title: Spatial segregation within the spawning migration of North Eastern Atlantic mackerel (Scomber scombrus) as indicated by juvenile growth patterns.
abstract: A comparison of growth data (fish length) with latitude shows that southern juvenile mackerel attain a greater length than those originating from further north before growth ceases during their first winter. A similar significant relationship was found between the growth in the first year (derived from the otolith inner winter ring) and latitude for adult mackerel spawning between 44°N (Bay of Biscay) and 54°N (west of Ireland). These observations are consistent with spatial segregation of the spawning migration; the further north that the fish were hatched, the further north they will tend to spawn. No such relationship was found in mackerel spawning at more northerly latitudes, possibly as a consequence of increased spatial mixing in a more energetic regime with stronger currents. This study provides previously lacking support for spawning segregation behaviour among North East Atlantic mackerel--an important step towards understanding the migratory behaviour of mackerel and hence the spatiotemporal distribution dynamics around spawning time.
authors.affiliation: DTU AQUA-National Institute of Aquatic Resources, Technical University of Denmark, Charlottenlund, Denmark. Tej@aqua.dtu.dk
authors.forename: Teunis
authors.initials: T
authors.lastname: Jansen
authors.forename: Andrew
authors.initials: A
authors.lastname: Campbell
authors.forename: Thomas
authors.initials: T
authors.lastname: Brunel
authors.forename: Lotte
authors.initials: L
authors.lastname: Worsøe Clausen
mesh_terms: D025041:Animal Migration; D000818:Animals; D001267:Atlantic Ocean; D049628:Body Size; D010473:Perciformes / Q000254:growth & development* / Q000502:physiology*; D013037:Spatial Behavior