Fish farmers now have a space-age early warning system to advise them of approaching blooms of dangerous algae that could kill fish held in sea cages and prevent the deaths of people who eat infected shellfish.
Fish farmers in Chile, one of the world's major producers of farmed salmon, can now tap in to an early warning system that uses satellite data to show the movement of potential Harmful Algal Blooms or HABs.
HABs occur when certain species of algae reproduce rapidly and produce toxins and deplete oxygen levels that can cause serious physical or biochemical damage to fish and other marine life.
Using the new satellite system, fish farmers can access live data via the Internet using a system created by Hatfield Consultants Ltd under the European Space Agency (ESA) funded Chilean Aquaculture Project (CAP).
The Earth Observation (EO) data produced by the system shows imagery of potential HABs viewed from space and makes predictions of where they are likely to spread.
The ESA explained that the technology works using the pigment produced by the algae:
"Just like plants on land, algae employ green-pigmented chlorophyll for photosynthesis - the process of turning sunlight into chemical energy. The chlorophyll collectively tints the colour of the surrounding water, providing a means of detecting these tiny organisms from space with dedicated 'ocean colour' sensors onboard satellites.
"The CAP project utilises a combination of near real-time EO data, such as chlorophyll-a pigment concentration, secchi transparency, suspended matter and sea surface temperature, derived from the MERIS instrument onboard ESA's Envisat satellite and the MODIS instrument onboard NASA's Aqua satellite and in situ water monitoring to monitor the Southern Ocean off the coast of Chile."
Harmful Algal Blooms occur naturally around the world, but the ESA says that they have been seen more regularly during the past 30 years and have caused millions of pounds worth of damage to southern Chile's 360 fish farms.
Caged salmon are at risk because they cannot escape the oxygen-depleted water the blooms produce, while farmed shellfish, such as mussels, accumulate toxins from the algae in their tissues, which means that they are then unsafe for human consumption.
Eating shellfish that have filter-fed on the harmful algae during a HAB outbreak in 2004 caused 73 cases of paralytic shellfish poisoning in people who ate the mussels, as well as the death of two people.
And, poisonings are on the rise. In 2004 there were 1500 cases, while in 2005 there were 10,000 including one death.