Harmful Algal Blooms (HABs)
Algae, single celled plant-like marine organisms, are critical to life on Earth. Marine algae range from microscopic single celled organisms (phytoplankton) to larger mulitcellular seaweeds like kelp. As photosynthesizers, harvesting energy from sun to produce their own food, algae are the base in many marine food webs. Oxygen is another product of photosynthesis, and single-cell algae (phytoplankton) living in the ocean are responsible for half of the oxygen produced on Earth.
Algae as a group are immensely important to the functioning of our planet, but there are a few dozen species of algae which can cause serious problems. These species become noticeable during periodic events known as "harmful algal blooms" (HABs). Algae can grow at rapid rates (bloom) and overgrow other species, alter habitats, or deplete oxygen (though algae produce oxygen while they are alive, the decomposition of large amounts of dead algae can deplete oxygen). Some algae are capable of producing powerful toxins that are harmful or deadly to other species. Impacts of HABs include fish kills, injuries to marine invertebrates and marine mammals, and even human illness or death.
The causes of HABs are not fully understood. In some cases, environmental changes such as alteration in water flow or water temperature have been observed to coincide with HABs. In many aquatic ecosystems, nutrients (such as nitrates and phosphates) are scarce and this limits algae growth. When additional nutrients are available through runoff from land, pollution or changes in water circulation, this natural control on algal growth is removed, often resulting in rapid growth of aquatic algae. Scientists suspect that increases in nutrients may also play a role in some HAB events. HABs are a threat to living resources, fishing, tourism, and human health. The number and intensity of HAB events appear to be increasing.
Is Shellfish Safe?
Washington Shellfish Safety Information
Oregon Shellfish Closures
Timely information on harmful algal blooms in the PNW.
Detecting Harmful Algal Blooms in the Pacific Northwest
NANOOS Awarded Funds to Study 2015 West Coast Bloom
NOAA Funds HAB Forecasting System
Phytoplankton Bloom in Hood Canal 2016
NANOOS Ocean Technology Transfer Grant for 2014-2017
Overview of 2015 HAB Event
How are HABs Monitored?
Related NANOOS Products
The NANOOS Visualization System (NVS) provides easy access to forecast and observation data across a wide range of assets such as buoys, shore and land stations, high-frequency radar, and satellites.
Water Quality for Shellfish Growers
Access a wide range of water quality data tailored to the shellfish growing community.
Samish Bay Biosensor
The NWFSC Environmental Sample Processor (ESP) is an advanced biosensor for micro-organisms, including those responsible for harmful algal blooms.
National Observing System Partners
Integrated Ocean Observing System IOOS