Illustration of the Week: Observation of a Fr securely placed buoy
In the waters off the coast of Del Mar, a mooring is playing a crucial role in advancing our understanding of oceanographic and ecological dynamics. Operated by the Ocean Time Series Group, this mooring has been in operation since 2006 and is the site of recent developments in the Imaging FlowCytobot (IFCB) and acoustic "fish tollgates".
Imaging FlowCytobot (IFCB) Developments
The IFCB, a collaboration between the Barton Lab and Heidi Sosik from Woods Hole Oceanographic Institution, has seen significant advancements. Improved machine learning and AI capabilities have enhanced the IFCB's ability to automatically classify phytoplankton species with higher accuracy, enabling near-real-time assessment of algal bloom composition and dynamics.
The IFCB at Del Mar is also being used in conjunction with physical and chemical sensors, allowing researchers to correlate plankton community changes with environmental conditions more precisely. New communication protocols facilitate faster transmission of high-volume imaging data, enabling more timely data analysis and decision-making. Engineering improvements have increased the instrument’s durability and deployment duration, allowing continuous year-round monitoring even in harsh ocean conditions.
Acoustic "Fish Tollgates" Developments
Acoustic sensors, or "fish tollgates", equipped with multibeam and split-beam echosounders, are now using improved signal processing algorithms to better discriminate fish species, school sizes, and behaviour patterns, reducing false positives. These tollgates are also being integrated with IFCB and other biological sensor outputs to link plankton availability with fish movement and abundance, enhancing ecosystem-level analysis.
Advances in onboard processing enable near-real-time assessment of fish passage and biomass at the mooring, supporting fisheries management and conservation efforts. The acoustic tollgates now support adaptive sampling strategies, focusing effort on detected fish schools to optimise data collection efficiency and resolution.
Impact and Applications
These developments at the Del Mar mooring are helping scientists track plankton bloom dynamics and fish response with fine temporal and spatial resolution. They are also aiding in understanding trophic interactions and ecosystem changes linked to climate variability. The critical data collected is providing support for sustainable fisheries and marine ecosystem management.
The mooring is also a vital part of the Observational Techniques in Oceanography: At-Sea Practicum, where students learn observational oceanography skills. It is also used for testing new moored sensor technologies, such as the Imaging Flow Cytobot and acoustic "fish tollgates".
The mooring measures ocean temperature, currents, oxygen concentration, chlorophyll abundance, pH, and acoustic backscatter from fish. The data collected is transmitted in real time, providing valuable insights into the ocean's health and dynamics.
Photographs of the mooring, taken by Cameron Wilkinson, are featured in the Related Image Gallery: Photo of the Week 2018. Ethan Morris, a marine mechanic, works for Uwe Send's Ocean Time Series Group, contributing to the maintenance and operation of the mooring. The mooring's collaborations extend to David Demer from NOAA's Southwest Fisheries Science Center.
For those interested in the latest specific publications or project reports detailing these upgrades, feel free to ask!
Science and technology are integral components in the advancements at the Del Mar mooring. The Imaging FlowCytobot (IFCB) has seen improvements in machine learning and AI capabilities, enabling higher accuracy in automatically classifying phytoplankton species, while acoustic sensors, or "fish tollgates", now use better signal processing algorithms to discriminate fish species and behaviors (science, technology). These advancements are crucial for understanding trophic interactions and ecosystem changes linked to climate variability, supporting sustainable fisheries and marine ecosystem management (science, technology, environment).
