caa a22 4500 397550472 CHVBK 20180308164748.0 cr unu---uuuuu 161202e199610 xx s 000 0 eng 10.1006/jmsc.1996.0104 doi (NATIONALLICENCE)oxford-10.1006/jmsc.1996.0104 Role of the midnight sun: comparative growth of pelagic juvenile cod (Gadus morhua) from the Arcto-Norwegian and a Nova Scotian stock [Elektronische Daten] [Iain M. Suthers, Svein Sundby] Size-at-age of pelagic juvenile cod from the north-east Atlantic off northern Norway was approximately twice that of cod from the north-west Atlantic, off south-western Nova Scotia, Canada. Arcto-Norwegian cod (AN, 17-48 mm standard length, SL, 34-90 d post-hatch), were sampled in July 1988 with a capelin pelagic trawl, while south-west Nova cod (NAFO region 4X, 7-32 mm SL and 32-105 d post-hatch) were sampled in May-June 1985-1986 with a Tucker trawl. Growth over the previous 14 d, back-calculated from otolith daily growth increments was 0.71 mm d−1 and 0.33 mm d−1 for AN and 4X cod respectively. Within and between stocks, water temperature and zooplankton biomass were significantly correlated with the 14 d index (linear model, r2=0.42), but an ANCOVA model comparing the AN and 4X regions was highly significant (r2=0.71), indicating additional factors. Gear selection was not found to be responsible. While genetic factors could produce this result, there is 48% more time during May-July for visual feeding north of the 71°N latitude off Norway compared with 43°N off eastern Canada, using the light intensity threshold for larval cod feeding. Our hypothesis of light-limited feeding opportunity is consistent with a size- and temperature-dependent consumption model, and with aquaculture methods, as well as the necessity for fast growth in the short northern summer for over-winter survival. © 1996 International council for the Exploration of the Sea Articles nationallicence pelagic juvenile cod nationallicence otolith microstructure nationallicence growth nationallicence age nationallicence stock nationallicence population nationallicence light nationallicence photoperiod nationallicence temperature nationallicence prey nationallicence consumption nationallicence model nationallicence Suthers Iain M. Institute of Marine Research, P.O. Box 1870-Nordnes, 5024, Bergen, Norway aut Sundby Svein Institute of Marine Research, P.O. Box 1870-Nordnes, 5024, Bergen, Norway aut ICES Journal of Marine Science Oxford University Press 53/5(1996-10), 827-836 1054-3139 53:5<827 1996 53 icesjms https://doi.org/10.1006/jmsc.1996.0104 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1006/jmsc.1996.0104 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Suthers Iain M. Institute of Marine Research, P.O. Box 1870-Nordnes, 5024, Bergen, Norway aut NATIONALLICENCE 700 1- Sundby Svein Institute of Marine Research, P.O. Box 1870-Nordnes, 5024, Bergen, Norway aut NATIONALLICENCE 773 0- ICES Journal of Marine Science Oxford University Press 53/5(1996-10), 827-836 1054-3139 53:5<827 1996 53 icesjms Metadata rights reserved CC BY-NC-4.0 http://creativecommons.org/licenses/by-nc/4.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-oxford