Premium
The influence of temperature on the stage at hatch of laboratory reared Gadus morhua and implications for comparisons of length and morphology
Author(s) -
Jordaan A.,
Hayhurst S. E.,
Kling L. J.
Publication year - 2006
Publication title -
journal of fish biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.672
H-Index - 115
eISSN - 1095-8649
pISSN - 0022-1112
DOI - 10.1111/j.0022-1112.2006.00857.x
Subject(s) - biology , gadus , larva , hatching , yolk sac , zoology , gadidae , developmental stage , yolk , atlantic cod , fishery , fish <actinopterygii> , ecology , embryo , developmental psychology , psychology
A staging table for yolk‐sac larvae of Atlantic cod Gadus morhua was developed and applied to determine the development stage at hatch. Larvae ( n = 20) were sampled during the period from 50% hatch to first‐feeding from four temperature treatments ( c . 2, 4, 8 and 12° C). Data recorded included standard length, development stage, yolk‐sac area and evidence of feeding by larvae. The results indicated that the stage of development at hatch was positively correlated to larval size. Furthermore, developmentally based changes in morphology shortly after hatch reduced much of the initial difference in size, although some difference still existed. No relationship between size at hatch and the incidence of first‐feeding larvae was found. Based on these observations, it is recommended that the development stage of hatching larvae be reported in studies investigating size and morphological differences when observing individual larval fish that originate from different populations, batches or species.