Changes in Distribution of Trout in Great Smoky Mountains National Park, 1900-1977
Changes in Distribution of Trout in Great Smoky Mountains National Park, 1900-1977

Author: George Alan Kelly

Publisher:

Published: 1980

Total Pages: 16

ISBN-13:

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Significant changes have occurred in the distribution of trout in streams of Great Smoky Mountains National Park since 1900. By the mid-1970's the original range of the native brook trout had been reduced by about 70% and the species was relegated to suboptimal habitat in head water streams. Most of the stream sections lost by brook trout became the territory of the introduced rainbow trout, which in 1977 occupied about 80% of the Park waters. After 1950, brown trout introduced in State waters outside the Park established reproducing populations in some 50 miles of stream formerly occupied only by rainbow trout. If current trends continue, the recovery of brook trout in Park water may be difficult, if not impossible, and brown trout may occupy much of the territory now held by rainbow trout.

Proximate Composition and Caloric Content of Eight Lake Michigan Fishes
Proximate Composition and Caloric Content of Eight Lake Michigan Fishes

Author: Donald V. Rottiers

Publisher:

Published: 1982

Total Pages: 16

ISBN-13:

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The proximate composition (percentage lipid, water, fat-free dry material, ash) and caloric content of eight species of Lake Michigan fish were measured: lake trout, coho salmon, lake whitefish, bloater, alewife, rainbow smelt, deepwater sculpin, and slimy sculpin. Except for alewives, proximate composition and caloric content did not differ significantly between males and females. Although the caloric content of all species varied directly with lipid content and inversely with water content, an increase in lipid content did not always coincide with a proportional increasein caloric content when other components of fish composition were essentially unchanged. This observation suggests that the energy content of fish estimated from the proximate composition by using universal conversion factors may not necessarily be accurate.

Acute Toxicity of Six Forest Insecticides to Three Aquatic Invertebrates and Four Fishes
Acute Toxicity of Six Forest Insecticides to Three Aquatic Invertebrates and Four Fishes

Author: Herman O. Sanders

Publisher:

Published: 1983

Total Pages: 12

ISBN-13:

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Technical grade and field formulations of six experimental forest insecticides -- methomyl, carbaryl, aminocarb, trichlorfon, fenitrothion, and acephate -- were tested for acut toxicity against three species of aquatic invertebrates, (a daphnid, an amphipod, and larvae of a midge), and four species of fish (bluegill, rainbow trout, fathead minnow, channel catfish). Five of the six insecticides were highly toxic or extremely toxic to the daphnid, amphipod, and midge larvae. The sixth insecticide, acephate, was not toxic to invertebrates at concentrations up to 50 mg/L. Five of the insecticides ranged from highly toxic (methomyl to channel catfish) to relatively non-toxic (trichlorfon to fathead minnows); the sixth, acephate, was only slightly toxic to the fishes tested.