FN Archimer Export Format
PT C
TI Variability and controls of otolith growth in the anchovy of the Bay of Biscay
BT 
AF PETITGAS, Pierre
   GRELLIER, Patrick
   DUHAMEL, Erwan
   MASSE, Jacques
   DORAY, Mathieu
AS 1:1;2:1;3:1;4:1;5:1;
FF 1:PDG-RBE-EMH;2:PDG-RBE-EMH;3:PDG-RBE-STH-LTBH;4:PDG-RBE-EMH;5:PDG-RBE-EMH;
C1 Ifremer, France
C2 IFREMER, FRANCE
SI NANTES
   LORIENT
SE PDG-RBE-EMH
   PDG-RBE-STH-LTBH
UR https://archimer.ifremer.fr/doc/00114/22550/20236.pdf
LA English
DT Proceedings paper
DE ;Anchovy;Biscay;Otoliths;Growth;Metapopulation
AB Individual fish growth depends on internal population factors such as phenotypic variability as well as external factors such as past environmental conditions (temperature, food) and selective mortality (predation or fishing). In the anchovy, growth in the first year is key to population dynamics as it determines the potential energy allocated to reproduction as well as the capacity to occupy off-shore habitats. Further, in the recent past, the anchovy in the bay of Biscay has experienced collapse and recovery and the role played by growth in this history is unknown. Since 2001 with the spring acoustic survey series PelGas, we have monitored individual fish growth by measuring in the otolith the increments between annual rings, in addition to age determination. These data now allow to analyse the growth patterns in the population as well as the effects of environmental parameters and fishing on the apparent growth of individuals. We show that growth is related to a spatial pattern where smaller and lower growing individuals are more coastal than off-shore larger and faster growers. We evidence a temperature effect on the growth pattern where warm years are also those of faster growth. In contrast, fishing does not seem to affect the apparent growth. We also account for the variability of growth between individuals, which has stayed high throughout the series. The study implies a spatial substructure and segregation in this population where particular habitats could have played a fundamental role for the recovery of the population after its collapse.
PY 2012
CT ICES CM 2012/J:18
ID 22550
ER

EF