The taxonomy laboratories – comprising light microscopy, electron microscopy and molecular ecology groups – are essential to statewide harmful algal bloom (HAB) monitoring. To determine when and where HAB species bloom, scientists use microscopy to magnify phytoplankton (microscopic algae) and count HAB species. The information gathered from counting HAB species this way is used to help improve HAB detection by other methods, such as satellite imagery and molecular classification.
Light Microscopy: Scientists use light microscopes to examine water samples during routine and event response monitoring. They identify HAB species by examining the size, shape and other characteristics of each cell. During routine monitoring, scientists examine more than 100 samples weekly, whereas during red tides, they may process up to 300 samples during a single week. All data are entered into the HAB historical database. Scientists report results to managers and partners, who can then determine the appropriate response to events. Each week, sample results for the Florida red tide organism, Karenia brevis, are posted on the Fish and Wildlife Research Institute's (FWRI) Florida Red Tide Current Status Web page.
Electron Microscopy: Some HAB species cannot be identified using standard light microscopes. In these cases, very high magnification is needed to observe cellular or sub-cellular characteristics to identify these organisms. HAB scientists are equipped with two powerful microscopes: a scanning electron microscope and transmission electron microscope, which can magnify organisms from 5,000 to 1 million times. Such technology has allowed scientists to conduct ground-breaking work in identifying and distinguishing toxic algae, including the species responsible for Florida red tides. In fact, they have learned that Florida red tides can be composed of seven different Karenia species. The electron microscopes, which are shared with other FWRI researchers, have also been used to assess the health of other marine organisms, including corals, fish, molluscs, parasites and seagrasses.
People: Karen Henschen | Kate Hubbard | Stephanie Keller Abbe | Karen Steidinger | Maria Célia Villac
Molecular Ecology and Flow Cytometry: Toxic and nontoxic HAB species are sometimes difficult to discriminate even with light and electron microscopy. For these species, scientists at FWRI design and employ genetic tools to identify and/or quantify HABs, including DNA sequencing, phylogenetic analysis, DNA fingerprinting, quantitative polymerase chain reaction (PCR) and in situ hybridization. Genetic approaches are used in tandem with electron microscopy to identify new HAB species that bloom in Florida’s coastal and estuarine waters. These varied molecular tools can also be used to rapidly identify shifts in genetic diversity at the taxonomic scale of interest (e.g., genus, species or population), and across spatial and temporal scales relevant to HAB ecology and bloom dynamics.
In Florida, more than 50 species of microscopic algae are capable of producing toxins. Scientists in the biotoxins laboratory analyze water samples and plant and animal tissues for the presence of these toxins. Current research focuses primarily on brevetoxin (produced by the Florida red tide organism, Karenia brevis) and saxitoxin (produced by the dinoflagellate Pyrodinium bahamense). These toxins can accumulate in filter-feeding bivalves such as clams and oysters and present a serious risk to public health. The biotoxins laboratory at FWRI is the official state laboratory for testing algal toxins in shellfish following harvesting bans caused by red tide. Scientists investigate how these toxins are metabolized in shellfish and their effects on aquatic animals such as manatees, turtles, sea birds and fish. Researchers in the biotoxins laboratory work closely with other groups and agencies to respond to fish kills, marine mammal deaths and other events.
The HAB ecology group studies the relationships between HAB species (including the Florida red tide organism, Karenia brevis), HAB biotoxins and environmental factors to better understand the drivers of HABs in Florida waters. The group contributes to monitoring efforts and conducts diverse research projects, including studies of community dynamics in nearshore waters, nutrient physiology and cell behavior. These studies also generate data that can be used to improve regional models that forecast HAB bloom initiation, duration and termination.
Culture Collection Facility
To study HAB species, researchers often grow, or “culture,” organisms in the laboratory. Most of the species in the HAB culture collection were gathered from water samples collected in Florida. To start a culture, scientists examine a water sample under a light microscope and move single organisms into containers with seawater and nutrients. These single organisms will reproduce if given light and nutrients to grow. Cultures can be maintained for years if fed new nutrients. FWRI’s culture collection contains various dinoflagellate and diatom species, including several different cultures of Karenia brevis, the Florida red tide organism. Cultures are made available for use by FWRI researchers and other scientists in the United States and around the world.
Information Management and Support
The HAB group collects and distributes a huge amount of information. Information management and support staff manage our database, send daily reports to partners and collaborators, fill data requests and update our website with status reports and articles.