FN Archimer Export Format
PT J
TI Effects of density-dependent and stochastic processes on the regulation of cod populations
BT 
AF FROMENTIN, Jean-Marc
   MYERS, Ransom
   BJORNSTAD, Ottar
   STENSETH, Nils
   GJOSAETER, Jakob
   CHRISTIE, Hartvig
AS 1:;2:;3:;4:;5:;6:;
FF 1:PDG-DRV-RH-LSETE;2:;3:;4:;5:;6:;
C1 Univ Oslo, Dept Biol, Div Zool, N-0316 Oslo 3, Norway.
   Inst Marine Res, Flodevigen Marine Res Stn, N-4817 His, Norway.
   Norwegian Inst Nat Res, Sentrum, N-0105 Oslo, Norway.
   IFREMER, Dept Resources Halieut, F-34203 Sete, France.
   Dalhousie Univ, Dept Biol, Halifax, NS B3H 4J1, Canada.
   Natl Ctr Ecol Anal Synth, Santa Barbara, CA 93101 USA.
C2 UNIV OSLO, NORWAY
   INST MARINE RES, NORWAY
   NORWEGIAN INST NAT RES, NORWAY
   IFREMER, FRANCE
   UNIV DALHOUSIE, CANADA
   NATL CTR ECOL ANAL SYNTH, USA
SI SETE
SE PDG-DRV-RH-LSETE
IN WOS Ifremer jusqu'en 2018
   copubli-europe
   copubli-int-hors-europe
IF 3.704
TC 99
UR https://archimer.ifremer.fr/doc/2001/publication-712.pdf
LA English
DT Article
DE ;Stochastic survival, juvenile;Observation errors;Mortality, direct density dependent;Mortality, delayed density dependent;Gadus morhua;Fjord;Cod population dynamics;Bottom flora coverage
AB We analyzed 136 time series (covering from 44 to 73 yr) of juvenile cod to estimate the level of direct and delayed density-dependent mortality (DDM) of 11 populations from the Norwegian Skagerrak coast. The parameters were estimated using a modeling approach that explicitly incorporates observation errors, so that we could quantify the density-independent (stochastic) variation in the survival of juvenile cod. Moderate to strong levels of DDM (direct or delayed) were estimated in eight of the 11 populations. Variability in the 0-group (corrected for observation errors) appeared to be large for most of the populations. Substantial stochastic variability in postsettlement survival was also detected in some areas, indicating that stochastic factors are not only important for egg and larval stages, as stated by the match-mismatch hypothesis, but also for juveniles. We show that the variability in these coastal populations is not only regulated as a function of the strength of DDM processes, but also as an interaction between DDM processes and stochastic factors. We finally postulate that local and regional differences in the strengths of the density-dependent and stochastic processes are related to differences in the quantity and quality of the bottom flora coverage, which govern both food availability and shelter for juveniles.
PY 2001
PD FEB
SO Ecology
SN 0012-9658
PU Ecological Society of America
VL 82
IS 2
UT 000167064100021
BP 567
EP 579
ID 712
ER

EF