Habitat Occupancy by Bachman's Sparrow in the Francis Marion National Forest before and after Hurricane Hugo

The Auk ◽  
1991 ◽  
Vol 108 (3) ◽  
pp. 723-725 ◽  
Author(s):  
John B. Dunning, ◽  
Bryan D. Watts
Author(s):  
Kimberly Szcondronski ◽  
Diane Debinski

The pristine, protected ecosystem of Grand Teton National Park (GRTE) is the ideal location to study the relationships between butterfly populations and the habitats on which these insects depend. Two montane meadow butterfly species, Parnassius clodius and Parnassius smintheus, were investigated in this study to identify patterns of habitat occupancy relating to variables across GRTE and into the surrounding territory of Bridger–Teton National Forest (BTNF). Population dynamics of P. clodius have been intensively studied by our research group over several consecutive years in one isolated population in Grand Teton National Park. However, little has been investigated regarding the Parnassian butterflies’ population range across the GRTE ecosystem. For this study, presence-absence butterfly surveys were conducted across 45 meadow sites in preferred habitat during the Parnassius flight season (June – July 2013). We found that P. clodius occupied 80% of the meadows surveyed, which was far greater than was originally predicted. P. smintheus, the more rare Parnassian butterfly in the GRTE ecosystem, was only found at 9% of the meadows surveyed. Understanding population ranges and habitat limits of these butterfly populations will be useful for managers and scientists within GRTE, and will assist conservation efforts for other related Parnassian species that are threatened or endangered worldwide due to habitat loss and climate change.


2003 ◽  
Vol 33 (12) ◽  
pp. 2436-2442 ◽  
Author(s):  
Annie E Tibbels ◽  
Allen Kurta

We investigated the use of red pine (Pinus resinosa Ait.) plantations by bats in the Manistee National Forest of Michigan. Using ultrasonic detectors, we compared the activity of bats in the interior of stands of red pine and in openings within the stands, both before and after thinning (mean time after thinning = 7 years). Bat activity was more than 20 times greater in small openings within thinned and unthinned stands than within the stands themselves, and bat activity was associated with greater insect abundance in openings. Thinning lead to a significant change in structural complexity, as shown by a 39% decrease in basal area and a 45% decline in tree density, although these changes did not lead to an increase in use of red pine stands by bats. Red pine plantations, even after thinning, most likely are too structurally complex and have low insect abundance, making them a largely unsuitable habitat for bats.


Author(s):  
J. Temple Black

Tool materials used in ultramicrotomy are glass, developed by Latta and Hartmann (1) and diamond, introduced by Fernandez-Moran (2). While diamonds produce more good sections per knife edge than glass, they are expensive; require careful mounting and handling; and are time consuming to clean before and after usage, purchase from vendors (3-6 months waiting time), and regrind. Glass offers an easily accessible, inexpensive material ($0.04 per knife) with very high compressive strength (3) that can be employed in microtomy of metals (4) as well as biological materials. When the orthogonal machining process is being studied, glass offers additional advantages. Sections of metal or plastic can be dried down on the rake face, coated with Au-Pd, and examined directly in the SEM with no additional handling (5). Figure 1 shows aluminum chips microtomed with a 75° glass knife at a cutting speed of 1 mm/sec with a depth of cut of 1000 Å lying on the rake face of the knife.


Author(s):  
R. F. Bils ◽  
W. F. Diller ◽  
F. Huth

Phosgene still plays an important role as a toxic substance in the chemical industry. Thiess (1968) recently reported observations on numerous cases of phosgene poisoning. A serious difficulty in the clinical handling of phosgene poisoning cases is a relatively long latent period, up to 12 hours, with no obvious signs of severity. At about 12 hours heavy lung edema appears suddenly, however changes can be seen in routine X-rays taken after only a few hours' exposure (Diller et al., 1969). This study was undertaken to correlate these early changes seen by the roengenologist with morphological alterations in the lungs seen in the'light and electron microscopes.Forty-two adult male and female Beagle dogs were selected for these exposure experiments. Treated animals were exposed to 94.5-107-5 ppm phosgene for 10 min. in a 15 m3 chamber. Roentgenograms were made of the thorax of each animal before and after exposure, up to 24 hrs.


Author(s):  
M. H. Wheeler ◽  
W. J. Tolmsoff ◽  
A. A. Bell

(+)-Scytalone [3,4-dihydro-3,6,8-trihydroxy-l-(2Hj-naphthalenone] and 1,8-di- hydroxynaphthalene (DHN) have been proposed as intermediates of melanin synthesis in the fungi Verticillium dahliae (1, 2, 3, 4) and Thielaviopsis basicola (4, 5). Scytalone is enzymatically dehydrated by V. dahliae to 1,3,8-trihydroxynaphthalene which is then reduced to (-)-vermelone [(-)-3,4- dihydro-3,8-dihydroxy-1(2H)-naphthalenone]. Vermelone is subsequently dehydrated to DHN which is enzymatically polymerized to melanin.Melanin formation in Curvularia sp., Alternaria sp., and Drechslera soro- kiniana was examined by light and electron-transmission microscopy. Wild-type isolates of each fungus were compared with albino mutants before and after treatment with 1 mM scytalone or 0.1 mM DHN in 50 mM potassium phosphate buffer, pH 7.0. Both chemicals were converted to dark pigments in the walls of hyphae and conidia of the albino mutants. The darkened cells were similar in appearance to corresponding cells of the wild types under the light microscope.


Author(s):  
T. Gulik-Krzywicki ◽  
M.J. Costello

Freeze-etching electron microscopy is currently one of the best methods for studying molecular organization of biological materials. Its application, however, is still limited by our imprecise knowledge about the perturbations of the original organization which may occur during quenching and fracturing of the samples and during the replication of fractured surfaces. Although it is well known that the preservation of the molecular organization of biological materials is critically dependent on the rate of freezing of the samples, little information is presently available concerning the nature and the extent of freezing-rate dependent perturbations of the original organizations. In order to obtain this information, we have developed a method based on the comparison of x-ray diffraction patterns of samples before and after freezing, prior to fracturing and replication.Our experimental set-up is shown in Fig. 1. The sample to be quenched is placed on its holder which is then mounted on a small metal holder (O) fixed on a glass capillary (p), whose position is controlled by a micromanipulator.


Author(s):  
R. M. Anderson

Aluminum-copper-silicon thin films have been considered as an interconnection metallurgy for integrated circuit applications. Various schemes have been proposed to incorporate small percent-ages of silicon into films that typically contain two to five percent copper. We undertook a study of the total effect of silicon on the aluminum copper film as revealed by transmission electron microscopy, scanning electron microscopy, x-ray diffraction and ion microprobe techniques as a function of the various deposition methods.X-ray investigations noted a change in solid solution concentration as a function of Si content before and after heat-treatment. The amount of solid solution in the Al increased with heat-treatment for films with ≥2% silicon and decreased for films <2% silicon.


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