FN Archimer Export Format
PT J
TI Estimating gear efficiency in a combined acoustic and trawl survey, with reference to the spatial distribution of demersal fish
BT 
AF DORAY, Mathieu
   MAHEVAS, Stephanie
   TRENKEL, Verena
AS 1:1;2:1;3:1;
FF 1:PDG-DOP-DCN-EMH;2:PDG-DOP-DCN-EMH;3:PDG-DOP-DCN-EMH;
C1 IFREMER, EMH, F-44311 Nantes 03, France.
C2 IFREMER, FRANCE
SI NANTES
SE PDG-DOP-DCN-EMH
IN WOS Ifremer jusqu'en 2018
IF 1.808
TC 15
UR https://archimer.ifremer.fr/doc/00002/11372/7980.pdf
LA English
DT Article
CR CHAPAUV
BO Thalia
DE ;availability;Bay of Biscay;catchability;generalized linear model;geostatistics;hake;vulnerability
AB Few analyses have been performed to estimate the efficiency of trawls targeting demersal fish using the ratio of catches and acoustic densities. In summer 2006, acoustic and fishing data were collected simultaneously over 3 d by three fishing vessels equipped with identical pelagic trawls in the Bay of Biscay. Variography identified moderate spatial autocorrelation in the acoustic backscatter at a mean scale of 3 km, a scale slightly smaller than the mean haul length (3.5 km), indicating that fish horizontal availability did not influence trawl efficiency. Acoustic backscattering densities expressed as nautical area scattering coefficients (NASCs) recorded in the trawled layer were compared with equivalent NASC (ENASC) values calculated from the species composition in the trawl, fish-length structure, and available relationships between target strength and fish length. Estimates of trawl efficiency for hake-dominated trawls were computed as the slopes of the relationships ENASC = 0.008 NASC and ENASC = 0.18 NASC0.31 for trawls made by day and night, respectively. For the whole demersal community, the relationships were ENASC = 0.022 NASC and ENASC = 0.17 NASC0.33 for trawls made by day and night, respectively.
PY 2010
PD MAY
SO Ices Journal Of Marine Science
SN 1054-3139
PU Oxford Univ Press
VL 67
IS 4
UT 000276732500007
BP 668
EP 676
DI 10.1093/icesjms/fsp277
ID 11372
ER

EF