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<br />
<br />Habitat
<br />
<br />This large sucker is an inhabitant of large rivers and has ad-
<br />justed well to the impoundments of the lower Colorado River Basin.
<br />It commonly occurs at depths of four to eight feet over a bottom of
<br />sand, mud, or rock. Vegetation is sparse or lacking and water temper-
<br />atures are moderate to warm. The water may be silty, muddy or clear
<br />and the current, except in the artificial reservoirs, is usually strong
<br />where the adults are taken. The young occur in shallows at the
<br />river or reservoir margins where individuals approximately an inch
<br />long travel in schools numbering thousands. Over 6,000 specimens,
<br />10 to 35 mm. in standard length, were taken in two hauls of a
<br />10 x 16 minnow seine at the margin of the Colorado River, in
<br />Nevada, on June 15, 1950. Here the temperature was 710 to 760 F.,
<br />whereas the adjacent river was only 580.
<br />
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<br />
<br />CATFISH FAMILY
<br />
<br />'eta'uridae
<br />
<br />
<br />I
<br />
<br />This family of catfishes comprlsesfreshwater fishes known only
<br />from North America, ranging from southem Canada east of the
<br />" Rockies and southward to Guatemala. They include about 35 species,
<br />all of them scaleless and with a spinous ray at the front of the
<br />dorsal fin and one in each pectoral fin. These spines are capable
<br />of inflicting painful wounds. Catfishes are further characterized by
<br />the whisker-like barbels about the head and by the presence of
<br />an adipose fin on the back.
<br />
<br />Catfishes in general are a numerous, widespread group, repre-
<br />sented by many families and species, especially in South America
<br />and Asia. They occur on all continents and also in brackish lagoons
<br />and coastal salt waters. Some species, for example, the madtoms of
<br />eastem United States, rarely exceed six inches, but the flathead
<br />catfish of the Mississippi reaches a length up to five feet and
<br />a weight of more than 100 pounds; channel catfish three feet long
<br />may weigh 25 pounds. All of the largei' species are excellent eating,
<br />the flesh being white and firm.
<br />
<br />JOB
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