT

BN

RT

BN

BK

RT

GY

CT
10 

Kno

Fal

,,,,,,,,

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•

•

Madison

Norris

Mammoth

Can

North Entrance

Gardiner, MT

Gle

G

n

a rd

ner

Indi an

Obsidian

Blacktail

Pond

Gar dner

Lava

Bla

Joffee

Lake

To Norris

BK

BK

CT, MW, 

BK, BN, 

RT

BK

BK

BK

BK

SB 

Northeast Region Regulations

• Blacktail Pond area is closed to 

public use and travel, including angling, until July 1 to protect nesting 

birds and sensitive vegetation. 

• Only a State of Montana fishing license is required to fish the 

Yellowstone River downstream of 

its confluence with the Gardner 

River at Gardiner, MT, and 

only State of Montana Fishing 

Regulations apply.

Permanently closed to fishing:

• Trout Lake inlet stream is permanently closed to fishing to protect 

spawning cutthroat trout.

• Yellowstone River, from 

Chittenden Bridge near Canyon 

downstream through the Grand 

Canyon of the Yellowstone to a 

point directly below Silver Cord 

Cascade, is permanently closed to 

fishing to ensure angler safety.

Northeast Region:

Includes the Yellowstone and Lamar 

rivers and tributaries between the 

north park boundary and Chittenden 

Bridge near Canyon.

Possession limits

Native Trout Conservation Area:

• Catch and release all native fish.

• No possession limit on nonnative fish. 

All nonnative fish, including rainbow trout, brook trout, and identifiable cutthroat x rainbow hybrids, 

must be killed in these areas:

• Lamar River drainage including all 

tributaries and lakes.

• Yellowstone River below Lower 

Falls and above Knowles Falls, 

including north side tributaries.

In areas downstream of these locations, killing of nonnative fish is 

recommended. Smallmouth bass 

caught anywhere in the park must 

be killed and reported.
11

owles 

ls

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•

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nyon

e

Tower

Northeast

Entrance

Tower Fall

Silver Cord Cascade

Chittenden Bridge

Trout Lake

McBride

Lake

Blackta il

He ll ro

ar ni g

Tower

Cache

La mar

Yellowsto ne

Bu ffalo

Slough

Pe

bble

Soda Butte

Roads

Closed to all fishing

All rainbow trout, brook 

trout, and identifiable 

cutthroat x rainbow trout 

Park Boundary hybrids must be killed.

Native Trout 

Conservation Area

Bear Management Areas ,,, Yellowstone River downstream of its confluence 

with the Gardner River: 

Only a State of Montana 

fishing license required.

CT

CT

CT

CT

CT

CT

RT

CT

RT

CT

RT

CT

RT

CT

RT

CT RT

RT 

CT

Northeast Region Regulations

Smallmouth bass have recently been 

found near the confluence of the 

Gardner and Yellowstone rivers. 

If caught, they must be killed and 

reported. See page 20 for more.
12 

Southwest Region Regulations

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Old Faithful

Bound ary Creek

Shoshone 

Lake

Lewis

Lake

Lewis

Falls

Lewis

 Channel

H

L

Bec hler River

F alls River

Lewis River

DeLa cy

Snake River

South Entrance

Bechler

Old Faithful

West 

Thumb

Grant

To 

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CT

CT

RT

BK 

CT

BN

CT

MW

LT

BN

BK

LT

BN

BK

LT

CT

RT

CT

RT

Includes the Snake and Lewis rivers and tributaries; Heart Lake; 

Lewis and Shoshone lakes; Falls and 

Bechler rivers and tributaries.

Heart Lake opens July 1.

Possession limits 

Nonnative Trout Tolerance Area:

• Waters above Lewis Falls, including 

Lewis and Shoshone lakes and the 

Lewis Channel—possession limit 

of five nonnative fish in combination, only one of which can be a 

brown trout.

Southwest Region:
13

Southwest Region Regulations

Western shore of Shoshone Lake.

!

Heart

Lake

Snake River

Roads

Nonnative Trout Tolerance Area

Native Trout Conservation Area

Bear Management Areas

Park Boundary

 Lake

CT

CT

CT

MW

• Do not discard lake trout carcasses 

along the lake shore as they will 

likely attract bears.

Native Trout Conservation Area:

• Catch and release all native fish.

• No possession limit on nonnative 

fish. 

Where to take young anglers

Grant: Lewis Lake shoreline; pullouts 

along the South Entrance Road. 
14 

Southeast Region Regulations

Southeast Region: 

Includes the Yellowstone River 

upstream of Chittenden Bridge near 

Canyon, Yellowstone Lake and its 

tributaries, Middle Creek of the 

North Fork Shoshone River.

Yellowstone River and its 

tributaries open July 1 except the 

permanently closed areas listed 

below. 

Permanently closed to fishing on 

the Yellowstone River:

• Fishing Bridge and an area one 

mile (1.6 km) downstream (toward 

Canyon) and 1/4 mile (.4 km) upstream (toward Yellowstone Lake) 

from the bridge.

• The Yellowstone River 100 yards 

(91 m) up- and downstream of 

LeHardys Rapids.

• The Yellowstone River and its 

tributaries in Hayden Valley from 

the confluence of Alum Creek upstream to Sulphur Cauldron. 

Yellowstone Lake opens with the 

general season

Streams flowing into Yellowstone 

Lake, its tributaries, and areas 

within 100 yards (91 m) of each 

stream’s outlet open July 15. Access 

to many areas is restricted by Bear 

Management Area Closures, see 

the Yellowstone Backcountry Trip 

Planner for details. 

Permanently closed to fishing 

along Yellowstone Lake:

• The shoreline of Yellowstone Lake 

from West Thumb Geyser Basin 

to Little Thumb Creek is closed to 

protect fragile thermal resources.

• Bridge Bay Marina/Harbor and 

Grant Village Marina/Harbor and 

their channels to the lake. 

• Pelican Creek from its mouth to a 

point two miles (3.2 km) upstream.

Possession limits 

Native Trout Conservation Area:

• Catch and release all native fish.

• No possession limit on nonnative 

fish. All lake trout must be killed.

Where to take young anglers

Lake Village: Along Gull Point Drive or 

at Sand Point.

Grant: Lewis Lake shoreline; 

Yellowstone Lake shoreline near 

Grant Marina.

ô Accessible ramp & platform

An accessible fishing area is located 

at the Grant Village boat launch. 
15

!

!

!

!

!

! !

!

!

Norris

Grant

Bridge

Bay

West

Thumb

Lake

Fishing

Bridge East 

Entrance

Otter

Yel lo

w stone

A lum

Tr out

Elk

Antler

Columbine

Middle

Yello

ws tone

Arnica

LeHardys

Rapids

Mud

Volcano

Sulphur

Cauldron

To Canyon

To South

Entrance

To

Old 

Faithful

Roads

Closed to all fishing

Native Trout Conservation Area

Park Boundary

Bear Management Areas

CT

CT

CT

CT

CT

CT

CT

CT

CT

CT

CT

CT

CT

LT CT

BN

BK

RT

CT

Southeast Region Regulations

Park biologists are conducting a study to determine native cutthroat trout movement patterns 

and population size in Yellowstone Lake. Park 

biologists attach a floy tag near the fish’s dorsal 

fin. The tags are typically orange or yellow in 

color and have a unique identification number.

If you catch a tagged cutthroat:

1. Record the tag number (photo or written) 

and release the fish unharmed.

2. Note the location the fish was caught.

3. Call or text 406-404-4877 and report the tag 

number and location of catch.

4. If the fish accidentally died, please include 

that detail in your report.

Floy tag.
16 

Fish Identification—Native

Cutthroat trout subspecies

few spots on head

dark spots on light 

background

red or orange jaw 

slash

Each individual angler must be able to correctly identify various 

fish species and comply with appropriate rules and regulations.

ALL NATIVE FISH ARE CATCH-AND-RELEASE ONLY

Widely distributed in many drainages.

Yellowstone cutthroat trout (large-spotted 

form; Oncorhynchus clarkii bouvieri).

Westslope cutthroat trout (Oncorhynchus 

clarkii lewisi). 

Two subspecies of cutthroat trout are found in Yellowstone: the westslope cutthroat and the Yellowstone cutthroat (which has both large- and finespotted 

varieties). 

Cutthroat Trout—CT
17

large scales

Fish Identification—Native

large, sail-like 

dorsal fin

Distributed throughout Gibbon River, 

sometimes in Madison and Firehole rivers.

dark spots on front 

half of body

Arctic Grayling—GY

Distributed throughout Snake and Lewis 

rivers, other areas as noted on map.

Mountain Whitefish—MW

large 

scales

small mouth, 

no teeth body almost round 

on cross-section
18 

Cutthroat trout x rainbow trout hybridization

In waters where rainbow trout have 

been introduced, there has been a 

serious degradation of the cutthroat 

trout population through interbreeding. Presently, hybridized cutthroat 

trout exist throughout the Bechler, 

Falls, Gallatin, Gardner, and Lamar 

river drainages, and the Yellowstone 

River below the Upper Falls.

Hybrids will have characteristics 

consistent with both species, often 

making identification difficult. In the 

Yellowstone and Lamar rivers and 

tributaries in the Northeast Region of 

the park, rainbow trout and cutthroat

x rainbow trout hybrids have white 

tips on the anal and paired pelvic fins 

and must be killed. 

Combating hybridization

Once hybridization occurs, a cutthroat population can only be restored to genetic purity if all fish are 

removed from a stream and genetically pure cutthroat are reintroduced. 

To reduce hybridization in cutthroat 

trout habitat, anglers are encouraged 

to harvest nonnative trout in the 

Native Trout Conservation Area.

numerous 

spots on 

head

small scales

often white 

on edge of fins

Widely distributed due to historic 

stocking. Not present in Yellowstone Lake, 

Yellowstone River above the Upper Falls, 

or the Snake River.

Fish Identification—Nonnative

Rainbow Trout—RT

white tips on fins
19

worm-like markings

red spots with 

blue haloes

light spots, dark 

background

dark and light edge on fins

Widely distributed due to historic 

stocking. Not present in Yellowstone Lake, 

Yellowstone River above the Upper Falls, 

or the Gallatin River.

Brook Trout—BK

Fish Identification—Nonnative

Distributed in Gallatin, Gibbon, Firehole, 

Madison, Lewis, Snake, Gardner, and 

the Yellowstone rivers. Not present in 

Yellowstone Lake, Bechler or Falls rivers.

pale haloes

around black spots

Brown Trout—BN

©BIG SKY ANGLERS
20 

deeply 

forked 

tail

numerous 

spots on 

head

white spots, dark 

background

Fish Identification—Nonnative

Distributed in Heart, Lewis, Shoshone, and Yellowstone lakes.

Lake Trout—LT

often white 

on edge of fins

All lake trout MUST BE KILLED in Yellowstone Lake.

If you do not want to keep the fish, puncture the air bladder and drop it into 

water as deep as possible. In the backcountry, dispose of fish entrails and 

remains in fast moving or deep water. Do not discard trout carcasses along 

streams as they will attract bears.

air bladder

Smallmouth Bass—SB

hard spines on 

front of dorsal fin dark brown 

horizontal bars 

across head

pelvic fins are 

forward on body, 

below pectoral fins

yellowish-white 

underside

golden-olive and 

brown with dark 

brown vertical bars 

or splotches along 

the body

Smallmouth bass are a member of the Sunfish family of 

fishes which are not native to the park and are aggressive 

predators. Catchable smallmouth bass can be from 4 to 20 

or more inches long.

All smallmouth bass MUST BE KILLED parkwide.
21

Angler Etiquette

Yellowstone hosts tens of thousands 

of anglers each year, concentrated 

in just a few months. For your own 

enjoyment, the enjoyment of those 

around you, and the protection of 

our aquatic resources, please remember to be courteous and observe the 

following behavior. 

• Use established trails and avoid 

sensitive wetland vegetation such 

as bogs and seeps. Heavy trail use 

in these areas causes erosion and 

loss of habitat essential to many of 

Yellowstone’s wildlife. 

• Anglers must stay on established 

trails in thermal areas and must 

not cross these areas or approach 

thermal features.

• Avoid using the streambed as a 

pathway. Your footsteps can damage aquatic habitats and kill eggs 

and fry in the gravel.

• Do not overfish a good fishing 

area. Fish for a while, and then 

move on. 

• Do not encroach on another 

angler’s space and keep out of sight 

of other anglers, if possible.

• During late July and August, when 

water temperatures can be high, do 

most of your fishing early and late 

in the day. Allow fish to rest during 

the heat of the day.

These actions are illegal and 

destructive.

• Possessing a native cutthroat 

trout or any other native fish. 

• Releasing a nonnative fish 

alive within a mandatory kill 

area.

• Moving any live fish, water, 

sediment (mud), fish eggs, 

fish parts, or other aquatic 

animals or plants within the 

park—whether intentional 

or not.

• Bringing any aquatic invasive 

species, water, mud, plants, 

or bait (live or dead) into the 

park.

ä If you witness a violation please report it immediately to a law enforcement 

ranger, or call 307-344-7381 

and press “0” to immediately 

reach park dispatch.

Walking in stream beds can damage 

delicate aquatic habitats.
22 

Why are the same fish species 

regulated differently in different 

areas of the park?

Park fishing regulations are designed 

to protect native fish and aquatic 

ecosystems, provide recreational 

opportunities, and also preserve the 

tradition of angling in Yellowstone. 

Cutthroat trout, Arctic grayling, 

mountain whitefish, and other native 

fishes are important to the ecology 

of Yellowstone. Nonnative trout are 

important to the angler experience 

in Yellowstone, and angling is an 

important part of the park’s cultural 

history.

In Yellowstone, bald eagles, ospreys, pelicans, otters, grizzly bears, 

and other wildlife take precedence 

over humans in using fish for food. 

Park management and regulations 

reflect this priority. For example, 

some waters are closed to fishing to 

protect threatened and endangered 

species, and sensitive nesting birds. 

Regulations ban lead tackle because 

the lead concentrates in aquatic 

environments, posing a risk of lead 

poisoning to waterfowl that might 

ingest it. Only non-toxic alternatives 

to lead are allowed (see p. 3 for one 

exception). Of particular concern in 

Yellowstone are the alarmingly low 

populations of trumpeter swans and 

loons.

Yellowstone is making a substantial, 

on-the-ground effort to conserve 

native fish in several areas. These 

actions, which are currently focused 

in the Lamar and Grayling Creek 

drainages and Yellowstone Lake, are 

described in the park’s native fish 

conservation plan. The goals of the 

plan are to reduce the risk of extinction, restore and maintain the ecological role, and create sustainable 

angling and viewing opportunities for 

native fish.

Where did the nonnative fish 

come from?

When Yellowstone became a national 

park, more than 40 percent of its 

waters were barren of fish—including 

Shoshone Lake, Lewis Lake, and the 

Firehole River above Firehole Falls. 

Early park managers transplanted fish 

into new locations, produced more 

fish in hatcheries, and introduced 

Frequently Asked Questions

Early park managers transplanted fish to 

stock the park’s fishless waters.

Fishing is a long-standing tradition in 

Yellowstone’s waters.
23

nonnative species. By the mid-20th 

century, more than 310 million fish 

had been stocked in the park. 

The ranges and densities of the park’s 

native fish species have been substantially altered during the past century, 

mostly because of introduced nonnative fish. 

What are the ecological impacts 

of cutthroat trout conservation?

Cutthroat trout are the sole native 

trout of Yellowstone National Park 

and were the dominant fish species here prior to Euroamerican 

settlement. 

Because cutthroat trout inhabit relatively shallow waters, many animals 

depend on them as a food source, 

especially during spring when the 

cutthroat are spawning in small inlets 

and tributary streams. In many cases, 

nonnative fish cannot serve as a 

substitute for cutthroat trout because they occupy different habitats. 

For example, lake trout live deep in 

Yellowstone Lake and are not generally accessible to the park’s native 

fish-eating animals. 

Preserving cutthroat trout will help 

preserve all of the animals that 

depend upon them as a food source; 

ensure visitors can continue to see 

them spawning near Fishing Bridge, 

LeHardys Rapids, and other places; 

and make sure future generations will 

be able to experience them by angling 

in the many wild, scenic waters the 

park has to offer.

Frequently Asked Questions

Why can’t we fish from 

Fishing Bridge?

Fishing Bridge, situated over 

a cutthroat trout spawning 

area, was once a popular place 

to fish. Declining numbers of 

cutthroat trout caused park 

officials to close the bridge to 

fishing to protect the spawning 

fish.

Cutthroat trout are the sole native trout 

of Yellowstone National Park.

More than sixteen species depend on 

cutthroat trout as a food source.
24 

Glossary

Artificial Fly—a hook, in which a 

minimum of half the shank of the 

hook is dressed with conventional 

natural or synthetic material in a 

common method known as fly tying. 

This includes dry flies, wet flies, 

streamers, egg patterns, and nymphs. 

Hair, feathers, metallic colored tape, 

tinsel, mylar, bead eyes, dumbbell 

eyes, beads (metal, glass or plastic), 

foam, rubber and lead-free metal 

wire, tape or body wrap may be used 

as an integral part of the design and 

fly pattern. 

Artificial Lure—a man-made or 

artificial device, complete with a 

hook, intended to attract and entice 

a fish for the purpose of taking them; 

excludes artificial flies and attractors. 

Attractor—a hook-less device attached to a fishing line between the 

end of a rod and an artificial fly or artificial lure or that provides additional motion or other visual attraction. 

Typical attractors include but are not 

limited to dodgers, lake trolls, such as 

Ford fenders, willow leaf, or cowbell 

flashers, artificial rubber or molded 

plastic (soft or hard beads). 

A strike indicator is not considered 

an attractor. 

Bait—all dead or live organisms or edible parts thereof; natural or artificial 

food or products thereof; chemically 

treated or processed fish eggs or animal products; artificial dough, paste 

or edible lures; and rubber worms, 

rubber leeches, or twister tails. This 

definition does not apply to hair or 

feathers used as fly-tying material. 

Barbless Hook—a hook manufactured without a barb or a hook on 

which barbs have been filed off, 

closed (point of the barb has been 

crimped or pinched so the barb 

touches the hook shank), or has otherwise been completely removed. 

Catch-and-Release—a fish must be 

carefully and immediately returned 

alive to the water from which it was 

caught.

Closely Attended—a person fishing 

must be able to immediately control 

their line or rod at all times in order 

to react to a potential strike. 

Drainage—the stream proper and 

area of land which includes all 

streams, lakes and tributaries that 

drain into that stream.

Dropper—an artificial fly being used 

as a second artificial fly on a two 

artificial fly rig. A dropper is commonly attached to a primary fishing 

line or artificial fly by means of tippet 

or other fishing line.

Fly Fishing—artificial flies may only 

be attached to a line for the purpose 

of attracting and enticing fish for 

take, regardless of the type of rod or 

line used. 

©JAMES MARSH
25

Glossary

Hook—a bent wire device, for catching fish, to which a single, double or 

treble point is attached to a single 

shank.

• Single Point: a hook with only one 

point.

• Double Point: a hook with two 

points on a common shank.

• Treble (triple) Point: a hook with 

three points on a common shank. 

Invasive (nonnative) Species—a 

species that:

• Does not naturally occur or is 

alien to the ecosystem under 

consideration.

• Cause, or are likely to cause, economic or environmental harm or 

harm to human health.

• Invasive species can be plants, 

animals, and other organisms (e.g. 

microbes).

Lake—a body of standing water in a 

depression of land and includes reservoirs and ponds (excluding ponds 

created by beavers). 

Scented Attractants—any substance 

that has been added, infused or 

applied to an artificial fly, artificial 

lure, line, or hook for the purpose 

of attracting fish by scent; excludes 

non-scented materials or chemicals 

specifically designed and produced 

to cause flies to float or sink.

Snagging—taking or attempting to 

take a fish by the use of an artificial 

fly or artificial lure in any manner or 

method that the fish does not voluntarily take the hook in its mouth. 

Fishing only by means of a bare hook 

that is not an artificial fly or artificial 

lure, regardless of manner or method, will be considered snagging. 

Stream—water in a permanent or 

seasonal bed or channel with a current that is usually continuous in one 

direction and includes creeks, rivers, 

ditches, sloughs and ponds created 

by beavers. Streams may not flow 

continuously during low-flow periods. Ponds or puddles in a stream 

channel during low-flow periods 

shall be considered to be a stream. 

Strike indicator—a hook-less, unscented floating device attached to a 

line or leader to signal a strike at an 

artificial fly or artificial lure. 

Tributary—a stream that flows into a 

larger stream, river or lake. 

Upgrading—the practice of substituting captured fish for fish in 

possession.

Yellowstone Native Fish Species—a 

species that is endemic or indigenous 

to Yellowstone National Park. 
For More Information

If you have questions about information in this guide, please contact:

Visitor Services Office

P.O. Box 168

Yellowstone National Park, WY 82190

307-344-2107

For more information about Yellowstone fisheries, go to:

www.nps.gov/yell/planyourvisit/fishing.htm

All maps and photos are NPS (public domain) except: 

Pages 16,17, and 19 ©Jay Fleming Photography.

Page 3, ©New South Wales Department of Trade and Investment, Regional 

Infrastructure and Services.

Page 17, mountain whitefish ©Zac Sexton.

Page 19, brown trout ©Big Sky Anglers.

Page 24, “Perfect Fly” salmon fly ©James Marsh.