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M. R. Campbell

Publications and source records attributed to M. R. Campbell.

15 recordsLinked to original sources
USGS2011

Genetic variation in westslope cutthroat trout Oncorhynchusclarkii lewisi : implications for conservation

Twenty-five populations of westslope cutthroat trout from throughout their native range were genotyped at 20 microsatellite loci to describe the genetic structure of westslope cutthroat trout. The most genetic diversity (heterozygosity, allelic richness, and private alleles) existed in populations from the Snake River drainage, while populations from the Missouri River drainage had the least. Neighbor-joining trees grouped populations according to major river drainages. A great amount of genetic differentiation was present among and within all drainages. Based on Nei’s DS, populations in the Snake River were the most differentiated, while populations in the Missouri River were the least. This pattern of differentiation is consistent with a history of sequential founding events through which westslope cutthroat trout may have experienced a genetic bottleneck as they colonized each river basin from the Snake to the Clark Fork to the Missouri river. These data should serve as a starting point for a discussion on management units and possible distinct population segments. Given the current threats to the persistence of westslope cutthroat trout, and the substantial genetic differentiation between populations, these topics warrant attention.

Idaho, Montana↗
USGS1906

Report on the operations of the coal-testing plant of the United States Geological Survey at the Louisiana Purchase Exposition, Saint Louis, Missouri, 1904: Part I.--Field work, classification of coals, chemical work

The authority for conducting at the Louisiana Purchase Exposition an investigation of the coals and lignites of the United States is contained in the act of Congress providing for the urgent deficiencies in the appropriations for the fiscal year 1905, and approved February 18, 1904, as follows: For analyzing and testing. at the Louisiana Purchase Exposition the coals and lignites of the United States, in order to determine their fuel values mid the most economical method for their utilization for different purposes, under the supervision of the Director of the United States Geological Survey, thirty thousand dollars, to be available until expended: Provided, That all testing machinery and all coals and lignites to be tested shall be contributed without charge to the Government. In the general deficiency bill approved April 27, 1904, an additional appropriation of $30,000 was provided, making the total sum appropriated for this work $60,000. For carrying out the provisions of these acts the Director of the Geological Survey appointed a committee, consisting of Edward W. Parker, Joseph A. Holmes, and Marius R. Campbell, to direct the construction and operation of the plant. It will be observed that under the law authorizing this work all of the testing machinery and all of the coals to be tested had to be furnished to the Government free of charge. Under these conditions it was not possible to equip an ideal testing plant, and the assembling and construction of such equipment as conld be obtained under these provisions entailed some annoying delays in the completion of the plant. In addition to this, the delivery of a considerable quantity of operating and conveying apparatus purchased from the Link Belt Machinery Company, of Chicago, was delayed by a strike in the works of that company. As a result of these combined influences the plant was not put in operation until the 1st of September. Notwithstanding these delays, the committee feels that through the hearty and patriotic cooperation of a large number of manufacturers of apparatus and machinery it was able to collect and install, within a notably short time, a testing plant that was well suited for such pioneer work.

Missouri↗