title: Latitudinal Gradient in Otolith Shape among Local Populations of Atlantic Herring (Clupea harengus L.) in Norway.
abstract: Otolith shape analysis of Atlantic herring (Clupea harengus) in Norwegian waters shows significant differentiation among fjords and a latitudinal gradient along the coast where neighbouring populations are more similar to each other than to those sampled at larger distances. The otolith shape was obtained using quantitative shape analysis, the outlines were transformed with Wavelet and analysed with multivariate methods. The observed morphological differences are likely to reflect environmental differences but indicate low dispersal among the local herring populations. Otolith shape variation suggests also limited exchange between the local populations and their oceanic counterparts, which could be due to differences in spawning behaviour. Herring from the most northerly location (69°N) in Balsfjord, which is genetically more similar to Pacific herring (Clupea pallasii), differed in otolith shape from all the other populations. Our results suggest that the semi-enclosed systems, where the local populations live and breed, are efficient barriers for dispersal. Otolith shape can thus serve as a marker to identify the origin of herring along the coast of Norway.
authors.affiliation: Department of Life and Environmental Sciences, University of Iceland, Reykjavík, Iceland.
authors.forename: Lísa Anne
authors.initials: LA
authors.lastname: Libungan
authors.affiliation: Institute of Marine Research, Bergen, Norway; Hjort Centre for Marine Ecosystem Dynamics, Bergen, Norway.
authors.forename: Aril
authors.initials: A
authors.lastname: Slotte
authors.affiliation: Institute of Marine Research, Bergen, Norway.
authors.forename: Åse
authors.initials: Å
authors.lastname: Husebø
authors.affiliation: Institute of Marine Research, Bergen, Norway; Hjort Centre for Marine Ecosystem Dynamics, Bergen, Norway.
authors.forename: Jane A
authors.initials: JA
authors.lastname: Godiksen
authors.affiliation: Department of Life and Environmental Sciences, University of Iceland, Reykjavík, Iceland.
authors.forename: Snæbjörn
authors.initials: S
authors.lastname: Pálsson
mesh_terms: D025041:Animal Migration; D000818:Animals; D001267:Atlantic Ocean; D003433:Crosses, Genetic; D063366:Estuaries; D005260:Female; D005399:Fishes / Q000033:anatomy & histology* / Q000145:classification; D007091:Image Processing, Computer-Assisted; D060106:Lakes; D008297:Male; D015999:Multivariate Analysis; D009664:Norway; D010037:Otolithic Membrane / Q000648:ultrastructure*; D011157:Population Dynamics; D012621:Seasons; D012726:Sexual Behavior, Animal