Characteristics and perfonnance of the fishing gears used for demersal stock assessment in Jtaly have been measured. This work was done in collaboration with all the eleven teams involved in such assessment. Trips were done on 13 different fishing vessels, where 15 gears were measured for a total of 57 hauls. The parameters measured on the gears were: door spread, net horizontal opening at the wing tips, net vertical opening at the bosom centre, net speed in respect to water. Total warp loads were measured on board. Data on characteristics of the vessels and of the fishing gears used (door dimensions, line lengths, number and dimensions offloats, meshes and panels) were also collected. All the data were analysed to show their relationships. Functions between the door spread, the horizontal and vertical net opening from one side and the warp length from the other side, were computed. The aim was to enable the estimation of such openings for other hauls made with the same gears tested. Moreover, to enable these estimations also for gear not tested, predictive models were realized on the basis of the knowledge of some parameters, which can be obtained without the necessity of specific sea tests.
Caratteristiche e prestazioni delle attrezzature a strascico impiegate per la valutazione delle risorse demersali in Italia
Loris FIORENTINI;
1994
Abstract
Characteristics and perfonnance of the fishing gears used for demersal stock assessment in Jtaly have been measured. This work was done in collaboration with all the eleven teams involved in such assessment. Trips were done on 13 different fishing vessels, where 15 gears were measured for a total of 57 hauls. The parameters measured on the gears were: door spread, net horizontal opening at the wing tips, net vertical opening at the bosom centre, net speed in respect to water. Total warp loads were measured on board. Data on characteristics of the vessels and of the fishing gears used (door dimensions, line lengths, number and dimensions offloats, meshes and panels) were also collected. All the data were analysed to show their relationships. Functions between the door spread, the horizontal and vertical net opening from one side and the warp length from the other side, were computed. The aim was to enable the estimation of such openings for other hauls made with the same gears tested. Moreover, to enable these estimations also for gear not tested, predictive models were realized on the basis of the knowledge of some parameters, which can be obtained without the necessity of specific sea tests.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
