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A team from the U.S. Geological Survey studies the surface effects of the Oct. 1980 10 shock, whose epicenter was west of Algiers, near the African Plate boundary. -Authors...

Monoclinic calcium-poor shear-transformation lamellae and calcium-rich exsolution lamellae occur parallel to (100) in orthopyroxene. The formation of both structures from an orthopyroxene host involves a shear on (100) parallel to [001], with additional cation exchange in the exsolution case. The shear transformation involves a macroscopic simple shear angle of 13.3??...

Mallard (Anas platyrhynchos) populations breeding in temperate North America obtain a significant part of the energy and lipid requirements of reproduction at sites occupied prior to arrival on the breeding grounds. Protein for egg formation, however, is obtained principally from the diet during the nesting period. Both sexes arrive heavy...

Groups of sea lamprey (Petromyzon marinus) eggs fertilized by males previously immersed in an aqueous solution of p,p-bis(1-aziridinyl)-N-methylphosphinothioic amide (bisazir) at concentrations of 10–100 mg/L produced fewer normal, live prolarvae after 15–17 d of incubation than did groups of eggs fertilized by normal males. Mortality of embryos or prolarvae was nearly 100% in...

Although few biological data exist on the now extinct native lake trout, Salvelinus namaycush, of Lake Michigan, historical records and interviews with former commercial fishermen strongly suggest that this once widespread resource was composed of a number of discrete spawning populations or stocks. A natural division of the resource into distinct...

A conventional 35-mm camera equipped with an f2.8 135-mm lens and ASA 64 color film was used to acquire sex ratio data on mallards (Anas platyrhynchos) wintering in the Platte River Valley of south-central Nebraska. Prelight focusing for a distance of 30.5 metres and setting of shutter speed at 1/2000...

No abstract available....

Wetland characteristics were assessed from a systematic sample of 66 plots, 3.22 km2 each, drawn from a 10,041-km2 study area in central North Dakota. Each plot was visited once and 8 sets of aerial photographs were obtained in 3 years. Density of wetland basins was 11.00 ha/km2, and area averaged...

To determine how much organic nitrogen is lost from lakes during winter by natural processes, we collected water in fall and winter from six small lakes (area, 5-822 hectares) and separated organic matter dissolved in the water with n-butanol into three fractions--yellow organic acids, a white precipitate, and aqueous (nonextractable)...

This winter was hardly a winter by usual standards. At Grand Forks six record highs were set in February, a month which averaged 11°F above normal, and a -20° reading was not recorded the entire season for the first time in 50 years. Fort Peck Lake in Montana finally iced...

Laboratory-produced progeny of Coregonus alpenae, C. zenithicus, C. hoyi, and C. kiyi and their wild parents were used to examine the contributions of genotype and environment to morphology. Morphological differences between parents and offspring were generally greater than those between species, indicating strong environmental effects. The phenotypic effects on most characters can probably be attributed to different developmental...

Starch gel electrophoresis was used as a means of recognizing species and stocks in Lake Superior Coregonus. Allelic variability at isocitrate dehydrogenase and glycerol-3-phosphate dehydrogenase loci was recorded for samples of lake herring (Coregonus artedii), bloater (C. hoyi), kiyi (C. kiyi), and shortjaw cisco (C. zenithicus) from five Lake Superior...

No unique phenotypes were observed among the specimens and no single species clearly dominated the samples. I conclude therefore that the species Coregonus prognathus has no taxonomic validity. Because of the poor condition and uncertain identity of the holotype, Coregonus prognathus should be considered a nomen dubium....

Researchers predicted that several hundred years would be required before DDT (1,1,1 trichloro-2,2-bis [P-chlorophyl] ethane) and its metabolites were likely to decrease to nondetectable levels in Lake Michigan. But following the ban on DDT in 1970, residues of total DDT in Lake Michigan lake trout (Salvelinus namaycush) declined rapidly from...

No abstract available....

Using glass capillary gas chromatography (GC) and ion-pair reversed-phase high-performance liquid chromatography (HPLC), a pair of structurally similar microbicides, benzyl diisobutylphenoxyethoxyethyl dimethyl ammonium chloride and its cresoxy-analogue, were effectively resolved and accurately quantified with a high degree of selectivity and specificity. Optimization of conditions in the chromatographic systems to attain...

No abstract available....

U.S. Geological Survey...

Fecal extracts and blood sera from 113 ducks showing clinical signs of botulism were examined for Clostridium botulinum type C toxin by means of the mouse toxicity test to evaluate coproexamination as a diagnostic procedure, as compared with demonstration of toxin in serum. When death of test mice unprotected with type...

Review of: Handbook of drugs and chemicals used in the treatment and control of fish diseases. N. Herwig; 1979; Charles C. Thomas, Co., Springfield, Illinois....

The Golden Eagle (Aquila chrysaetos) is the largest predatory bird in North America and is well known for its predatory abilities. Attacks have been reported on mammals such as whitetail jackrabbits (Lepus townsendi) (McGahan 1967, J. Wildl. Mgmt. 31: 496), pronghorn antelope (Antilocapra americana) (Bruhns 1970, Can. Field-Natur. 84: 301),...

Castor bean (Ricinus communis) poisoning accounted for the death of several thousand ducks in the Texas panhandle in the fall and winter months of 1969-1971.Signs of intoxication resembled those of botulism, except for mucoid, blood-tinged excreta. The most common lesions were severe fatty change in the liver, widely distributed internal...

In 1979, pink salmon (Oncorhynchus gorbuscha) completed expansion of their range from Lake Superior into each of the other four Great Lakes. Record numbers of pink salmon were observed during the 1979 spawning migrations into Lake Superior tributaries. Although the species was introduced into Lake Superior 24 years ago, movement into the...