FN Archimer Export Format
PT J
TI Effects of sampling intensity and biomass levels on the precision of acoustic surveys in the Mediterranean Sea
BT 
AF BARRA, Marco
   BONANNO, Angelo
   HATTAB, Tarek
   SARAUX, Claire
   IGLESIAS, Magdalena
   LEONORI, Iole
   TICINA, Vjekoslav
   BASILONE, Gualtiero
   DE FELICE, Andrea
   FERRERI, Rosalia
   MACHIAS, Athanassios
   VENTERO, Ana
   COSTANTINI, Ilaria
   JURETIC, Tea
   PYROUNAKI, Maria Myrto
   BOURDEIX, Jean-Herve
   GASPAREVIC, Denis
   KAPELONIS, Zacharias
   CANDUCI, Giovanni
   GIANNOULAKI, Marianna
AS 1:1;2:2;3:3;4:3,4;5:5;6:6;7:7;8:2;9:6;10:2;11:8;12:5;13:6;14:7;15:9;16:3;17:7;18:9;19:6;20:9;
FF 1:;2:;3:PDG-RBE-MARBEC-LHM;4:PDG-RBE-MARBEC-LHM;5:;6:;7:;8:;9:;10:;11:;12:;13:;14:;15:;16:PDG-RBE-MARBEC-LHM;17:;18:;19:;20:;
C1 National Research Council (CNR), Institute of Marine Sciences, SS Naples, Italy
   National Research Council (CNR), Institute for the study of the anthropic impacts and sustainability in the marine environment, SS Capo Granitola, Campobello di Mazara, TP, Italy
   MARBEC, Univ Montpellier, CNRS, Ifremer, IRD, Avenue Jean Monnet, Sète, France
   IPHC, DEPE, CNRS-Université de Strasbourg, UMR7178, 23 rue du Loess, 67037 Strasbourg, France.
   Instituto Español de Oceanografía, Centro Oceanográfico de Baleares, Muelle de Poniente s/n, 07015 Palma de Mallorca, Spain
   National Research Council (CNR), Institute of Marine Biological Resources and Biotechnologies, Largo Fiera della Pesca, 1 60125 Ancona, Italy
   Institute of Oceanography and Fisheries-Split Set. Ivana Meštrovica, 63, 21000 Split, Croatia
   Hellenic Centre for Marine Research (HCMR), Institute of Marine Biological Resources and Inland Waters, P.O. Box 712, 19013, Anavyssos, Attiki, Greece
   Hellenic Centre for Marine Research (HCMR) , Institute of Marine Biological Resources and Inland Waters, Thalassocosmos Gournes, Heraklion, Crete, Greece
C2 CNR ISMAR, ITALY
   CNR IAS, ITALY
   IFREMER, FRANCE
   CNRS, FRANCE
   IEO, SPAIN
   CNR IRBIM, ITALY
   INST OCEANOG & FISHERIES, CROATIA
   HELLENIC CTR MARINE RES, GREECE
   HELLENIC CTR MARINE RES, GREECE
SI SETE
SE PDG-RBE-MARBEC-LHM
UM MARBEC
IN WOS Ifremer UMR
   DOAJ
   copubli-france
   copubli-europe
IF 3.016
TC 2
UR https://archimer.ifremer.fr/doc/00748/85994/91208.pdf
   https://archimer.ifremer.fr/doc/00748/85994/91209.pdf
LA English
DT Article
CR PELMED - PELAGIQUES MEDITERRANÉE
DE ;Acoustic survey;spatial sampling efficiency;density-dependent effects;Mediterranean Sea
AB Acoustic surveys represent the standard fishery-independent method worldwide for evaluating the biomass and spatial distribution of small pelagic fish populations. Considering the peculiarities of the spatial behaviour of pelagic fishes, the efficiency of the survey design in determining their biomass and spatial distribution is related to the ability to capture the portion of the patches accounting for a larger part of the total biomass. However, the spatial structure of the patches could be strongly influenced by ecosystem characteristics as well as by changes in total biomass related to a density-dependent mechanism. This is of particular interest for anchovies and sardines, which are known for their wide fluctuations and high sensitivity to the environment. In this study, we analysed the efficiency of acoustic surveys targeting European anchovies (Engraulis encrasicolus) and European sardines (Sardina pilchardus) in 10 different areas of the Mediterranean Sea spanning three years of different biomass levels. Using the geostatistical coefficient of variation (CVgeo) of the average occurrence probability of high/medium density values, we showed different patterns in terms of survey design efficiency among areas and species. Anchovies usually showed a lower CVgeo than sardines in the Alboran Sea. In 4 out of 20 cases, CVgeo values showed a consistent decrease with increasing biomass, while in the remaining cases, the CVgeo did not follow any clear pattern, suggesting the presence of important environmental effects. Higher survey design efficiency was found in highly productive sectors influenced by river run-off, allowing us to hypothesize that higher productivity along with the presence of well-localized enrichment mechanisms could favour a spatially consistent distribution and coherent organization of fish populations, leading to higher precision estimates with a given transect design. While most surveys displayed CVgeo close to 10% or less even at low biomass, indicating generally good performances of the survey design, a few areas exhibited higher CVgeo, yielding a potential need to decrease the intertransect distance, always keeping in mind that any survey should be as synoptic as possible. 
PY 2021
SO Mediterranean Marine Science
SN 1108-393X
PU Natl Centre Marine Research
VL 22
IS 4
UT 000744169400002
BP 769
EP 783
DI 10.12681/mms.26100
ID 85994
ER

EF