As part of the SARDINHA2020 project, the SLIPPING-21S campaign is underway, with the objective of assessing, in a natural environment, the survival of sardines after net unplugging or unraveling (slipping in English).
Slipping is a unique form of rejection practiced in siege fishing, usually associated with high fish survival. When the catch daesn´t interest the fisherman due to market issues, catch limits or size, it is released by maneuvering the net so that it “slips” over the flotation line (hence the English term slipping), always remaining inside of water until release. This practice has been considered of minimum harm, but several recent studies based on experiences in captivity, indicate that mortality can be high and point out ways to reduce it.
The Sardine species is often the target of slipping in the enclosure, especially during periods of restrictions on its capture, as has happened in recent years.
Experiment started on April 28, when the trawler Rio Odiel made a bid for sardines and simulated the operation of unmasking the net. About 800 sardines were transferred, in two moments of net collecting, with the net still wide and with the net tight for a few minutes, to two experimental rafts anchored off the coast of Olhão. The rafts will continue to be monitored daily by IPMA´s team until May 5th.
For this procedure, IPMA had the support of Olhãopesca, Recreational Port of Olhão and Tunipex.