Latitudinal clines in life‐history variables of anadromous brown trout in Europe

Abstract

Based on published data, we reviewed clinal variations in life‐history characteristics of anadromous brown trout Salmo trutta from 102 European rivers at latitudes between 54 and 70° N. Growth rate in fresh water, mean smolt age, mean sea age at first sexual maturity, proportion of repeal spawners among adults, longevity, and length of adult life span exhibited latitudinal clines. Brown trout grew faster in fresh water, smolted and matured younger, lived fewer years but spawned more times in the south than in the north. The life‐history traits studied were often correlated. Longevity, smolt age and sea age at maturity were negatively and smolt length and proportion of repeat spawners among adults were positively correlated with growth rate in fresh water. Longevity was positively correlated with smolt age and sea age at maturity. The latter also increased with increasing smolt age. None of these significant correlations among life history variables, except for those between smolt age and parr growth and proportion of repeat spawners and parr growth, are latitudinal effects. We do not know to what extent the latitudinal variation in life–history traits reflects phenotypic plasticity and to what extent it is caused by inherited differences among populations.

Overwintering and downstream migration of sea trout (Salmo truttaL.) kelts under regulated flows—northern Sweden

“…A latitudinal cline in a number of life history traits (e.g. smolt age and size, smolt run timing) among sea trout has been found, also dependent of river size (LÁ beé-Lund et al, 1989;Jonsson and LÁ bée-Lund, 1993;Jonsson et al, 2001). It might also just reflect the plasticity and variability of this species.…”

Latitudinal trends in adult body size of Dolly Varden, with special reference to the food availability hypothesis

“…In addition, primary productivity may not be an accurate estimate of production that is available to higher trophic levels (see Dodson 1997). In Atlantic salmon and brown trout with alternative life histories, there was no significant relationship between mean adult size and latitude (Jonsson and L'Abee-Lund 1993). Unlike ocean productivity, however, some evidence of strongly negative relationships between growth rate during juvenile stage and latitude and of positive relationships between smolting age and latitude in these species suggests that river productivity increases gradually from north to south in the Northern Hemisphere (Metcalfe and Thorpe 1990;Jonsson and L'Abee-Lund 1993;Yamamoto et al 1999b).…”

Age and Growth of Brown Trout (Salmo trutta) in Six Rivers of the Southern Part of Caspian Basin

“…In addition, brown trout smolt size increases with latitude, probably as an effect of decreasing water temperature towards the north (Jonsson and L'Abée-Lund, 1993;L'Abée-Lund et al, 1989).…”