A research paper published this week reveals that large die-offs of algae locally magnify ocean acidification. As the cells die and sinks to the bottom, the bacteria population that feeds on them swells in response, consuming more oxygen and releasing more carbon dioxide (CO2). The CO2 reacts in seawater to form acidic compounds that lower [...]
When tiny aquatic organisms reproduce in large amounts, algal blooms occur that take over portions of open water up to hundreds of miles in area. And when these oceanic plankton happen to be the toxic kind, they can be deadly to other living things crossing their path. One of the most poisonous and abundant of [...]
A University of Connecticut researcher and his team have discovered that a species of tiny aquatic organism prominent in harmful algal blooms sometimes called “red tide” is even deadlier than first thought, with potential consequences for entire marine food chains. Professor Hans Dam and his research group in the school’s Department of Marine Sciences have [...]
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. [...]