3,787 research outputs found
Effects of the June 1995 Freshet on The Main Virginia Tributaries to the Chesapeake Bay
Environmental conditions in the Virginian waters of the Chesapeake Bay area during the summerof 1995 have been characterized as a severe drought. This drought was punctuated on 27 June with a headwater (James and Rappahannock River) rain storm that produced a freshet . Although it did not rain in the Tidewater area of Virginia, surface salinities were depressed by the run-off, and main-stem bottom ox}\u27gen levels dropped to z.ero in the James and Rappahannock rivers. The effects of the reduced oxygen were apparent on the James River oyster stock, particularly the reduction in spatfall, and to a lesser degree on the Rappahannock River young-of-the-year striped bass index. Long-term effects of the June flood and/or the drought must be monitored
Chesapeake Bay Status of Stocks Report 1988-89 : Virginia Juvenile Finfish Trawl Data
The results presented here are the tabular Catch-per-Unit-gffort (CPUE) Virginia trawl data for young of the year and yearling finfish from the inception date of the survey (1954) to the present.
These data will also be the basis for developing a Virginia juvenile finfish index in 1989-1990
Two- and three-dimensional simulations of core-collapse supernovae with CHIMERA
Ascertaining the core-collapse supernova mechanism is a complex, and yet
unsolved, problem dependent on the interaction of general relativity,
hydrodynamics, neutrino transport, neutrino-matter interactions, and nuclear
equations of state and reaction kinetics. Ab initio modeling of core-collapse
supernovae and their nucleosynthetic outcomes requires care in the coupling and
approximations of the physical components. We have built our multi-physics
CHIMERA code for supernova modeling in 1-, 2-, and 3-D, using ray-by-ray
neutrino transport, approximate general relativity, and detailed neutrino and
nuclear physics. We discuss some early results from our current series of
exploding 2D simulations and our work to perform computationally tractable
simulations in 3D using the "Yin-Yang" grid.Comment: Proceedings of the 12th Symposium on Nuclei in the Cosmos. 5-12
August 2012. Cairns, Australia. Published online at
http://pos.sissa.it/archive/conferences/146/208/NIC%20XII_208.pdf Corrected
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Biogeographic anomaly or human introduction: A cryptogenic population of tree skink (Reptilia: Squamata) from the Cook Islands, Oceania
Archaeological and molecular data have revealed that the present day faunas of many island groups in Melanesia, Polynesia, and Micronesia are not representative of the biodiversity generated within this region on an evolutionary timescale. Erroneous inferences regarding the mechanisms of speciation and the significance of long distance dispersal in shaping the present diversity of these island systems have resulted from this incomplete diversity and distributional data. The lizard fauna east of Samoa has been suggested to derive entirely from human-mediated introductions, a distribution congruent with biogeographic patterns for other Pacific species. Distinguishing between introduced populations and those that result from natural colonization events is difficult, although molecular data provide a useful means for elucidating population history and identifying the likely sources of introductions. We use molecular data (1726 bp of mitochondrial DNA and 286 bp of nuclear DNA) to evaluate a population of arboreal lizards from the Cook Islands and to determine whether this arboreal skink population is the sole endemic component of the lizard fauna east of Samoa or the result of human-mediated introduction. © 2010 The Linnean Society of London
Juvenile Fish and Blue Crab Stock Assessment Program Bottom Trawl Survey Annual Data Summary Report Volume 1996
Juvenile Finfish and Blue Crab Stock Assessment Program Bottom Trawl Survey Annual Data Summary Report Series Volume 1993
The Virginia Institute of Marine Science (VIMS) has conducted a trawl survey dating back to 1955. Over these forty years methods and objectives have varied according to funding sources and state and/or federal mandates. The present thrust of the program is to provide juvenile indices of relative abundance for recreationally, commercially, and ecologically important finfish and invertebrates. These measures of juvenile abundance are widely used as a key element in the management of the Atlantic States\u27 coastal fishery resources. Estimates of juveniles (age-0) have been found to provide a reliable and early indicator of future year class strength. A review of previously available indices of juvenile abundance for important fishery resource species of the Chesapeake Bay by the Chesapeake Bay Stock Assessment Committee (CBSAC), a federal/state committee sponsored and funded by the National Oceanic and Atmospheric Administration (NOAA), resulted in the recommendation that, a unified, consistent trawl program should be one of the primary monitoring tools for finfish and crab stock assessment. (Chesapeake Bay Program Stock Assessment Plan, Chesapeake Executive Council 1988). There were several notable results in the survey this year. Two groups of invertebrates were officially added to the collection list. The penaeid shrimp are only of minor significance in Chesapeake Bay, but in certain years (1991) their abundance has been high enough to rank in the top twenty species caught. The squid species of the family Lologinidae have been include due to their overall abundance in the main stem bay (ranked 11th overall), Atlantic coast commercial value, and ecological factors. Both these groups of species were collected in past years but on an inconsistent basis. Other results worth mentioning include a large increase in the scup abundance, over six times that of the previous year. Although older summer flounder appeared abundant, there was a substantial decrease in juvenile abundance near the historic low of 1988. The blue crab population continues to be depressed, although catch rates were slightly higher than in recent years. In the tributaries, there has been a marked increase in young-of-the-year (YOY) striped bass and white perch which began in November and continued into the early months of 1994. Atmospherically, 1993 included a mild winter followed by an unusually cool, wet spring. The summer was one of drought conditions and record highs, making it the second hottest summer in recorded history. The purpose of this summary is to provide an accurate account of trawl survey sampling performed during the calendar year 1993. Previous volumes of this series have served as excellent reference guides to resource managers, scientists, academics, as well as the general public. Since there are other venues which presently detail specific results of these data (Geer et al, 1993), conclusions are kept at a minimum in order to provide the most information in the available space
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