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Geology topics

Carl L. Armour

Publications and source records attributed to Carl L. Armour.

13 recordsLinked to original sources

Evaluating temperature regimes for protection of brown trout

Geographic distribution and population success of brown trout (Salmo trutta) are affected by temperature regimes. Concepts are presented for evaluating alternative temperature regimes for brown trout based on published temperature information and professional judgment. Temperature information from the literature is included for spawning runs, spawning, egg and larval development, growth, and other subjects. The objective is to aid biologists in evaluating alternative temperature regimes so as to select those that will protect and enhance environmental quality for brown trout.

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Evaluating temperature regimes for protection of Smallmouth Bass

The success of smallmouth bass (Micropterus dolomieu) is affected by temperature regimes. Concepts are presented for evaluating the suitability of alternative temperature regimes through experimentally derived data, including ultimate incipient lethal temperatures and maximum weekly average, short-term maximum, and final preferendum temperatures. Also, concepts are described for basing evaluations on temperature tolerances for periods including spawning, egg and larval incubation, growth, and winter survival in the first year of life.

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Group decision-making techniques for natural resource management applications

This report is an introduction to decision analysis and problem-solving techniques for professionals in natural resource management. Although these managers are often called upon to make complex decisions, their training in the natural sciences seldom provides exposure to the decision-making tools developed in management science. Our purpose is to being to fill this gap. We present a general analysis of the pitfalls of group problem solving, and suggestions for improved interactions followed by the specific techniques. Selected techniques are illustrated. The material is easy to understand and apply without previous training or excessive study and is applicable to natural resource management issues.

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Evaluation of the instream flow incremental methodology by U.S. Fish and Wildlife Service field users

This paper summarizes results of a survey conducted in 1988 of 57 U.S. Fish and Wildlife Service field offices. The purpose was to document opinions of biologists experienced in applying the Instream Flow Incremental Methodology (IFIM). Responses were received from 35 offices where 616 IFIM applications were reported. The existence of six monitoring studies designed to evaluate the adequacy of flows provided at sites was confirmed. The two principal categories reported as stumbling blocks to the successful application of IFIM were beliefs that the methodology is technically too simplistic or that it is too complex to apply. Recommendations receiving the highest scores for future initiatives to enhance IFIM use were (1) training and workshops for field biologists; and (2) improving suitability index (SI) curves and computer models, and evaluating the relationship of weighted useable area (WUA) to fish responses. The authors concur that emphasis for research should be on addressing technical concerns about SI curves and WUA.

Fisheries

Guidance for evaluating and recommending temperature regimes to protect fish

Procedures are presented for evaluating temperature regimes for fish. Although examples pertain to spring chinook salmon ( Oncorhynchus tshawytscha ), the principles apply to other species. Basic temperature tolerance relationships for fish are explained and three options are described for comparing alternative temperature regimes. The options are to base comparisons on experimental temperature tolerance results, suitability of a simulated temperature regime for key life stages, or population statistics and predicated responses to simulated temperatures.

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Guidance for modeling causes and effects in environmental problem solving

Environmental problems are difficult to solve because their causes and effects are not easily understood. When attempts are made to analyze causes and effects, the principal challenge is organization of information into a framework that is logical, technically defensible, and easy to understand and communicate. When decisionmakers attempt to solve complex problems before an adequate cause and effect analysis is performed there are serious risks. These risks include: greater reliance on subjective reasoning, lessened chance for scoping an effective problem solving approach, impaired recognition of the need for supplemental information to attain understanding, increased chance for making unsound decisions, and lessened chance for gaining approval and financial support for a program/ Cause and effect relationships can be modeled. This type of modeling has been applied to various environmental problems, including cumulative impact assessment (Dames and Moore 1981; Meehan and Weber 1985; Williamson et al. 1987; Raley et al. 1988) and evaluation of effects of quarrying (Sheate 1986). This guidance for field users was written because of the current interest in documenting cause-effect logic as a part of ecological problem solving. Principal literature sources relating to the modeling approach are: Riggs and Inouye (1975a, b), Erickson (1981), and United States Office of Personnel Management (1986).

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