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New Technology Helps Warn Shellfish and Fish Farmers of Harmful Algal Blooms


The Environmental Sample Processor is currently (June 2012) deployed at Friday Harbor Lab on San Juan Island in northern Puget Sound in Washington State. The ESP detects DNA of Harmful Algal Species in real time.

Heterosigma akashiwo is a microscopic swimming marine algae 
that forms harmful algal blooms when certain environmental conditions are met. (Credit: Gabriela Hannach, King County DNRP)

August 8, 2012

Puget Sound is one of the most valuable locations in the country for shellfish and fish farms; the shellfish industry injects nearly $100 million a year into the region’s economy. Unfortunately, this hot commodity is particularly vulnerable to toxin-producing harmful algal blooms, which can contaminate or even kill farm-raised shellfish and fish.

Every year, harmful algal blooms cause approximately $82 million in damages to commercial fisheries and aquaculture, public health, and the recreation and tourism industries around the country, yet we don’t have reliable ways to forecast and predict when they will occur. For aquaculture businesses, reliable predictions of bloom events would allow them to harvest their products when it is safe and minimize potential consumer and economic risks.

Advanced Technology Deployed

This summer, NOAA scientists at the Northwest Fisheries Science Center in Seattle tested a novel new instrument – the Environmental Sample Processor, or ESP – for its ability to detect the microscopic species that cause harmful algal blooms and provide warning of an impending outbreak.

Scientists stationed the ESP at Friday Harbor in the San Juan Islands of Washington State in June and July. Each morning, the ESP collected 1 liter of water and tested for four different species of harmful algae using DNA probe technology. The ESP conducts the DNA processing and sends an email with the results to the scientists back at their offices.

This ESP deployment was the first-ever in the Pacific Northwest and targeted one of the primary fish-killing harmful algal species, Heterosigma akashiwo. Scientists also learned that Heterosigma is consistently present in the water column at low levels during this time of year, but only blooms when conditions are right – an important aspect of the ecology of this species that scientists did not previously know.

The ESP in fact provided early warning of a large bloom that had the potential to kill fish. The information was rapidly disseminated to businesses and triggered increased site surveillance at fish farms throughout Puget Sound and British Columbia. In the event of a higher risk bloom forecast, shellfish growers may harvest their product early to avoid contamination with HAB toxins, fish farmers may ramp up site surveillance and prepare mitigation strategies, and salmon hatchery operators may delay the release of juveniles.

Detecting HABs with ESP

A network of ESPs strategically placed in hot spots throughout Puget Sound would provide near real-time knowledge of what species are present in the water and at what densities. When combined with weather forecasts to determine when conditions are right for blooms to develop, the ESP would be a critical component of an advanced early warning system for harmful algal blooms. This information could save aquaculture and other businesses – and the public – millions of dollars annually.


This work is the result of a partnership among NOAA’s NWFSC; the Monterey Bay Aquarium Research Institute; Spyglass, Inc.; and the University of Washington. Funding has been provided by NOAA’s Oceans and Human Health Initiative, the Integrated Ocean Observing Systems “Sensors for Ecosystems” Program, and the ECOHAB Program.