Publication on data.gouv.fr
Species and habitats - Raja montagui - All ages Male - Multi-annual abundance in July during BTS (1989-2006)
Biologic data have been expressed in abundance (numbers or density values (nbr/km²)) and always required to be log-transformed using a log10(x+1) transformation.
The standard survey has a total of approximately 100 tows or stations (75 are in ICES division VIId,25 are in ICES division Ivc). A commercial 4m beam trawl fitted with a chain mat, flip-up ropes, and a 40 mm cod-end liner is used.The gear is towed at 4 knots (ground speed) for 30 minutes on a warp length appropriate to the depth of water. At each sampling station (only daylight), all the fish species are sorted, weighed, counted and measured.
Purpose: not specified