Spatio-temporal changes in the distribution of benthic organisms at finfish farm sites on the south coast of Newfoundland

• Main Author: Mersereau, Joseph Montague
• Format: Thesis
• Language: English
• Published: Memorial University of Newfoundland 2015
• Subjects: Newfoundland
• Online Access: https://research.library.mun.ca/8341/; https://research.library.mun.ca/8341/1/thesis.pdf

In Newfoundland, assessing benthic community changes associated with organic matter enrichment near finfish farms is challenging because the majority of aquaculture sites are in deep waters, over hard, patchy substrata, where soft sediment sampling methods are ineffective. A promising approach is the use of video surveys to analyze epibenthic characteristics, including taxa that are indicative of organic matter enrichment, Beggiatoa spp. and OPC. Here, I compare seafloor biotic and abiotic characteristics on temporal and spatial scales over 2 years and at six locations. Benthic organisms and indicators were identified and evaluated in relation to distance to cage, aquaculture production status and environmental conditions. Abundance and percent cover of the benthos, with the exception of bio-indicators, was higher in non-production sites compared to the production and fallow sites, with minimal changes over time. Organic enrichment via aquaculture can lead to long term benthic changes (> 1 year) on hard substrata.