dc.contributor.author | Heino, Mikko | |
dc.contributor.author | Boukal, David S. | |
dc.contributor.author | Falkenhaug, Tone | |
dc.contributor.author | Piatkowski, Uwe | |
dc.contributor.author | Porteiro, Filipe M. | |
dc.contributor.author | Sutton, Tracey T. | |
dc.date.accessioned | 2012-02-07T08:30:55Z | |
dc.date.available | 2012-02-07T08:30:55Z | |
dc.date.issued | 2008 | |
dc.identifier.citation | This report is not to be quoted without prior consultation with the General Secretary. | no_NO |
dc.identifier.uri | http://hdl.handle.net/11250/102688 | |
dc.description.abstract | Here we present a new technique to study life history variation when only length distributions
of populations are known. Shape of length distribution in a population is to a significant extent
determined by the degree to which an average individual approaches its asymptotic
maximum size. Statistically, the shape of a length can be characterised by its skewness, measuring
the degree of symmetry in the distribution. Positive skew (long right tail) in a length distribution
suggests that relative few individuals survive long enough to approach asymptotic
size in a population, whereas the opposite is true for negative skew (long left tail). With a
simple model of age-size dynamics in a population showing indeterminate growth, we show
that skewness is strongly correlated with the ratio between mortality rate and the growth parameter
k in the von Bertalanffy growth model; this ratio is a dimensionless number that is
one of Beverton’s ‘life history statics’. We demonstrate the new technique with data from
deep-pelagic fishes collected during the 2004 Mar-Eco expedition along the northern Mid-
Atlantic Ridge.
Keywords: Dimensionless numbers, growth trajectory, life-history invariants, mortality | no_NO |
dc.language.iso | eng | no_NO |
dc.publisher | ICES | no_NO |
dc.relation.ispartofseries | ICES CM documents;2008/F:13 | |
dc.subject | growth | no_NO |
dc.subject | vekst | no_NO |
dc.subject | mortality | no_NO |
dc.subject | dødelighet | no_NO |
dc.title | Size structure, age-size dynamics and life history variation | no_NO |
dc.type | Working paper | no_NO |
dc.subject.nsi | VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Fish health: 923 | no_NO |
dc.subject.nsi | VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Fisheries technology: 924 | no_NO |
dc.source.pagenumber | 7 s. | no_NO |