What can SonarX do

 

 

1      Information about SonarX... 2

1.1       Installation... 2

1.2       Uninstall.. 2

1.3       System requirements.. 2

1.4       License.. 2

1.5       Online help and demonstration... 2

2      Analysis overview.... 2

2.1       Pre-analysis: 2

2.2       Analysis: 3

2.3       Data insight.. 3

2.4       Interpretation: 3

2.5       Presentation: 3

2.6       Noise: 4

2.7       Editors: 4

2.8       File overview and file opening... 4

2.9       Comments.. 4

3      Abundance estimation... 5

3.1       What abundance estimation method should I use and why... 5

3.2       TS distribution?. 6

3.3       Estimation method 1 - Scaling sv / ts or integration... 6

3.4       Method 2 - Echo counting or mean ping... 6

3.5       Method 3 - Trace counting or sailed distance.. 7

3.6       Method 4 – Catch statistics and ex-situ tracked targets (Catch, tracks)  7

 

 

 

 

 

 

 

1            Information about SonarX

1.1      Installation

No installation procedure is needed to run the program. Download the program file to a separate folder and click on the icon with the mouse is sufficient. To enable help, help files must be downloaded and placed in a subfolder named help. To enable tools, the tool exe files must be downloaded and placed in the same folder as the program file. For those who are have tested the program and are interested in using it, a complete CD with the program, tools, help, additional articles and demo files can be asked for. 

1.2      Uninstall

The program does not temper with the PCs registry, system files or any system directories. Hence, deleting the program folder results in a total clean-up. No trace of the program will then remain on the PC. 

1.3      System requirements

No special requirements.

1.4      License

It is only the converter that needs a licence.  No licence is needed to run the program with the demo files. To use the program with other sonar files than the files applied on the net or on the demonstration CD we can do the conversion for you. To run the converter on a PC, a hardware lock (Dongle) is needed.

1.5      Online help and demonstration

Netmeeting is a program following all window installations. Latest version can be downloaded from http://www.microsoft.com/. With this program we can control SonarX on your PC, explain the program's functions, discuss the sonar data and analysis strategies. We connect simply by typing the IP number in Netmeetings call box. Send an email to hbalk at fys.uio.no to get an IP number and to make an appointment.

 

2            Analysis overview

2.1      Pre-analysis:

·        Single echo detection (Parametric)

·        Bottom detection. (Enhanced with image analysis)

·        Heave correction

·        Manual noise erasing tools

·        Automatic noise reduction systems

·        Noise level detector

·        Fish removal from plankton files

·        Single echo detection (Cross-filter)  (see comment below)

·        Water current detection

2.2      Analysis:

·        Biomass estimation

·        Fish abundance

·        Size distribution

·        Manual tracking

·        Auto tracking

·        Cross-filter tracking (see comment below)

·        Classification and track storing

·        Track statistics

·        Image analysis

2.3      Data insight

·        3D-echogram  

·        Oscilloscope

·        Sample data analyzer 

·        Eckmann threshold

·        SED detections versus off axis angle

·        Graphic all aspect SED and track positions

·        Numerical all aspect SED and track positions

·        Frequency response function,

·        Frequency response maps

·        RGB-echograms.

2.4      Interpretation:

·        Fish database

·        Catch data

·        TS to weight and length calculator

·        Track aspect TS correction

·        De convolution for estimation of size when aspect is unknown

·        Ray tracing for estimation of targets and beam in hor. app.

 

 

2.5      Presentation:

·        Tracked echoes in all aspects

·        Tracks relative to surface and bottom profile (horizontal app.)

·        Tracks relative to water current  (horizontal app.)

·        Photos, drawings and maps

·        Free threshold. 

·        Free color per dB scale

·        Time, ping number, and range

·        Geographical positions and sailed ship distance.  

·        Zoom in and out

·        Layers: Pelagic, Bottom, Free number of sub layers and sub segments 

·        Change TVG view

2.6      Noise:

2.7      Editors:

·        Noise editor

·        Bottom editor

·        Text editors (txt, rtf)

·        Bottom profile editor

·        Water current editor

·        Graphical transducer positioning tools 

 

2.8      File overview and file opening

·        Simple file open dialog presenting only filenames

·        Advanced file open menu presenting filenames with record number, survey description, transect description, additional text description and photos.

·        Graphical presentation of transects in digital maps.

·        Opening of echograms at positions selected graphically from maps

·        Quick file change functions.

 

2.9      Comments

Cross filter detector

The dream of everyone who is dealing with tracking is to see tracks without missing detections and with no surrounding noise. The patented Cross filter detector has been developed to fulfill this dream. Test it with Sonar5-Pro and read about it in the manual chapter 12 and 19.

 

 

 

 

 

3            Abundance estimation

Seven different estimation methods with a variety of options make it possible to apply the best suited estimator to your data set.

The methods are

1.                  sv / ts scaling or echo integration. ts distribution established from catch data. 

2.                  sv / ts scaling or echo integration. ts distribution established from in-situ single echo detections

3.                  sv / ts scaling or echo integration. ts distribution established from in-situ tracked targets

4.                  sv / ts scaling or echo integration. ts distribution established from ex-situ tracked targets

5.                  echo counting based on single echo detections

6.                  echo counting based on tracked single echo detections

7.                  trace counting based on tracked targets

 

Some methods works best with high target density while other methods work better with low density. Noise and robustness to noise and accurate SED detection is another question.

 

3.1      What abundance estimation method should I use and why

 

SonarX Biomass estimation control dialog.

 

Combining the four method options with the source option gives the seven described methods. 

Note that fish baskets can contain single echo detections, tracked targets and catch data.

Read more about the methods in the SonarX manual chapter 8.

Read  more about applying catch data in the SonarX manual chapter 11.

 

There are four different abundance estimation methods. These methods can be combined with single echo detections, catch data, or tracked fish. What to do?

 

3.2      TS distribution? 

All methods need to establish a single target TS-size distribution. The distribution can be established from:

Catch data are applied when one do not trust the size distribution based on single echo detection or tracked single echo detections.

In-situ single echo detections are easy to apply and use.

Tracked targets can be applied a) in order to reduce variability in the TS- size distribution and b) to avoid noise based single echo detections.

Ex-situ tracked targets can be applied if one doesn’t have reliable in-situ obtained tracks or single echo detections. As an example, track herring in an “old” echogram file obtained when the herring was not schooling (night) and then use the tracked herring to obtain a estimate of herring schools during the day. Herring schools are normally surrounded by predators and in-situ single echo detections and tracks should not be trusted.

 

3.3      Estimation method 1 - Scaling sv / ts or integration

Use this method in situations with

 

Abundance is found by dividing the average integrated sv with the in-situ obtained ts distribution based on single echo detections or tracked single echo detection.

Use this method in situations with high fish density when reliable TS-distribution can be obtained.

Tracked fish can be applied as an alternative to single echo detection. Tracking may reduce variability in the TS distribution and exclude noise based detections.

If no reliable TS-distribution can be obtained, consider the catch tracks method.

 

Note that the method assumes constant density within each layer to be analyzed. The method accepts a high portion of multiple echoes.

 

 

3.4      Method 2 - Echo counting or mean ping

Use this method when you have

 

Abundance is found by dividing the number of single echo detections with the number of pings and the beam volume.

The method is

·    sensitive to missing detections from fish due to noise and schooling

·    sensitive to false detections from unwanted targets. This can be avoided with tracking.

·    does not assume constant density in the analyzed layer.

 

Use this method in situations with low fish density, and low mount of false SED detections within the size classes in question.  Both SED and tracked fish can be applied. With tracked fish, the individual echoes in each track are used in the estimate and task for the tracking is to avoid including false detections. 

 

 

3.5      Method 3 - Trace counting or sailed distance

Use this method when you have

Abundance  is found by dividing the number of tracked fish with the monitored water volume.  Water volume is estimated as a wedge along the sailed transect. This method works only with tracked fish. Since the method count tracks  and not single echo detections, this method is more robust to missing detections than the echo counting method. Note that the method need GPS information to find the observation volume

 

 

3.6      Method 4 – Catch statistics and ex-situ tracked targets (Catch, tracks)

Use this method when you have

 

The abundance is estimated in the same way as with the sv/ts scaling method 1, but the ts-distribution is taken either from catch data or for tracked fish tracked at other places or times.

 

This method is the established method for abundance estimation at the sea for large schools. A herring school is as an example, normally too dens to give reliable SED, and single targets seen around the school are often predators.