Stock Characteristics and Habitat Use of Catfishes in Regulated Sections of 4 Alabama Rivers

We sampled 3 species of catfish (blue catfish Ictalurus furcatus, channel catfish I. punctatus, and flathead catfish Pylodictis olivaris) from 3 different habitat types (tailrace, main channel, tributary) in 4 river systems in Alabama to quantify their relative distribution, age structure, growth, and habitat use. Blue and flathead catfish were more abundant than channel catfish in all systems, and flathead catfish were both most numerous and had the greatest average length in 3 of the 4 systems. Blue and flathead catfish had similar age distributions containing both juveniles and adults, while channel catfish were dominated by young and immature fish. Flathead catfish abundance did not differ across habitat types, although they tended to be found near woody debris and in higher flow. Blue catfish catch rates did not differ among habitats, although their abundance tended to be higher in pebble/cobble substrates. Channel catfish catch rates similarly did not differ across habitat types, but they were significantly more abundant in samples with higher flows and clearer water. Growth rates were highest for flathead catfish in 3 of the 4 systems, followed by blue catfish and channel catfish. When compared to growth rates observed in other states, flathead catfish grew more slowly in Alabama, while channel and blue catfish grew at similar rates as observed elsewhere. Both flow and the presence of woody debris in tailraces appear important to the coexistence of these species in Alabama's waters.

Starting page
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Ending page
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ID
11982