scholarly journals Abundance and distribution of Calanus finmarchicus on the Georges Bank during 1995 and 1996

2000 ◽  
Vol 57 (6) ◽  
pp. 1664-1685 ◽  
Author(s):  
E Durbin
Keyword(s):  
Calanus Finmarchicus ◽  
Georges Bank ◽  
Abundance And Distribution

scholarly journals Zooplankton abundance trends on Georges Bank, 1977–2004

2007 ◽  
Vol 64 (5) ◽  
pp. 909-919 ◽  
Author(s):  
Joseph Kane
Keyword(s):  
Calanus Finmarchicus ◽  
Zooplankton Abundance ◽  
Georges Bank ◽  
Total Zooplankton ◽  
Key Factors ◽  
The Past ◽  
Abundance Trends ◽  
Temora Longicornis ◽  
Northeast Us ◽  
Centropages Typicus

Abstract Kane, J. 2007. Zooplankton abundance trends on Georges Bank, 1977–2004. – ICES Journal of Marine Science, 64: 909–919. Interannual trends in Georges Bank zooplankton abundance are described and related to variations in environmental variables for the period 1977–2004. Total zooplankton counts increased to above average levels in 1989 and stayed over or close to average through 2004. This analysis identified a group of taxa including Centropages typicus, Metridia lucens, and Temora longicornis that had similar interannual patterns of abundance. All these taxa increased sharply in the early 1990s and remained high through 2001. Some taxa declined sharply in 2002, others have continued elevated through 2004. Total zooplankton counts in the past two years were also boosted by a substantial increase in the abundance of the copepod Calanus finmarchicus. Evidence is presented that these changes may be related to variations in Scotian Shelf inflow, which freshened water on the Northeast US continental shelf, perhaps increasing both primary production and the influx of zooplankton into the region. There was a positive correlation between the biomass of pelagic predators and the abundance of several zooplankton taxa, suggesting that bottom-up processes and advective supply are the key factors that regulate the Georges Bank foodweb.

scholarly journals A comparative study of Calanus finmarchicus mortality patterns at five localities in the North Atlantic

2004 ◽  
Vol 61 (4) ◽  
pp. 687-697 ◽  
Author(s):  
M.D Ohman ◽  
K Eiane ◽  
E.G Durbin ◽  
J.A Runge ◽  
H.-J Hirche
Keyword(s):  
North Atlantic ◽  
Calanus Finmarchicus ◽  
Estimation Methods ◽  
Late Winter ◽  
Zooplankton Abundance ◽  
Biological Interactions ◽  
Georges Bank ◽  
Density Dependent ◽  
The North ◽  
The North Atlantic

Abstract We compare the patterns of stage-specific mortality of Calanus finmarchicus at five localities across the North Atlantic Ocean during the spring–summer period of active population growth: Georges Bank, a continental shelf locality in the NW Atlantic, based on 30 broadscale survey cruises in the US GLOBEC program; the northern North Sea, studied during the historic FLEX program with sampling four times daily for 73 days; Ocean Station M in the central Norwegian Sea, based on an 80-day daily time-series; and Lurefjorden (sampled weekly in late winter–early summer) and Sørfjorden (sampled monthly), two fjords in southwestern Norway characterized by markedly different guilds of predators. The mortality estimation methods included Wood's Population Surface Method, the Vertical Life Table (VLT) method, and a modified VLT, according to the study site and copepod recruitment schedules. Contrary to assumptions implicit in many simulation models and indirect methods for estimating zooplankton mortality, both rates and stage-specific patterns of mortality of C. finmarchicus vary appreciably across the North Atlantic. Characteristics of local environments, including the predator field in particular, appear to strongly influence mortality schedules in different regions. In at least two sites (Georges Bank and Ocean Station M), mortality rates of early stages of C. finmarchicus are density-dependent. We attribute this density-dependent mortality to egg cannibalism, which introduces non-linear population responses to changing environmental conditions. Region-specific biological interactions can substantially modify the effects of physical climate variability and render simple linear relationships between climate and zooplankton abundance unlikely.

Coupling of an individual‐based population dynamic model of Calanus finmarchicus to a circulation model for the Georges Bank region

1998 ◽  
Vol 7 (3‐4) ◽  
pp. 219-234 ◽  
Author(s):  
CHARLES B. MILLER ◽  
DANIEL R. LYNCH ◽  
FRANÇOIS CARLOTTI ◽  
WENDY GENTLEMAN ◽  
CRAIG V. W. LEWIS
Keyword(s):  
Dynamic Model ◽  
Population Dynamic ◽  
Circulation Model ◽  
Calanus Finmarchicus ◽  
Georges Bank ◽  
Population Dynamic Model

scholarly journals End of the century CO2 concentrations do not have a negative effect on vital rates of Calanus finmarchicus, an ecologically critical planktonic species in North Atlantic ecosystems

2016 ◽  
Vol 73 (3) ◽  
pp. 937-950 ◽  
Author(s):  
Jeffrey A. Runge ◽  
David M. Fields ◽  
Cameron R. S. Thompson ◽  
Steven D. Shema ◽  
Reidun M. Bjelland ◽  
...  
Keyword(s):  
North Atlantic ◽  
North Atlantic Ocean ◽  
Co2 Concentration ◽  
Calanus Finmarchicus ◽  
Vital Rates ◽  
Significant Treatment ◽  
The North ◽  
Pco2 Treatment ◽  
Negative Effect ◽  
Abundance And Distribution

Abstract The Subarctic copepod, Calanus finmarchicus, is an ecologically critical foundation species throughout the North Atlantic Ocean. Any change in the abundance and distribution of C. finmarchicus would have profound effects on North Atlantic pelagic ecosystems and the services that they support, particularly on the coastal shelves located at the southern margins of the species' range. We tested the hypothesis that the physiological rates and processes of C. finmarchicus, determining its vital rates, are unaffected by increases in CO2 concentration predicted to occur in the surface waters of the ocean during the next 100 years. We reared C. finmarchicus from eggs to adults at a control (580 µatm, the ambient concentration at the laboratory's seawater intake) and at predicted mid-range (1200 µatm) and high (1900 µatm) pCO2. There was no significant effect of pCO2 on development times, lipid accumulation, feeding rate, or metabolic rate. Small but significant treatment effects were found in body length and mass (in terms of dry, carbon and nitrogen mass), notably a somewhat larger body size at the mid-pCO2 treatment; that is, a putatively beneficial effect. Based on these results, and a review of other studies of Calanus, we conclude that the present parameterizations of vital rates in models of C. finmarchicus population dynamics, used to generate scenarios of abundance and distribution of this species under future conditions, do not require an “ocean acidification effect” adjustment. A review of research on planktonic copepods indicates that, with only a few exceptions, impacts of increased CO2 are small at the levels predicted to occur during the next century.

scholarly journals Late fall-early winter recruitment of Calanus finmarchicus on Georges Bank

1997 ◽  
Vol 151 ◽  
pp. 103-114 ◽  
Author(s):  
EG Durbin ◽  
JA Runge ◽  
RG Campbell ◽  
PR Garrahan ◽  
MC Casas ◽  
...  
Keyword(s):  
Calanus Finmarchicus ◽  
Georges Bank ◽  
Early Winter ◽  
Late Fall
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