Investigating the role of fishing gear on plastic pollution: The occurrence of fishing gear-related plastic ingested by Atlantic cod (Gadus morhua) and the fragmentation of polymer ropes

• Main Author: Saturno, Jacquelyn
• Format: Text
• Language: unknown
• Published: Memorial University of Newfoundland 2020
• Subjects: Newfoundland; Canada; Fogo; Fogo Island; atlantic cod; Gadus morhua
• Online Access: https://dx.doi.org/10.48336/dyzx-5k52; https://research.library.mun.ca/15163/

Globally, the fishing industry is one key source of plastic pollution as the majority of fishing gear is made from plastic polymers and regularly used at sea. To study this relationship in an area with high fishing activity, I collected the gastrointestinal tracts (GI) of commercially caught Atlantic cod (Gadus morhua) on Fogo Island, Newfoundland and Labrador and dissected them for ingested plastics. The frequency of occurrence was 1.4% for 216 GI tracts. Two of the three plastic items ingested were bait bags used in cod pots and the third was a thread such as the type found in fishing rope. Following this, I conducted an experiment to test the way different polymer fishing ropes create plastic pollution during use. All polymer types emitted plastics at the same rate (total plastic particles over time), with Polypropylene and Polypropylene-Polyethylene having lasted longer during trials, allowing for more time to pollute. Various sizes and morphologies of plastics were emitted, creating different pollution profiles for each polymer type. Through my investigation of the natural environment and testing fishing gear in-use, this thesis demonstrates that fishing gear is a source of plastic pollution in both fish ingestion and through fragmentation of fishing gear during abrasion with the sea floor in Newfoundland and Labrador, Canada.