Fish Identification on the Niagara River

Smallmouth bass show a jaw hinge that stops under the eye, a shallow notch between the dorsal fins and a bronze flank that turns olive over rock. Walleye show a white lower lobe on the tail, a spiny front dorsal and a milky eye that reflects light. Salmon and trout separate by the mouth line, the tail shape and the spotting pattern, not by colour alone.

How can I identify smallmouth bass in the Niagara River?

Start with the jaw. On a smallmouth bass the upper jaw reaches back to a point level with the middle or rear of the eye, and no further. On a largemouth bass the same line runs well past the eye. That single measurement settles most of the fish a shore angler lifts out of the Niagara.

Then look at the back. The dorsal fin is split into two parts: a spiny front section and a soft rear section, joined by a shallow dip. The dip is not deep. Largemouth bass carry a much deeper notch at the same place.

Colour is the least reliable mark. A smallmouth over Niagara rock reads bronze to brown, sometimes near black in deep shade, and it pales to olive or yellow over sand and gravel. Fish in the lower river often look darker than fish in the upper river for no reason other than bottom type and light.

Three marks confirm the call at the boat or on the bank:

• Jaw hinge level with the eye, never past it.
• Shallow notch between the two dorsal sections.
• Rows of dark spots along the lower flank, faint on some fish, clear on others.

Habitat narrows it further. Smallmouth bass hold over rock, rubble and current breaks, and they sit deeper and tighter to structure than largemouth. In the Niagara they are a fish of moving water and hard bottom, and a fish caught over weed and mud is worth a second look at the jaw.

Season changes the picture. In spring and early summer they push shallow and feed hard; by late summer they slide to deeper rock and the light drops off fast. A field guide that keeps species, depth and season in one place is worth carrying, and the species notes at Niagara River fish identification cover the same ground for both banks.

How can I identify walleye in the Niagara River?

Go to the tail first. A walleye has a white tip on the lower lobe of the caudal fin, and on most Niagara fish that patch is unmistakable. It is the fastest single check on the list.

Next, the eye. The eye is large, and a layer behind the retina throws light back, so a walleye in a lamp beam or in daylight at the right angle shows a milky glow. That is why the fish feeds in low light and why anglers meet it at dusk and after dark.

Then the fins. The front dorsal is spiny and the rear dorsal is soft, and the two are separated by a clear gap. The anal fin carries two or three spines at the front. The body is long, the mouth is large and the lower jaw juts slightly forward.

Colour runs olive to gold, mottled over the back, with a pale belly. The dark blotches on the flank are uneven and do not form the clean vertical bars seen on some other species. A walleye in cold water looks washed out; a walleye in warm shallow water looks darker and more golden.

Where does it sit? Over gravel, rubble and current seams, often within a metre of the bottom, and often in the last hour of light. In the upper river and the lower gorge the same pattern holds: hard bottom, moving water, dim light.

How can I tell salmon and trout apart in the Niagara River?

The mouth line is the first cut. On a trout the upper jaw reaches back past the eye. On a Pacific salmon it stops short of the rear of the eye. That rule holds on most adults in the river, though it is harder to read on small fish.

Then the tail. Adult salmon, chinook and coho alike, carry a slightly forked tail. Trout, brown and rainbow, carry a square or slightly convex tail. On a fresh fish the difference is plain; on a spawned out fish it is worn and less useful.

Spotting helps. Brown trout show dark spots on a pale body, with red or orange spots mixed in and often a pale halo around them. Rainbow trout show small black spots over the back and tail, and a pink to red stripe along the flank on fresh fish. Chinook salmon show black spots on the back and on both lobes of the tail, with a black mouth line. Coho salmon show black spots on the back and upper tail lobe only, and the lower jaw of a spawning male turns deep red.

Gums and mouth colour are a last check. A chinook has a black mouth and black gums at the base of the teeth. A coho has a black mouth with a paler gum line. Brown trout have a pale mouth. None of these marks is perfect on a fish that has been in the river for weeks, so use two or three together.

What changes the read on the water?

Light is the first variable. A fish in flat light loses contrast and the jaw line and spots go soft. A fish in direct sun shows colour well but blows out the pale marks. Overcast, or the last hour before dark, is the best light for identification, and it is also when walleye move.

Depth is the second. A fish held deep in the water column reads grey and loses its pattern. Lift it clear of the surface, or look at it through a polarised lens at close range, before you commit to a species.

Season is the third. Spawning colour changes the rules. Male coho turn red on the lower jaw, brown trout grow a hooked jaw, and rainbow trout lose the clean stripe. A mark that is reliable in July can fail in October.

Water clarity matters too. The Niagara runs clear in the upper river and carries more colour below the falls. In coloured water, silhouette and fin shape beat colour every time. The document read beside this page is the New York State fishing pages.