Different Effects of Increased Water Temperature on Egg
Production of Calanus finmarchicus and C. glacialis

A. F. Pasternak^a, E. G. Arashkevich^a, U. Grothe^b, A. B. Nikishina^a, and K. A. Solovyev^a

^a Shirshov Institute of Oceanology, Russian Academy of Sciences, Moscow, Russia

^b University of Troms, Norway
e-mail: pasternakanna@hotmail.com

Received April 16, 2012; in the final form, June 13, 2012

Abstract—Two copepod species, Calanus finmarchicus (a widespread North Atlantic species) and C. glacialis
(an Arctic species), are dominant in the zooplankton of Arctic seas. We hypothesized that the anticipated warm-
ing in the Arctic might have different effects on the arctic and boreal species. The effect of temperature on egg
production rate (EPR) in these species at temperatures of 0, 2.5, 5, 7.5, and 10C under contrasting feeding con-
ditions was assessed in 5-day-long experiments. The EPR of the fed C. finmarchicus increased with temperature
over the entire tested range. On the contrary, the EPR of C. glacialis increased only in the range of 0–5C and
dropped with further temperature growth. The difference in the influence of temperature on reproduction of
these two species is statistically significant. Feeding conditions have a considerable effect on the C. finmarchi-
cus EPR. The EPRs of the female C. glacialis that fed or starved for 5 days displayed no significant difference.
These results suggest that the C. finmarchicus EPR increases with temperature under favorable feeding condi-
tions, whereas the C. glacialis EPR decreases at a temperature over 5C independently of the feeding condi-
tions. This allows for prediction of the shift in abundances of these two species in pelagic communities of Arctic
seas in the case of a warming scenario.

DOI: 10.1134/S0001437013040085

Pleiades Publishing home page | journal home page | top

If you have any problems with this server, contact webmaster.