FN Archimer Export Format
PT J
TI Genetic population structure of anchovy (Engraulis encrasicolus) in North-western Europe and variability in the seasonal distribution of the stocks
BT 
AF Huret, Martin
   Lebigre, Christophe
   Iriondo, Mikel
   Montes, Iratxe
   Estonba, Andone
AS 1:1;2:1;3:2;4:2;5:2;
FF 1:PDG-RBE-STH-LBH;2:PDG-RBE-STH-LBH;3:;4:;5:;
C1 IFREMER, STH/LBH, B.P. 70, Plouzané, 29280, France
   Department of Genetics, Physical Anthropology and Animal Physiology, University of Basque Country (UPV/EHU), Leoia, Spain
C2 IFREMER, FRANCE
   UNIV PAIS VASCO EHU, SPAIN
SI BREST
SE PDG-RBE-STH-LBH
IN WOS Ifremer UPR
   copubli-europe
IF 2.422
TC 12
UR https://archimer.ifremer.fr/doc/00630/74178/73793.pdf
LA English
DT Article
CR CAMANOC
   CGFS : CHANNEL GROUND FISH SURVEY
   EVHOE EVALUATION HALIEUTIQUE OUEST DE L'EUROPE
   INTERNATIONAL BOTTOM TRAWL SURVEY (IBTS)
   PELGAS
BO Thalassa
DE ;European anchovy;English channel;Single nucleotide polymorphism;Spawning site fidelity;Quotient plot;Ecotype
AB A prerequisite in fisheries management is to identify biological meaningful delineations of stocks, the fundamental exploited units. The European anchovy is one such species in need to better identify stock boundaries. Indeed, despite a spawning aggregation behaviour both in the southern Bay of Biscay and southern North Sea in spring and summer, it has a seemingly continuous distribution in autumn across a broad region ranging from the Bay of Biscay to the northern North Sea including the English Channel, thus with potential mixing of the spawning units. We therefore used genetic markers (single nucleotide polymorphisms) to quantify the degree of gene flow between the currently managed fish stock of the bay of Biscay and northern areas of European anchovy’s distribution. Our results confirm the clear distinction between the Bay of Biscay and northernmost populations, with assignment of all English Channel samples to the latter. We also found a clear overall pattern of isolation by distance that resulted primarily from an increasing differentiation with geographic distance in the Northern group magnified by the lack of gene flow with the anchovies of the Bay of Biscay. The small reduction in gene diversity towards northern latitudes may indicate partial isolation of the leading-edge component of the Northern population. Quotient plots relating anchovy’s distribution to environmental covariates showed that anchovies sampled in autumn in the English Channel originate from the summer spawning aggregation in the warm, low saline and plankton rich south-eastern North Sea. This change in the seasonal distribution of the northern population mimics, but in opposite direction, the one of the Bay of Biscay where anchovy spread towards the north from the spawning habitat in the south-eastern bay. The encounter, without mixing, of the two populations west of Brittany in autumn suggests strong spawning site fidelity. Finally, we identified for the first time anchovies belonging to the estuarine ecotype in the Loire estuary. Our results therefore support current management units, yet with some uncertainties for the catches in the transition zones between the Bay of Biscay and the English Channel, and within river plumes in the vicinity of estuaries hosting the estuarine ecotype. 
PY 2020
PD SEP
SO Fisheries Research
SN 0165-7836
PU Elsevier BV
VL 229
UT 000539099200023
DI 10.1016/j.fishres.2020.105619
ID 74178
ER

EF