Name: Catastomus platyrhynchus - Mountain Sucker
Family: Catastomidae (Suckers)
Order:
Cypriniformes
(Suckers and Minnows)
Class: Osteichthyes (Bony Fishes)
Abundance: Patchy
Origin:
Native.
Active Season: Year Round
Size:
- average: 5 inches
- largest: 9 inches
Colors: green (upper side), white-gray (underside)
General Description: Mountain Suckers are a small river sucker found throughout the western United States, but limited in Montana to drainages east of the Continental Divide. They inhabit cold and clear mountain streams and medium-sized rivers. They have a typical sucker physique with a fleshy inferior mouth and countershaded coloration.
Similar Species:
It is usually quite difficult for expert fisheries ecologists to identify sculpins, unless a good dichotimous key is used. There are four species of sculpins in Montana. If you catch a sculpin East of the Continental Divide, it is most likely a mottled sculpin. Please note, however, there are spoonhead sculpins in the Waterton and St. Mary's drainages on the East side of Glacier National Park.
Life History: Mountain Suckers spawn early summer. They broadcast their eggs over riffle gravels in the vicinity of pools. Males reach maturity at age 2-4 with a maximum life span of 7 years. Females reproduce at age 3-5 with a maximum life span of 9 years.
Distribution: Mottle Sculpins are widely distributed throughout the United States, but are not found in the central states. In Montana, mottled sculpins are widely distributed and common in mountain streams east of the continental divide. They also have limited distribution in the Columbia River and Saskatchewan River drainages.
Habitat Description: Primarily inhabits riffle habitats in small to medium clear streams. Rarely found in lakes. Juvenile fish primarily utilize backwater areas.
Feeding Habits: Mountain suckers feed primarily on diatoms (algae), but they also eat insect larvae.
Enemies & Diseases: Mountain suckers are susceptible to predation by larger fishes, ospreys, otters, and other animals that commonly eat fish.
Did You Know: Mountain suckers are the smallest sucker in Montana. They were first noted by the Lewis and Clark Expedition on July 16, 1806 near Livingston, Montana.
Glossary:
- Countershaded Coloration: Animals have dark coloration on their backs to camouflage them against the bottom of a stream or lake, but they have light coloration on their underside to camoflage them against the sky from predators looking up from the bottom of a stream.
- Inferior Mouth: Mouth is on the underside of the head to facilitate feeding from the bottom of a stream or lake.
Contributor:
Matthew Corsi
ECOS is supported by the GK-12 Program of the National Science Foundation.