Acoustic Detection of Abandoned, Lost, and Discarded Fishing Gear (ALDFG)

Abandoned, lost, and discarded fishing gear (ALDFG), also known as ghost gear, is commonly found in our oceans and negatively impacts marine environments and industries. Managing ALDFG in Atlantic Canada has been challenging due to knowledge gaps such as loss rates, impacts of ghost gear, and regulatory barriers for retrieval.

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To address these problems, Coastal Action undertook the Collaborative Remediation of Abandoned, Lost, and Discarded Fishing Gear (ALDFG) in Southwest Nova Scotia project funded by Fisheries and Oceans Canada (DFO)’s Sustainable Fisheries Solutions and Retrieval Support Contribution Program (SFSRSCP).

This project was completed over two years, during 2020 and 2021.
Overall, this project aims to prevent, reduce, and assess ALDFG in Southwest Nova Scotia (Lobster Fishing Areas (LFA's) 33, 34,35 – Nova Scotia only) in a collaborative manner, working with stakeholders including industry, government, non-profit organizations, and academia.

Master's Research Project

To further increase knowledge on lost gear in SWNS, side-scan sonar (SSS) surveys were executed with the Ocean Tracking Network (OTN) and Ocean Frontier Institute (OFI) to verify hotspot areas identified by fishers and DFO’s records in both 2020 and 2021. A preliminary trial survey was completed in Lunenburg in 2020, and a 12 day comprehensive survey was completed in Clark’s Harbour to further understand the advantages and disadvantages of side-scan sonar technology for large-scale retrieval missions.

Results

During the comprehensive survey in Clarks Harbour, 161 potential targets were identified; however, upon a second comprehensive review, 114 targets were confirmed, revealing that many of the initial targets were unlikely to be ALDFG. Based on the expenses calculated, it is estimated to cost CAD $743 to $897 to survey an area of 1 km2 at full coverage

Recommendations

Increasing compliance with ALDFG reporting and that community and fisher intel is extensively and consistently gathered (i.e., focus groups, surveys, personal communications) before retrieval efforts are conducted.
Focus on operating SSS in large-scale retrieval missions where targeted retrieval may be necessary due to sensitive bottom habitats.
Improving the cohesion of SSS missions, detections of lost gear, and follow-up retrieval towing.
Further, we recommend that more knowledge on SSS be made more widely available to retrieval groups before applying this technology.

Research Dissemination

L. Fulton. 2022. Saving Ghost Fishing Gear. Esri Canada GIS Day in Canada. November 14, 2022. Invited Speaker. Virtual Presentation.

L. Fulton. 2022. Collaborative Remediation of Abandoned, Lost and Discarded Fishing Gear in Southwest Nova Scotia. The Canadian Marine Shipping Risk Forum (CMSRF). June 23, 2022. Invited Speaker. Virtual Presentation.

L. Fulton. 2022. Connecting on a Deeper Level: Using StoryMaps to Combine Seafloor Mapping and Local Knowledge. Esri Canada Marine and Inland Waters Forum. June 1, 2022. Invited Speaker. Virtual Presentation

L. Fulton, C.J. Brown, J. McIntyre, A. Smith, T. Walker. 2022. Evaluating the benefits of side scan sonar as a detection method for abandoned, lost, or otherwise discarded fishing gear. GEOHAB Conference 2022. Venice, Italy. May 16 – 20, 2022. Oral Presentation.