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

By M. Ohman, K. Eiane, E. Durbin, J. Runge, H. Hirche. 2004

92 citations recorded by the source corpus.

Author(s): Ohman, MD; Eiane, K; Durbin, EG; Runge, JA; Hirche, HJ | 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 Sorfjorden (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. © 2004 International Council for the Exploration of the Sea. Published by Elsevier Ltd. All rights reserved.

Subfields: Global and Planetary Change, Oceanography

View Paper: https://www.semanticscholar.org/paper/eff893ad6959764fe69823809161f69605dafe42

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Global and Planetary Change

1. K. Eiane
2. M. Ohman
3. J. Runge
4. Malin Daase
5. Gyda Arnkværn
6. P. Pepin
7. W. Gurney
8. Simon N. Wood

In Oceanography

1. K. Eiane
2. Malin Daase
3. M. Ohman
4. J. Runge
5. Gyda Arnkværn
6. M. Heath
7. B. Niehoff
8. P. Pepin

Citations in the corpus

• Biogeochemical fluxes through mesozooplankton (2006, unknown): “Out of five tested sites, two showed evidence of carnivory of adults on eggs ( Ohman et al. , 2004).”
• Stage-specific mortality of Calanus finmarchicus, Pseudocalanus elongatus and Oithona similis on Fladen Ground, North Sea, during a spring bloom (2004, result): “The stage-specific decline in mortality rate is similar to that observed for Calanus spp. in Lurefjorden, a fjord dominated by invertebrate predators (Eiane et al. 2002), as well as in the open Norwegian Sea at Ocean Station M (Ohman et al. 2004).”
• The North Atlantic Ocean as habitat for Calanus finmarchicus: Environmental factors and life history traits (2014, background): “…of C. finmarchicus is mainly governed by temperature, food availability and/or con-specific abundance, which results in marked seasonal and regional differences in stage-specific mortality patterns (Ohman and Hirche, 2001; Ohman et al., 2002, 2004; Heath et al., 2008; Plourde et al., 2009b).”
• Dynamics of coexisting Calanus finmarchicus, Calanus glacialis and Calanus hyperboreus populations in a high-Arctic fjord (2005, result): “Our mortality estimates resemble the estimates reported from a fjord in southwestern Norway where predation from planktivorous fish has the most pronounced effect on survival (Eiane et al. 2002), and from Georges Bank (Ohman et al. 2004).”
• Ocean-scale modelling of the distribution, abundance, and seasonal dynamics of the copepod Calanus finmarchicus (2006, background): “Field estimates of mortality rates are sparse, but it is clear that they are strongly stage-dependent (Eiane et al. 2002; Ohman et al. 2004).”