Georges Bank

© The Author(s), 1987. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Backus, Richard H. (1987). Georges Bank. Massachusetts Institute of Technology.Georges Bank provides a basic and indispensable reference tool for anyone involved in studying the bank or in making decisions about its use. Until now debates about alternative uses of the bank have been hampered by the fact that much of the basic research has been available only to specialists and has been scattered among many publications. In bringing the available information on this complex region together for the first time, Georges Bank provides a basic and indispensable reference tool for anyone involved in studying the bank or in making decisions about its use. Moreover, the depth and clarity of the book's 57 articles and 8 nontechnical introductions will make it useful for anyone involved in oceanographic or ocean policy studies.Sections cover all aspects of this huge marine ecosystem - geology, weather and climate, physical oceanography, chemistry, phytoplankton, primary production, zoology and secondary production, the fisheries, and conflicting uses. Georges Bank is the first major project of the Coastal Research Center of Woods Hole Oceanographic Institution. The editor-in-chief, Richard H. Backus, is chairman of the Institutions's biology department. Includes 176 six-color maps, 54 four-color illustrations - 392 charts, graphs, and drawings

The vascular flora of Falmouth (Barnstable County) Massachusetts

With a few exceptions, the species on this list of Falmouth vascular plants are substantiated by herbarium sheets, most of which are in the MBLWHOI Library Herbarium (SPWH). We invite improvements to the list by the elimination of errors and by the collection of Falmouth species not yet found. About 880 taxa are listed here, which is about 60% of Barnstable County’s 1440 or so as shown by the County Checklist (Cullina et al. 2011). Barnstable County is a geographically diverse place and not all of its vascular plants are to be expected for any one of its towns, but it seems likely that some dozens of the County’s 560 taxa not yet recorded for Falmouth are to be found in that place. We hope interested field botanists will endeavor to find these “missing” plants, collecting material so that herbarium sheets can be made for deposit in SPWH and their names added to this list. There are also many plants that have not been collected in Falmouth for many years. Material for herbarium sheets is desired for these taxa as well

The concentrating of organisms at fronts: A cold-water fish and a warm-core Gulf Stream ring

Net hauls made in and around a warm-core Gulf Stream ring in April and June 1982 suggest a concentrating of the mesopelagic fish Benthosema glaciale (family Myctophidae) in the frontal zone at the east edge of the ring. In April, Benthosema was found in very small numbers in the two-month old ring, as was to be expected from the subpolar-temperate distribution of this fish and the warm-water origin and age of the ring. By June, age-0 fish had been recruited to the population susceptible to capture by the midwater trawl. These young fish were about five times as abundant at the frontal zone of the ring and about twice as abundant in the ring center as in the adjacent Slope Water. It is proposed that the increased abundance at the ring front results from a concentrating of the original Slope Water population by convergence. The increase of B. glaciale in the center of the ring may be associated with the inwardly spiralling streamers observed in satellite images.A simple advection/diffusion model for both the fish and a passive tracer of the fluid is used to consider a mechanism that might have concentrated the fish at the ring edge. It is assumed that the fish can counter the vertical flow in order to maintain their preferred depth. Swimming in the horizontal is assumed to be random. The result of this behavior is that the fish and the passive tracer are affected differently in flow fields such as those in rings. Solutions to the model equations lead to the conclusion that the abundance of fish at the ring front can be accounted for by convergence. The model and the divergence pattern in the ring, calculated from hydrographic data, show the time necessary to effect the hundred-fold increase in abundance that was observed in the ring front between April and June to be on the order of two weeks to a month. We suggest that the concentrating mechanism described is widely applicable to a variety of frontal phenomena and to a variety of planktonic plants and animals

Mesopelagic fishes in Gulf Stream cold-core rings

Calculations of abundance of midwater fishes in the families Myctophidae, Gonostomatidae, Photichthyidae, and Stemoptychidae for the 1000 m water column were made in cold-core rings and in the nearby Sargasso Sea and Slope Water…

Data report for Atlantic pelagic zoogeography

This data report fulfils two functions. It (1) gives station data for 1022 midwater trawl collections made in the Atlantic Ocean between 1961 and 1974 by the writers and their colleagues (Table 1, Figure 1, and Appendix 1) and for 531 Atlantic neuston collections made between 1964 and 1974 (Table 2 and Appendix 2), and (2) gives the geographic coordinates for a set of boundaries that divides the Atlantic Ocean between the arctic-subarctic boundary and the subtropical convergence at 40°S into a system of faunal regions and provinces (Figure 2 and Appendix 3). The derivation of these boundaries is explained briefly.Prepared for the National Science Foundation under Grant DES 74-23209

Midwater fish data report for warm-core Gulf Stream rings cruises 1981-1982

This data report is for midwater fishes collected during the multidisciplinary Warm-Core Rings Program in 1981 and 1982. Stations were made in and near three warm-core rings on five cruises within a period of 14 months. On Atlantis II cruise 110 (September-October 1981) six stations were made in and around ring 81-D (age two months). Stations were made in the vicinity of ring 82-B on three cruises in 1982--twelve stations during Oceanus 118 (April) when the ring was two months old, 15 stations during Oceanus 121 (June) at age four months, and 19 stations during Oceanus 125 (August) at age 5.5 months. Finally, twelve stations were made in and near meander/ring 82-H (age 0) during Knorr 98 in September/October 1982 (Tables 1-10). The collections were made with a new midwater trawl - the MOCNESS-20 (MOC-20) (Wiebe et al., 1985), a scaled-up version of the MOCNESS-1 (an apparatus for collecting zooplankton; Wiebe et al., 1976) and successor to the MOCNESS-10 (like the MOC-20, a midwater trawl). (The number forming the distinctive part of the name of these nets is equal to the area of the projected mouth in square meters when the apparatus is in a common fishing attitude.) The MOC-20 consists of a set of 3-mm mesh rectangular nets that can be opened and closed by command from the surface via a signal-conducting towing warp. Apparatus attached to the net frame measures and transmits depth, temperature, conductivity, flow, and net-frame angle to the towing ship's laboratory. Flow (net speed), vertical velocity, and net-frame angle allow computation of the water volume filtered . On the WCR cruises a set of five or six nets was used. One net (not used for quantitative analyses) was fished down to 1000 m, then closed and a second net opened. The second and successive nets were closed and opened sequentially at intervals as the apparatus was brought back to the surface. A surface-to-surface cycle with the gear is referred to as a station, the contents of a single net as a collection. In addition to be1ng described by latitude and longitude, stat1ons are located in the same radial coordinate system used to composite the warm-core rings physical data, that is, by distance and bearing from the moving ring center.Funding was provided by the National Scten.ce Foundation under Grant Numbers OCE 80-17270 and OCE 86-20402

The distribution of mesopelagic fishes in the equatorial and western North Atlantic Ocean

Examination of about 290 midwater trawl hauls made to a depth of 1000 m in the equatorial and western North Atlantic Ocean from 1961 to 1968 suggests that at least 10 physical boundaries determine the ranges of mesopelagic fishes. The boundaries delimit six pelagic regions----the Slope Water Region, the Northern Sargasso Sea, the Southern Sargasso Sea, the Gulf of Mexico, the Caribbean Sea, and the Amazonian Region----and partly delimit four others----the Eastern Gyre and the Labrador, Lesser Antillean, and Guinean regions...

Mortality of fish subjected to explosive shock as applied to oil well severance on Georges Bank

A very extensive bibliography of papers on underwater explosions and their effects on marine life has been collected and summarized. When exposed to blast effects, vertebrates with swim bladders or lungs that contain gas are at least an order of magnitude more sensitive than other life. Regression analysis of several different experiments on explosive damage to fish has been combined with reports of fish concentrations and explosives used in oil well severance in order to estimate the probable extent of damage to fish populations from a limited number of severance explosions. Damage per explosion should not be significant and is probably considerably less than that caused by a one hour tow of a bottom trawl net.Prepared for the Technology Assessment and Research Program of the Minerals Management Service, Department of the Interior, under Contract 14-08-0001-18920

Underwater camera positioning by sonar

Originally issued as Reference No. 60-17A pulse sonar system is described for measuring the height above the bottom of an underwater camera and other equipment in the deep oceans. Using this method, cameras have been positioned for photography at depths to about 2,500 fathoms with a precision of about half a fathom. The measurement is achieved by a sonar "pinger" on the equipment, which sends precise 1 pulse-per- second signals to the surface both directly and by reflection from the bottom.Undersea Warfare Branch, Office of Naval Research Under Contract Nonr-1367(00) (NR-261-102