The effect of changes in temperature and food on the development of Calanus finmarchicus and Calanus helgolandicus populations

Abstract

We studied the response in development times of Calanus finmarchicus and Calanus helgolandicus to changes in temperature and food conditions. Grazing experiments were performed at different temperatures for both species, and the results were implemented in a stage-resolved zooplankton population model that predicted development times from biomass increments controlled by ingestion and metabolic losses. Predictions were validated against development data from the literature, and show that C. finmarchicus develops faster than C. helgolandicus below 11uC and slower above. The different relative development rates of the species are related to different temperature responses in ingestion rates. A temperature increase of 1uC to 2uC may have consequences for the relative contribution of C. helgolandicus and C. finmarchicus to the copepod community, and both seasonal and spatial displacements of the Calanus populations can be expected under climate change.

Copepod Life Strategy and Population Viability in Response to Prey Timing and Temperature: Testing a New Model across Latitude, Time, and the Size Spectrum

“…to be suppressed at low temperatures, i.e., to show a very high Q 10 compared with the community-level value (Campbell et al, 2001;Møller et al, 2012).…”

“…It is not always fair, however, to associate a particular u 0 value with a particular species over the full range of temperatures included. As discuss further, the temperature response of an individual species is often dome-shaped, a window of habitat tolerance (Møller et al, 2012;Alcaraz et al, 2014), whereas Coltrane 1.0 uses the monotonic, power-law response observable at the community level (Forster et al, 2011). C. finmarchicus, for example, is fit well by u 0 = 0.007 d −1 at higher temperatures (4-12 • C), whereas near 0 • C in Disko Bay, it has been observed to be considerably smaller than extrapolation along the u 0 = 0.007 d −1 power law would predict.…”

Distinct Communities of Free-Living and Copepod-Associated Microorganisms along a Salinity Gradient in Godthåbsfjord, West Greenland

“…Based on our results, changes in salinity and stratification due to meltwater 8 / ARCTIC, ANTARCTIC, AND ALPINE RESEARCH runoff would strongly influence the free-living microbial community composition, especially Bacteria, Archaea, and Alphaproteobacteria. In Godthåbsfjord, changes in water temperature and meltwater intrusions are also expected to alter the zooplankton community compositions (Tang et al, 2011b;Møller et al, 2012), which could lead to the emergence of different zooplankton-associated bacterial communities. We suggest that climate change research in Greenland and other Arctic regions take into consideration the potential changes and responses of these microbial islands.…”

Reduced up-regulation of gene expression in response to elevated temperatures in the mid-Atlantic population of Calanus finmarchicus

“…The study showed that this population had a strong transcriptomic response to an increase in temperature (from 0°C to 15°C) involving up-regulation of genes related to protein folding, transcription, translation and metabolism, and suggested 5°C as an optimum temperature. Physiological experiments on C. finmarchicus from the same area support this suggestion (Hjorth and Nielsen, 2011;Kjellerup et al, 2012), while studies from warmer areas suggest 10-12°C as an optimal temperature for C. finmarchicus (Harris et al, 2000;Møller et al, 2012). Given these observations and the fact that the distribution of C. finmarchicus is characterised by geographically varying ranges of temperature, salinity and light conditions (Melle et al, 2014), it is likely that response to environmental factors in C. finmarchicus is population-specific.…”