pelAcousticsCal: routine calibration of industry vessels
The Dutch pelagic fishing industry (PFA) actively collects acoustic and biological data to expand the knowledge base and enable better management of fish stocks.In addition, the sector uses this data to develop more selective fishing methods. However, for the use of the acoustic data collected by commercial trawlers (e.g. pelAcousticsAI project), there is the need for the calibration of echosounders. Such calibration is essential for scientific application as it allows the echosounders to measure absolute scattering levels as opposed to relative measurements. The calibration of echosounders is typically done using specific target spheres, an operation that can be time-consuming and in turn impractical onboard commercial vessels. Whilst such calibration trials have been conducted on numerous vessels from the PFA fleets, the echosounder of several vessels remains uncalibrated. Moreover, it is good practice that calibration values are updated regularly. This study aims to address the need for calibrating echosounders on commercial trawlers to enhance the usability of acoustic data for scientific applications and the work undertaken is three-fold. First, the results of two new sphere calibrations onboard PFA trawlers are reported, together with a summary of recent sphere calibration trials. Second, an alternative calibration method using seabed echoes is developed and tested and proxies for calibration gains are derived. Third, the feasibility of calibrating vessels during fishing trips is explored with selected data sets. Overall, the alternative calibration methods presented here have potential and could be essential methods to ensure the calibration of the whole PFA fleet, thereby improving the accuracy of acoustic data.
| Main Authors: | , , |
|---|---|
| Format: | External research report biblioteca |
| Language: | English |
| Published: |
Wageningen Marine Research
|
| Subjects: | Life Science, |
| Online Access: | https://research.wur.nl/en/publications/pelacousticscal-routine-calibration-of-industry-vessels |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | The Dutch pelagic fishing industry (PFA) actively collects acoustic and biological data to expand the knowledge base and enable better management of fish stocks.In addition, the sector uses this data to develop more selective fishing methods. However, for the use of the acoustic data collected by commercial trawlers (e.g. pelAcousticsAI project), there is the need for the calibration of echosounders. Such calibration is essential for scientific application as it allows the echosounders to measure absolute scattering levels as opposed to relative measurements. The calibration of echosounders is typically done using specific target spheres, an operation that can be time-consuming and in turn impractical onboard commercial vessels. Whilst such calibration trials have been conducted on numerous vessels from the PFA fleets, the echosounder of several vessels remains uncalibrated. Moreover, it is good practice that calibration values are updated regularly. This study aims to address the need for calibrating echosounders on commercial trawlers to enhance the usability of acoustic data for scientific applications and the work undertaken is three-fold. First, the results of two new sphere calibrations onboard PFA trawlers are reported, together with a summary of recent sphere calibration trials. Second, an alternative calibration method using seabed echoes is developed and tested and proxies for calibration gains are derived. Third, the feasibility of calibrating vessels during fishing trips is explored with selected data sets. Overall, the alternative calibration methods presented here have potential and could be essential methods to ensure the calibration of the whole PFA fleet, thereby improving the accuracy of acoustic data. |
|---|