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- ›Micropterus dolomieu

Smallmouth Bass
Micropterus dolomieu
The smallmouth bass (Micropterus dolomieu) is a species of freshwater fish in the sunfish family (Centrarchidae) of the order Centrarchiformes. It is the type species of its genus Micropterus (black basses), and is a popular game fish sought by anglers throughout the temperate zones of North America, and has been spread by stocking —as well as illegal introductions—to many cool-water tributaries and lakes in Canada and more so introduced in the United States. The maximum recorded size is approximately 27 inches (69 cm) and 12 pounds (5.4 kg).
The smallmouth bass is native to the upper and middle Mississippi River basin, the Saint Lawrence River–Great Lakes system, the Champlain Valley, and the Hudson Bay basin. Its common names include smallmouth, bronzeback, brown bass, brownie, smallie, bronze bass, and bareback bass.
From the article Smallmouth bass on Wikipedia (CC BY-SA), quoted section by section
Description
Smallmouth have a slender but muscular fusiform body shape making them powerful swimmers. The coloration of the smallmouth bass's ctenoid scales range from golden-olive to dark brown dorsally which fades to a yellowish white ventrally with dark brown vertical bars or blotches along the body and dark brown horizontal bars on the head. The combination of the muscular fusiform body shape and camouflage like coloring make these fish highly effective ambush predators. The coloration can vary greatly depending on the fishes age, habitat, water quality, diet, and the spawning cycle. Generally, the protruding jaw of the smallmouth does not extend back beyond the eyes which are red or brown. They have two dorsal fins which are separated by a shallow interdorsal notch. The front dorsal has 9–11 spiney rays and the back dorsal has 13–15 soft rays. Males are generally smaller than females. The males tend to range around two pounds, while females can range from three to six pounds. Their average sizes and coloration can differ, depending on if they are found in lacustrine or riverine habitats. …
Range & habitat
The smallmouth bass is found in clearer water than the largemouth, especially streams, rivers, and the rocky areas and stumps and also sandy bottoms of lakes and reservoirs. It can also survive in a stronger current than other black bass. The smallmouth prefers cooler water temperatures than its cousin the largemouth bass, and as a result will often seek out deeper, faster moving water during the hot summer months. Because it is intolerant of pollution, the smallmouth bass is a good natural indicator of a healthy environment, though they are still much more resilient than most trout species. Carnivorous, its diet comprises crayfish, amphibians, insects, and smaller fish, while the larvae feed on various zooplankton and insect larvae. Adults also cannibalize young of other parents.
The female can lay up to 21,100 eggs, which are guarded by the male in his nest.
Wikipedia: “Habitat”
Where it lives
Recorded sightings
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geo-referenced records in GBIF, from museums, herbaria and field observers.
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In the stacks
Searching the stacks…
Every page naming Micropterus dolomieu in the Biodiversity Heritage Library →
This page is assembled live from iNaturalist, GBIF, Wikipedia, the Source Library and the Internet Archive. It is not yet part of the hand-edited codex. iNaturalist taxon 49590.