LSSS Now Open Source: Advancing Marine Research and Resource Management

What is LSSS?

LSSS (Large Scale Survey System) is a specialized software developed for the efficient analysis of large volumes of data from multi-frequency echosounders and sonars. The system enables identification and categorization of marine species such as herring, capelin, and mackerel based on their acoustic signatures. LSSS was developed by researchers at NORCE (formerly Chr. Michelsen Research) in close collaboration with the Institute of Marine Research (IMR), and has been in operational use since 2007. The system builds on ideas from the Bergen Echo Integrator (BEI), which was developed jointly by IMR and CMI (later CMR) from 1988 and used until LSSS took over.

With LSSS, large datasets from acoustic surveys can be interpreted quickly and efficiently, providing an objective basis for stock assessments, resource mapping, and quota setting. The system is used both for daily monitoring of fish stocks and for research on marine ecosystems.

From Closed to Open Code

LSSS is currently used by over 250 users worldwide. Now, the system’s source code is being opened, allowing research communities, management agencies, and technology companies to further develop, customize, and integrate LSSS into their own solutions.

“We hope that opening the source code will lead to even wider dissemination of the knowledge embedded in the system, and strengthen Norway’s and our partners’ international position,” says project leader Rolf Korneliussen, research director in the Acoustics and Observation Methodology group at the Institute of Marine Research.

The release of LSSS comes at a time when international research projects increasingly demand open and transparent analysis tools. This opens new opportunities for collaboration, especially within the International Council for the Exploration of the Sea (ICES), and makes it easier to standardize and compare data across countries and institutions.

How LSSS Works

At the core of LSSS is a modular analysis process where data from multiple acoustic frequencies are processed step-by-step. The system uses an acoustic property library – a collection of “fingerprints” from different species based on their characteristic echoes at various frequencies. By comparing collected data with this library, LSSS can automatically categorize and estimate the abundance of different species in real time or after a survey.

The system also includes advanced tools for bottom detection, noise removal, and automatic detection of fish schools. “This supports manual interpretation, saves time, and makes the analysis less subjective,” explains Inge Kristian Eliassen, senior researcher at NORCE.

Studies show that LSSS provides a very high degree of agreement between automatic and manual interpretation of acoustic data, especially for large fish schools, and significantly reduces uncertainty in stock estimates.

Impact on Research and Management

With LSSS now open source, research communities around the world gain access to a robust tool for acoustic species identification and stock assessment. This can contribute to more objective and efficient resource management and enable analysis of increasingly large datasets from both manned and autonomous vessels.

The system is already known for its user-friendliness and fast processing – one day’s worth of data can be interpreted in about two hours. With open code, LSSS can now be further developed and adapted to new needs, such as broadband data analysis or integration with machine learning and automated observation systems.

The open source code is available on GitHub (link). LSSS has already been available for free download from Marec.no, and courses and support services are offered.