Lake chub
Encyclopedia
The Lake Chub, Couesius plumbeus, is a freshwater
cyprinid
fish
found in Canada
and in parts of the United States
. Of all North America
n minnows, it is the one with the northernmost distribution. Its genus
, Couesius (after Dr. Elliott Coues
, who collected the holotype
specimen), is considered monotypic
today.
and Utah.
, insects, aquatic insect larvae, and algae. The largest individuals can capture small fishes. The lake chub itself can be eaten by large predatory fishes and is therefore suitable as bait for fishing.
s that are among the most precise of the few fish species studied to date. These fish are usually diurnal in the laboratory, but in the wild they can be diurnal, crepuscular, or nocturnal.
The lake chub has large optic lobes in its brain and is therefore presumed to be a good sight feeder. It can, however, feed at night also. Comparisons with other freshwater fishes such as stickleback
, northern pike
, sculpin
, and burbot
have revealed that it has a superior hearing capacity.
) species living in Lake Michigan, which are often called Michigan Lake chubs.
The lake chub is sometimes called by other names such as northern chub, lake northern chub, chub minnow, plumbeus minnow, or bottlefish. The species is also found in Quebec and its French name is "mené de lac".
Freshwater
Fresh water is naturally occurring water on the Earth's surface in ice sheets, ice caps, glaciers, bogs, ponds, lakes, rivers and streams, and underground as groundwater in aquifers and underground streams. Fresh water is generally characterized by having low concentrations of dissolved salts and...
cyprinid
Cyprinid
The family Cyprinidae, from the Ancient Greek kyprînos , consists of the carps, the true minnows, and their relatives . Commonly called the carp family or the minnow family, its members are also known as cyprinids...
fish
Fish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...
found in Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
and in parts of the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. Of all North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
n minnows, it is the one with the northernmost distribution. Its genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
, Couesius (after Dr. Elliott Coues
Elliott Coues
Elliott Coues was an American army surgeon, historian, ornithologist and author.Coues was born in Portsmouth, New Hampshire. He graduated at Columbian University, Washington, D.C., in 1861, and at the Medical school of that institution in 1863...
, who collected the holotype
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...
specimen), is considered monotypic
Monotypic
In biology, a monotypic taxon is a taxonomic group with only one biological type. The term's usage differs slightly between botany and zoology. The term monotypic has a separate use in conservation biology, monotypic habitat, regarding species habitat conversion eliminating biodiversity and...
today.
Description
The body is elongate, usually 100 mm (4 in) long, though some individuals twice that length have been found. The back is olive-brown or dark brown, and the sides are leaden silver, hence the word plumbeus, referring to lead, in the scientific name of this fish. The snout is blunt and projects slightly beyond the upper lip. The corners of the mouth each bear a small barbel. The scales are small but well visible, and some may be black and form isolated dark spots on the lower sides. The dorsal, pelvic and anal fins each have 8 rays. The pectoral fins are broad and have 13-18, but more usually 15-16, rays. Breeding males can develop patches of bright orange or red at the base of the pectoral fins and sometimes near the mouth, and small nuptial tubercles on the top of the head, dorsal surface of pectoral rays, and on the belly near the base of the pectorals.Distribution
The lake chub is generally found throughout Canada up to the Arctic Circle. Some scattered populations are also present in the northern United States, more precisely in New England, Michigan, Iowa, Wisconsin, Minnesota, the Dakotas, Montana, Wyoming, Colorado, Washington, Idahoand Utah.
Habitat
As its common name implies, the lake chub is most commonly found in lakes, but it can also live in rivers and streams. In mid-summer it may move to the deeper parts of a lake to avoid the warmer waters of the lake shore.Diet
The diet of the lake chub is varied: zooplanktonZooplankton
Zooplankton are heterotrophic plankton. Plankton are organisms drifting in oceans, seas, and bodies of fresh water. The word "zooplankton" is derived from the Greek zoon , meaning "animal", and , meaning "wanderer" or "drifter"...
, insects, aquatic insect larvae, and algae. The largest individuals can capture small fishes. The lake chub itself can be eaten by large predatory fishes and is therefore suitable as bait for fishing.
Growth
In and around Catamaran Brook, New Brunswick, Canada, lake chubs over 5 cm long (2 inches) were found to grow by about 0.8 cm (0.3 inch) a month in summer.Reproduction
Lake chubs normally undergo spawning migrations in early summer. Temperature plays a role in triggering migration onset, as migrations are delayed on colder years. Migrating chubs leave their lakes and rivers to ascend tributary streams, in which they mate (by day or night) and release their eggs over gravel or rocks. There is no parental care. During migration the fish move mostly during dusk and at night.Behaviour
In the laboratory, lake chubs have expressed free-running circadian rhythmCircadian rhythm
A circadian rhythm, popularly referred to as body clock, is an endogenously driven , roughly 24-hour cycle in biochemical, physiological, or behavioural processes. Circadian rhythms have been widely observed in plants, animals, fungi and cyanobacteria...
s that are among the most precise of the few fish species studied to date. These fish are usually diurnal in the laboratory, but in the wild they can be diurnal, crepuscular, or nocturnal.
The lake chub has large optic lobes in its brain and is therefore presumed to be a good sight feeder. It can, however, feed at night also. Comparisons with other freshwater fishes such as stickleback
Stickleback
The Gasterosteidae are a family of fish including the sticklebacks. FishBase currently recognises sixteen species in the family, grouped in five genera. However several of the species have a number of recognised subspecies, and the taxonomy of the family is thought to be in need of revision...
, northern pike
Northern Pike
The northern pike , is a species of carnivorous fish of the genus Esox...
, sculpin
Sculpin
A Sculpin is a fish that belongs to the order Scorpaeniformes, suborder Cottoidei and superfamily Cottoidea, that contains 11 families, 149 genera, and 756 species...
, and burbot
Burbot
The burbot is the only gadiform fish inhabiting freshwaters. It is also known as mariah, the lawyer, and eelpout. It is closely related to the marine common ling and the cusk...
have revealed that it has a superior hearing capacity.
Common name
The lake chub must not be confused with various cisco (genus CoregonusCoregonus
Coregonus is a diverse genus of fish in the salmon family . The type species is the common whitefish . The Coregonus species are known as whitefishes...
) species living in Lake Michigan, which are often called Michigan Lake chubs.
The lake chub is sometimes called by other names such as northern chub, lake northern chub, chub minnow, plumbeus minnow, or bottlefish. The species is also found in Quebec and its French name is "mené de lac".