Bird-scaring line tension device
Image: Nelson Miranda

The bird-scaring line (BSL) tension device can show whether a BSL is being used by measuring the tension of the BSL as it is towed through the water. The device can also show whether the vessel is night setting.

The device is added into the BSL and records tension continuously, and this is sent wirelessly to a monitor on board the vessel.

Data from more than one vessel can be transmitted to a cloud database and this means a person on shore can see if vessels are using their BSLs.

The device can also be used to show the vessel is night setting because the time is also recorded. 

What to check

To find out if the vessel used the BSL on each set, check the vessel logbook, electronic monitoring footage or observer data, to find out when setting started and ended. Compare this to the data collected by the BSL tension device.

Vessel logbooks, electronic monitoring footage or observer data can be used to to find out where and when fishing took place (latitude and longitude). Check with time of sunset and sunrise to verify if the vessel was night setting on each set.