Biofouling Mitigation Treatment on Adjustable Long-Line Systems Affects Cage Movement and Growth of Cultured Eastern Oysters, Crassostrea virginica

Details

• Journal Title:
  Aquaculture Research
• Personal Author:
  Umanzor, Schery ; Jung, Jae Woo ; Dittrich, Muriel ; Kim, Jang K. ; Tomco, Patrick ; Redman, Zachary C. ; Brandhuber, Monica 
• NOAA Program & Office:
  Sea Grant
• Sea Grant Program:
  MDU (Maryland Sea Grant)
• Description:
  Efficient production of the eastern oyster, Crassostrea virginica, requires optimizing grow-out techniques to ensure fast growth and high-quality crops. Biofouling on oyster long-line cages, which can limit flow and reduce animal growth, is typically controlled by various methods to remove or prevent fouling organisms from colonizing cages. However, the effectiveness of these treatments on internal cage conditions and resulting production is poorly understood. Accelerometers were added to stocked oyster long-line cages to understand the physical effects of fouling treatment on the production and quality of cultured oysters in a 2-month study (June-August 2019) when biofouling accumulation was seasonally high. This study compared two biofouling mitigation techniques (24-h weekly desiccation, weekly power washing) against a no-treatment control for three commercial adjustable long-line system (ALS) cage types (Seapa, BST, Hexcyl) to determine how fouling treatment and cage style influence internal jostling, oyster growth, and meat condition. The type of cage used was a stronger effector of biofouling accumulation than the mitigation treatments. Similarly, cage jostling was affected by cage type and mitigation treatment, though there was often a weak, negative correlation between the rate of fouling accumulation and jostling experienced by each cage type. Additionally, oysters in desiccated treatments had a significantly lower average shell height, but a higher condition index (CI) compared to nontreated controls by the end of the field trial, and power-washed cages grew oysters with notably slower shell growth and CI. This suggests that the act of mitigating fouling was likely the cause of the differences in growth rather than the accumulation of fouling itself. We were unable to decipher clear associations between cage jostling and oyster growth performance, requiring the need for more resolved studies over larger spatial scales to better understand the nuances associated with the physical environment and how they relate to oyster growth.
• Keywords:
  American Oyster Aquaculture Fouling Suspension Feeders American Oyster Suspension Feeders Biofouling Crassostrea Virginica Eastern Oyster
• Source:
  Aquaculture Research, 2025, 9238480, 12 pages, 2025
• DOI:
  http://doi.org/10.1155/are/9238480
• Format:
  PDF
• Document Type:
  Journal Article
• Funding:
  Grant no. NA18OAR170070
• License:
  https://creativecommons.org/licenses/by/4.0/
• Rights Information:
  CC BY
• Compliance:
  Submitted
• Main Document Checksum:
  urn:sha-512:f82e6ef6f621c743ebb3e318d2ad87962ce31f9e087eb9007c345ceb3b6757a787957d59a80843beff5a318d3bfc7c33ff2ed03a82954e3698e69fad1791c797
• Download URL:
  https://repository.library.noaa.gov/view/noaa/74075/noaa_74075_DS1.pdf
• File Type:
  [PDF - 1.33 MB ]