MSc Defense – Adepa Akosua Anyang

Master’s Thesis Defense by:

Adepa Akosua Anyang

September 22, 2023 at 1:00 pm
AERL 220 / Zoom

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Meeting ID: 667 3561 2393
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Projecting catch potential for British Columbia First Nations under climate change and fisheries management scenarios.

Human activities, particularly climate change, over-exploitation, and marine pollution such as plastic, impact marine biodiversity is negatively impacting seafood availability that are important as a source of food and nutrient for many coastal communities. Coastal First Nations in British Columbia are inherently connected to marine life through fishing. Thus, it’s crucial to explore climate change and fisheries’ effects on fish stocks that are essential for First Nations’ food and culture. This study assessed the potential seafood availability from 24 marine species that are important for four First Nations in British Columbia: Skidegate, ‘Namgis, Tla’amin, and Nuxalk (Bella Coola). This study estimated that in 2018, the marine food harvest for Tla’amin, Bella Coola, Skidegate, and ‘Namgis totalled approximately 28.3, 27.0, 27.9, and 19.0 tonnes, respectively. Salmon, especially sockeye salmon (Oncorhynchus nerka), formed a significant portion (about 80 tonnes) of finfish marine food. Abalone (Haliotis kamtschatkana), barnacles (Balanus glandula), trout (Oncorhynchus clarkii clarkii), scallops (Patinopecten caurinus), sea urchin (Strongylocentrotus spp), and sea cucumber (Prastichopus calfornicus) had the lowest potential harvest, totalling 9 kg. Using a Dynamic Bioclimate Envelope model, the study projected potential changes in seafood availability, for the four studied coastal First Nations under climate change and fishing scenarios. Specifically, the model projected declines in seafood availability by 203 and 763 tonnes by 2090 relative to 2018 under the low and high greenhouse gas emissions scenarios, respectively. Sockeye salmon, chinook salmon (Oncorhynchus tshawytscha), and eulachon (Thaleichthys pacificus) were most sensitive to climate change, with projected declines of 421, 144, and 81 tonnes, respectively, by 2090 under the high emissions scenario. In contrast, pink salmon (Oncorhynchus gorbuscha), Nuttall’s cockle (Clainocardium nuttallii), and dolly varden trout (Salvelinus malma malma) were more resilient to climate change. In total, Tla’amin faced the greatest risk of climate change on potential seafood availability, with an average of 15.8% decline under the higher emissions scenario while Skidegate was projected to be the least affected, with a 7.1% to 10.3% decline by 2090 relative to 2018. The effect of fishing scenarios on seafood availability was shown to play a significant role in seafood availability. Under a ‘conservation-focused’ scenario i.e., fishing level in British Columbia waters is managed at half of the level at maximum sustainable yield (MSY), the model projected 58.5% higher seafood availability to the four coastal First Nations by 2090 relative to 2018, compared to managing at MSY. In contrast, the fishing level at 50% above MSY led to a 55.5% decrease in seafood availability. However, even with conservation-focused strategies, seafood availability was projected to decline due to climate change. The study underscores the intricate relationship between climate change, fisheries management, and seafood availability for coastal First Nations in British Columbia. Different impacts of climate change and fisheries management scenarios on each community highlight the need for a collaborative approach to climate adaptation. The research suggests a context-based strategy, incorporating First Nations’ needs, as a necessary foundation for effective climate adaptation and fisheries management.

Examining Committee
Chairperson (TBA)
Dr. William Cheung
Dr. Daniel Pauly
Dr. Rashid Sumaila