University and NOAA investigators have found seed-like cysts of the toxic alga Alexandrium at all depths in a sediment core taken from Sequim Bay in Puget Sound. The depths in which they found the seeds indicate Alexandrium dates back to the late 1800’s. Correlations between cyst abundance, sea surface temperature, air temperature, and, for a shorter [...]
In a new paper, researchers funded by the National Centers for Coastal Ocean Science discovered that the New England red tide species called Alexandrium releases a variety of compounds to kill its predators and lengthen bloom duration. In this case, the substance they use for defense is not the potent neurotoxin that accumulates in shellfish [...]
A recent study funded by the National Centers for Coastal Ocean Science investigated the role of specific phosphorus and nitrogen compounds in determining the amount and composition of Paralytic Shellfish Poisoning-causing toxins in cultures of two harmful algal bloom (HAB)-forming dinoflagellates from Hong Kong, Alexandrium catenella and Alexandrium tamarense. Growth and toxicity of even these [...]
The likelihood of frequent exposure to saxitoxins in the New England region, specifically in Maine, may be a serious long-term health threat to shortnose sturgeon (Acipenser brevirostrum). NCCOS scientists have now confirmed the presence of saxitoxins in this endangered species and provided evidence of food web transfer of these toxins produced by the harmful algae [...]
A NCCOS Ecology and Oceanography of Harmful Algal Blooms (ECOHAB)-funded study at the University of Washington and the NOAA National Marine Fisheries Service laboratory in Seattle has developed a unique and convenient way to detect very low levels of exposure to the harmful algal toxin domoic acid in laboratory zebrafish and in wild California Sea lions. [...]
NOAA scientists and their colleagues have discovered a biological marker in the blood of laboratory zebrafish and marine mammals that shows when they have been repeatedly exposed to low levels of domoic acid, which is potentially toxic at high levels. While little is known about how low-level exposure to domoic acid affects marine animals or [...]
A project to model favorable habitat areas for the dinoflagellate Alexandrium catenella is underway in Washington’s Puget Sound. Sediment from nearly 100 sites will be sampled during two cruises in January and February and the cyst abundance mapped. Alexandrium produces potent neurotoxins that accumulate in shellfish and cause severe illness or death in people who eat [...]
Dr. Barbara Hickey of the University of Washington recently presented the current status of their harmful algal bloom (HAB) modeling efforts to state, tribal, and federal agency partners with the Washington State Olympic Region Harmful Algal Bloom (ORHAB) Program. HAB managers learned of recent modeling advances that may benefit regional efforts to predict and mitigate [...]