Using DNA probes to track harmful
algal blooms in Monterey Bay

Roman Marin III
Monterey Bay Aquarium Research Institute

Friday, July 17, 1998
12:00 noon—Pacific Forum

In 1998 economic losses associated with harmful algal blooms (HABs) have approached roughly 500 million dollars worldwide. The vast majority of these losses stem from the death of farmed finfish (salmon, tuna) that were inundated by massive blooms of single-celled algae in Asia and Europe. In recent years, these types of events have spurred an intense effort to understand the underlying forces driving HAB outbreaks locally and abroad. A primary difficulty in understanding HABs is identifying and enumerating causative species before they become a problem, especially when the suspect toxic phytoplankton are but a minor component of a complex assemblage of microorganisms. One possible means of addressing this problem is through the utilization of molecular probes that enable rapid detection and quantification of specific species.

In the spring of 1998, two harmful algal blooms occurred off the Santa Cruz Municipal Wharf. The first organism to reach toxic levels was Alexandrium tamarense, a dinoflagellate responsible for paralytic shellfish poisoning. The second microalgae to bloom to toxic levels was Pseudo-nitzschia australis. Pseudo-nitzschia australis is a known domoic acid producer that is responsible for amnesic shellfish poisoning, and in the recent bloom was linked to sea lion mortality. Both of these blooms were successfully tracked from onset to collapse in near real time by a novel molecular probe assay currently under development at MBARI. The performance of the assay during these events validated the concept of using this technology to enhance monitoring of a suite of toxic algae that occur in Monterey Bay and in many other regions of the world.

Next: Moving rocks and clogged plumbing: Fluids, sediment transport and tectonics of the Monterey Bay Region