Promising results with biodegradable gillnets in the Norwegian winter cod fishery in February–March 2025

August 2nd, 2026 |

Biodegradable fishing gear Gillnetting

We have published a new article in the Journal for Nature Conservation based trials comparing monofilament gillnets made from the biodegradable PBSA material (polybutylene succinate-co-adipate) and conventional nylon (polyamide6.6) with the same mesh size and overall dimensions. The results are based on data collected within Research area 3 of Dsolve.

Biodegradable plastic materials are being tested in different fisheries for reducing marine plastic pollution and continuous capture by abandoned, lost, or otherwise discarded gillnets. These earlier trials (including research by Dsolve) have shown varying results regarding the fishing efficiency of biodegradable gillnets, including reductions of efficiency over time they are being used. Therefore, this study aimed at exploring the fishing efficiency of gillnets made of biodegradable polybutylene succinate-co-adipate (PBSA) material at different time points during sea trials in the Northeast Arctic cod (Gadus morhua) fishery.

In the first trial series, eight PBSA nets and eight nylon nets, both with a twine diameter of 0.7 mm, were compared over 20 deployments. Since PBSA has a lower breaking strength than nylon, we wanted to investigate the use of a thicker PBSA monofilament. Therefore, in the second trial series, 10 PBSA nets with a twine diameter of 0.8 mm were compared with 10 nylon nets with a twine diameter of 0.7 mm over 19 deployments.

The results in both experiments showed that the average fishing efficiency between biodegradable PBSA and nylon gillnets was similar regarding the total amount of cod captured over the whole experiment during February – March 2026. However, the results also showed that the catches in gillnets of both materials were clearly length-dependent, where PBSA gillnets retained less of larger-sized cod (> around 95 cm), while having similar or higher catch rates of smaller cod (around < 95 cm). This reduction in catch efficiency of larger cod for the PBSA gillnets increased when they were used over the fishing season compared to the initial performance with gillnets of new materials that had not been exposed to fisheries (first six deployments). This reduction in larger cod may result in potential reduction in overall revenue for the industry compared to the nylon gillnet catch value; however, this result differed among the deployments (i.e., 1.1 – 3.1% reduction in income).

These results showed that improvements in long-term catch efficiency and durability are still needed for a commercial application of PBSA gillnets. At the same time, biodegradable gillnets remain an important alternative for reducing ghost fishing and marine plastic pollution from ALD gillnets, since there is a need to balance the short-term economic performance with long-term environmental sustainability – including reduced ghost fishing and marine plastic pollution among others.

Link to the paper is here: Use of biodegradable gillnets for resource and marine environment conservation: assessing the potential application in Northeast Arctic cod (Gadus morhua) fisheries - ScienceDirect