Validity of inferring size-selective mortality and a critical size limit in Pacific salmon from scale circulus spacing.

ABSTRACT: Size-selective mortality owing to lack of energy reserves during the first marine winter has been suggested to be a result of juvenile salmon failing to reach a critical size or condition by the end of their first marine summer and not surviving the following winter due to this presumed energy deficit. This hypothesis implies strong size dependency of mortality, and is subject to empirical data support for acceptance. Scale circulus spacing has been interpreted as an index for body size, and we reviewed the effect of size-selective mortality with a knife-edge mortality function on descriptive statistics for a scale circulus spacing index (SCSI). In order to invoke size selection as an important driver of mortality during the first year of ocean rearing, it is necessary to demonstrate not o

SUBMITTER: Beacham TD 

PROVIDER: S-EPMC6019399 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature