57 research outputs found
Above and below the water: Social/ecological transformation in northwest Newfoundland
Marine fisheries and fishing societies develop around the resources provided by a particular ecosystem. As they exploit these resources, fisheries transform the ecosystem, which pushes fishery and society to adapt in turn. This process is illustrated by fisheries, ecological and social data tracking dramatic changes on Newfoundland\u27s Northern Peninsula and its adjacent marine ecosystem, the northern Gulf of St. Lawrence. There a longstanding fishery for cod and other groundfish collapsed in the 1990s, and was replaced by fisheries targeting invertebrates. The new invertebrate fisheries have different socioeconomic characteristics than the former groundfish fisheries. The shift in target species reflects deep ecological changes that were underway at least a decade before official recognition of the crisis. Our analysis of biological data reveals that the main ecological changes occurred during “the glory years” of the 1980s, when Newfoundland\u27s domestic fisheries were at their peak. Overfishing and interactions with adverse climatic conditions drove the changes. As the ecosystem transformed, human population declined due to outmigration, and social indicators show signs of distress. Accounts by outport residents paint a generational picture of social change
A key to the stromateoid fishes
Originally issued as Reference No. 69-70, series later renamed WHOI-.Our primary purpose in preparing "A Key to the Stromateoid
Fishes" is to provide field workers and curators with a convenient
and concise aid for the identification of the diverse species in this
somewhat difficult group . Secondarily, we hope to present , through
the keys , a summary of the present state of our knowledge of these
fi.shes, and to indicate areas where further investigation is needed .Supported by the National Science Foundation under Grants GB-7108 and GZ-259
First record of the European Giant File Clam, Acesta excavata (Bivalvia: Pectinoidea: Limidae), in the Northwest Atlantic
Two large bivalve specimens collected in Bay d’Espoir, a deep fjord situated on the south coast of Newfoundland, are described and identified as belonging to the species Acesta excavata (Fabricius 1779). In situ observations onboard the manned submersible PISCES IV and color videos have provided information on the vertical distribution, density and habitat of the species. Maximum abundances of about 15 large individuals/m2 occurred on sheltered rock outcrops at depth ranging from 550 to 775 m, where warm (6°C) continental slope water is found. Differences in shape and thickness between the valves of the two specimens appear to be related to the degree of exposure to rock falls (i.e., sheltered versus exposed habitat). Prior to this account, the European Giant File Clam had never been encountered west of the Azores Islands in the North Atlantic
Benthic fauna of the Gulf of Maine sampled by R/V Gosnold Cruise 179 and DSRV Alvin Dives 329, 330, 331, and 404 : infaunal species list
Bottom samples were collected in the Gulf of Maine during July,
1971 and June, 1972 using DSRV ALVIN and RV GOSNOLD. The techniques and
results are embodied in a paper entitled "Quantitative Biological
Assessment of the Benthic Fauna in the Deep Basins of the Gulf of Maine"
by G. T. Rowe, P. T. Polloni and R. L. Haedrich. Many of the conclusions
made in that paper were based on summaries of the abundance of each
benthic species of living invertebrate animal in each kind of sample,
but those original data would not be accepted by the journal (JOURNAL OF
THE FISHERIES RESEARCH BOARD OF CANADA) because the table was too long.
The purpose of this technical report is to put those raw data in a form
available(on request from the authors)to any interested ecologists.The work was supported by ONR Contract N00014 - 66 - C00284 and
NSF Grant GA 31235X
Zonation and faunal composition of epibenthic populations on the continental slope south of New England
The epibenthic macrofauna, including demersal fishes, between 140 and 1900 m on the continental slope south of New England was found to be distributed in three zones: shallow (141-285 m), middle (393-1095 m), and deep (1270-1928 m). Fauna! boundaries were associated with the transition zones from shelf to upper continental slope and from upper to lower continental slope. The small Alvin Canyon was not faunally distinct. Fishes and echinoderms were the most abundant taxa, the former predominant in shallow and middle depths and the latter predominating deeper...
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...
Life history tactics of Atlantic salmon in Newfoundland
Popular articles about the Atlantic salmon (Salmo salar) usually state that ‘the Atlantic salmon is an anadromous species’, e.g. publications by the Atlantic Salmon Federation (North America), Atlantic Salmon Trust (UK), and WWF (World Wildlife Fund), and the life history is depicted as migration of juveniles from fresh water to the marine environment, with a return to where the fish were born as spawning adults. These publications and illustrations are well done and very informative, and sufficient for the messages the organisations wish to communicate. Nevertheless, as well as performing marvelous migrations, Atlantic salmon also show a wonderful range of life history tactics, and may be considered as a polytypic species
A key to the stromateoid fishes
This second edition of "A Key to the Stromateoid Fishes" is a partially
up-dated version of the original (W.H.O.I. Ref. No. 69-70, September 1969).Our primary purpose in preparing "A Key to the Stromateoid
Fishes" is to provide field workers and curators with a convenient
and concise aid for the identification of the diverse species in this
somewhat difficult group.
Secondarily, we hope to present, through
the keys, a summary of the present state of our knowledge of these
fishes, and to indicate areas where further investigation is needed.
The keys which compose this handbook have been derived from
several sources. Some are slightly modified from already published
or about-to-be-published sources.
Others form a part of manuscripts
in preparation. A third group of keys has
been constructed from published
species descriptions and our own often meagre data.
The keys are intended primarily for larger specimens.
Small stromateoids are particularly confusing, and it is not our purpose
to treat them here. The well-known and marked allometric growth in
stromateoids remains a problem, and those who use these keys should
be aware that the body proportions
of very large and/or very small
specimens can fall well outside the limits here set.
We expect and
hope for corrections and improvements to the keys, and have left
them double-spaced so comments
may be written in by users.
We have
not attempted to settle nomenclatural problems, but have used the oldest
name we know of when a choice is necessary.
Neither have we
gone into the problem of synonymy to any great extent.
In some cases
we have approached this problem by including two names under one
couplet in a key. The choice of which name to employ is thus passed
on to the user.Prepared for the National Science Foundation
under Grants GA-31365X, GB-710B, and GZ-259
Ceratoscopelus maderensis : pecular sound-scattering layer identified with this myctophid fish
Reprint. Science, vol. 160, no. 3831, 1968, pp. 991-993. Originally issued as Reference No. 68-58, series later renamed WHOI-.A sound- scattering layer, composed of discrete
hyperbolic echo-sequences and apparently restricted to the
Slope Water region of the western North Atlantic, has been
identified from the Deep Submergence Research Vehicle ALVIN
with schools of the myctophid fish Ceratoscopelus maderensis.
By diving into the layer and using ALVIN's echo-ranging sonar,
we approached and visually identified the sound scatterers. The
number of echo sequences observed with the surface echo-sounder
(1 /23. 76 x 105 cubic meters of water) checked roughly with the
number of sonar targets observed from the submarine (1/7. 45 x
105 cubic meters) . The fish schools appeared to be 5 to 10 meters
thick, 10 to 100 meters in diameter, and on centers 100 to 200
meters apart. Density within schools was estimated at 10 to 15
fish per cubic meter.Supported in part by contracts Nonr-3484(00)
and Nonr-4029(00) and by NSF grant GB-4431
Long-Term Observations of Epibenthic Fish Zonation in the Deep Northern Gulf of Mexico
A total of 172 bottom trawl/skimmer samples (183 to 3655-m depth) from three deep-sea studies, R/V Alaminos cruises (1964-1973), Northern Gulf of Mexico Continental Slope (NGoMCS) study (1983-1985) and Deep Gulf of Mexico Benthos (DGoMB) program (2000 to 2002), were compiled to examine temporal and large-scale changes in epibenthic fish species composition. Based on percent species shared among samples, faunal groups (≥10% species shared) consistently reoccurred over time on the shelf-break (ca. 200 m), upper-slope (ca. 300 to 500 m) and upper-to-mid slope (ca. 500 to 1500 m) depths. These similar depth groups also merged when the three studies were pooled together, suggesting that there has been no large-scale temporal change in depth zonation on the upper section of the continental margin. Permutational multivariate analysis of variance (PERMANOVA) also detected no significant species changes on the limited sites and areas that have been revisited across the studies (P>0.05). Based on the ordination of the species shared among samples, species replacement was a continuum along a depth or macrobenthos biomass gradient. Despite the well-known, close, negative relationship between water depth and macrofaunal biomass, the fish species changed more rapidly at depth shallower than 1,000 m, but the rate of change was surprisingly slow at the highest macrofaunal biomass (>100 mg C m(-2)), suggesting that the composition of epibenthic fishes was not altered in response to the extremely high macrofaunal biomass in the upper Mississippi and De Soto Submarine Canyons. An alternative is that the pattern of fish species turnover is related to the decline in macrofaunal biomass, the presumptive prey of the fish, along the depth gradient
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