All the traits investigated here have been shown to be genetically correlated with growth rate or size-at-age in fish species [egg volume (Su et al. 2002), size-at-hatch and larval viability (Munch et al. 2005), vertebral number (Ando et al. 2008), growth efficiency (Henryon et al. 2002), food consumption rate (Kause et al. 2006)].
It is when they reach five years in age that fish living in the marine environment move offshore to deeper reefs, returning to the rivers to spawn, as they cannot complete their life cycle in the ocean.
However, GSI, which is a fairly accurate estimator of annual reproductive investment when gonadic biomass constitutes the vast majority of annual reproductive investment (Diana 1983; Lester et al. 2004), may increase with age in some fish species (Roff 1983; Heino and Kaitala 1999).
These results are consistent with the observational data discussed in the introduction that the size and age of fish in harvested populations have decreased.
To study hair mercury concentrations among women of reproductive age in relation to fish intake in Ontario, Canada.
This difference may reflect the length of ATR exposure or the older age of fish examined in our study.
Mean log-length and log-weight did not differ significantly (p > 0.37) within each lake from 1996/97 (overall means of 11.9 ± 3.6 cm and 25.79 ± 22.00 g, respectively) to 2006/07 (12.2 ± 3.4 cm and 26.50 ± 21.56 g), but there were some differences in fish age, condition, growth, and δN (Table 1; Tables S4 and S5, Supporting Information).
Bidder [ 18] tried to explain aging in terms of determinate adult body size, as opposed to the absence of aging that he assumed in fish with indeterminate, indefinite, adult body growth.
Individuals have been documented to reach eight years of age, but fish in the 0-5 age range comprise the majority of individuals in studied populations [ 48– 50].
Fish older that age-0 were aged using size distributions from known-age fish (age-0) captured in the autumn.
The weight (age) of fish does not influence the content of BP in the muscular tissue of fish.
