Abstract
The ubiquitous oceanic copepod Calanus finmarchicus is the major link between primary producers and important fish stocks in the North Atlantic Ocean and adjacent seas. Despite over a century of research on growth and development of this key species, the effect of predation risk on these processes remains elusive. We tested how food level and chemical cues from a fish predator influence growth and development of C. finmarchicus, using a predator naïve laboratory population. Copepods reached adult stage earlier both in response to high food and to predator cues in our experiment. High food also increased growth and lipid accumulation. In contrast, perceived predation risk triggered reduced size and lipid fullness, indicating a decoupling of growth and development rates. Our results demonstrate that chemical predator cues can influence life history strategies in C. finmarchicus, and suggest that present and future patterns in oceanic zooplankton size and population dynamics may also reflect differences in predation risk.
Ecology. First published: 01 October 2020
DOI: 10.1002/ecy.3214
Publication webpage.
Kristina Øie Kvile*,§, Dag Altin#, Lotte Thommesen*, and Josefin Titelman*
* Department of Biosciences, University of Oslo, PO Box 1066 Blindern, 0316 Oslo, Norway
§ Norwegian Institute for Water Research, Gaustadalléen 21, 0349 Oslo, Norway
# BioTrix, NO‐7022 Trondheim, Norway / Department of Biology, Norwegian University of Science and Technology, NO‐7491 Trondheim, Norway