Robotic Imaging System Warns of Gulf Toxic Algal Bloom
April 4, 2008
DURHAM, N.H. -- A CICEET-sponsored, early warning system for harmful algal blooms passed its first test recently when it alerted coastal managers to an impending bloom of toxic algae on the Texas coast, and prompted the closing of Aransas, Corpus Christi, and Copano bays to shellfish harvesting.
The prototype robotic technology—the Imaging FlowCytobot—is being developed through a grant from the Cooperative Institute for Coastal and Estuarine Environmental Technology (CICEET), a partnership of NOAA’s Office of Coastal Resource Management and the University of New Hampshire.
“NOAA has been forecasting harmful algal blooms in the eastern Gulf of Mexico using a combination of satellite imagery and field sampling for a few years now,” says Dwight Trueblood, CICEET’s NOAA co-director. “However, there is a real need to ground truth blooms in real-time so that managers can warn the public in a timely manner, while minimizing the impact on local economies that depend on open public beaches and safe seafood.”
The Imaging FlowCybot captures cell images from a continuous stream of seawater that flows through the system, and relays these images by Internet to the lab, where they are automatically classified into taxonomic groups.
“What sets this technology apart is the combination of continuous monitoring with a software-based classification system that can handle millions of images,” says Robert Olson, a scientist from Woods Hole Oceanographic Institution and lead investigator on the project. “It provides a searchable, visual archive that allows us to monitor and analyze phytoplankton population dynamics that precede a bloom.”
The Imaging FlowCytobot is being demonstrated by scientists from Texas A&M University at the University of Texas Marine Science Institute Pier, part of NOAA’s Mission-Aransas National Estuarine Research Reserve. In mid-February, researchers observed elevated counts of Dinophysis acuminata, an alga that produces okadaic acid, which can accumulate in shellfish and can cause diarrhetic shellfish poisoning (DSP).
Based on this early warning, the Texas Department of State Health Services evaluated water and oyster samples from the monitoring site, and issued a recall of Texas oysters, clams, and mussels, and the Aransas, Corpus Christi, and Copano bays were closed for shellfish harvesting. State officials are not aware of any illnesses resulting from this algae bloom. Although Dinophysis species occur throughout the Gulf of Mexico, the Texas A&M researchers say they have never seen D. acuminata at such concentrated bloom levels in the Gulf.
“Originally, our goal was to test this technology as an early warning system for Karenia Brevis, the dinoflagellate most commonly responsible for red tide in the Gulf of Mexico,” says Lisa Campbell, the Texas A&M professor on the project. “Because we are looking at stored images, we can quantify many different cell types, not just the expected bloom species. This flexibility allows us to detect increasing populations before human illness or fish kills are reported.”
Harmful algal blooms occur in the waters of almost every U.S. coastal state, caused by numerous different species. Their direct economic impacts in the United States are estimated to average $75 million annually, including public health costs, commercial fishing closures, recreation and tourism losses, and in management and monitoring costs.
This prototype robotic technology˜the Imaging FlowCytobot˜combines continuous monitoring with a software-based classification system that can handle millions of images, and quantify many different cell types, not just the expected bloom species. This flexibility allows for the detection of increasing populations before human illness or fish kills are reported.