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Making Waves: Episode 39 (November 12, 2009)


Hello and thanks for joining us today. The topic of the day is harmful algal blooms. They're called HABS for short. Heard of them? If you live in a coastal area or near the Great Lakes, chances are you have, but you may know them by their more popular name: 'red tide.' HABs are caused by microscopic algae -- tiny plants in the ocean -- that grow out of control. And as they grow, or bloom, out of control, they produce powerful toxins that kill fish and make shellfish dangerous to eat.We've got three stories today about harmful algal blooms, so stay tuned.

It's November 12th, 2009, and we're going to be talking about all things algae today, and this is Making Waves from NOAA's National Ocean Service.


So let's start off today by talking about where the term 'red tide' comes from. Well, it's from one of the best known HABs in the nation that crops up nearly every summer along Florida's Gulf Coast. This bloom, like many HABs, is caused by microscopic algae -- tiny plants in the ocean -- that grow out of control. And as they grow, or bloom, out of control, they produce powerful toxins that kill fish and make shellfish dangerous to eat.

The toxins can also make the surrounding air hazardous to breathe. As the name suggests, the bloom of algae that turns up in Florida often turns the water a deep red color.

Scientists prefer the term harmful algal bloom, or HAB, because the toxic blooms of algae that occur in waters around the world come in many forms. Not all blooms are red. They come in a variety of colors...some have no color at all. And some algal blooms are harmful even though they don't produce toxins, simply because the algae grow in such vast quantities that, when they die, they suck all of the oxygen out of the water as they decompose.

So there are many varieties of harmful algal blooms. They come in many shapes and sizes, and they are universally a big problem. They threaten marine ecosystems, they're bad for human health, and they cost local and regional economies millions of dollars every year through fishery closures, and recreation and tourism losses because vast swaths of water have to be closed off until the threat passes.

These blooms happen in almost every U.S. coastal state and in the Great Lakes and they seem to be on the rise. But why do these harmful blooms of algae occur?


Well, a new study sheds light on this. It was carried out by NOAA and NOAA-funded university scientists, and it takes a close look at the close cooperative interactions between bacteria and marine micro-algae. This interaction, it turns out, promotes the growth of harmful algal blooms.

That the algae that forms harmful blooms and some types of bacteria are linked is not news. Scientists have known this for a long time. The mystery is why? Exactly why do these toxic blooms form, and what role does the bacteria play in this cycle? That's where this new study comes in.

The researchers found that certain species of bacteria form a mutually beneficial relationship with the algae that promotes the growth of each. The bacteria release a chemical which helps the algae absorb iron, and this is a critical nutrient for photosynthesis. The algae, in turn, release organic compounds to support the growth of the bacteria.

The new research could have huge implications. Better understanding this interaction could help researchers create more accurate models of how blooms form, but it could also help with better forecasting: predicting when and where blooms are likely to form. Added to this, the research could point the way to new strategies to prevent these harmful outbreaks. If scientists can now find a way to inhibit the bacteria from growing, then that could lead to ways to better control the problem. That's something that would help coastal communities around the world.

The study also offers new insight for climate change models. It turns out that a gas produced by the bloom-forming algae, called dimethylsulfide, plays a critical role in the process of cloud formation and the ability of clouds to reflect sunlight back into space. What does this have to do with climate change? How much light is reflected off of clouds and back into space influences solar heating of the Earth, and that affects global climate. That study, again, appears in the Proceedings of the National Academy of Sciences. It was funded by NOAA's National Centers for Coastal and Ocean Sciences.


Well, as I mentioned a few moments ago, forecasting is a big deal for HABs. Forecasts that tell us current and future locations of blooms, as well as intensity, are critical to alert scientists and managers to possible threats -- and helps to better manage or lessen the impact of the toxic blooms. When most people think of red tides, they probably think of coastal states. But the Great Lakes are also facing growing problems with toxic algal blooms.

One type of harmful bloom that is a particular problem in the Great Lakes is caused by a blue green algae Microcystis. These blooms are blooms are increasing in frequency and duration in the Great Lakes, in part due to the invasive zebra mussel that filters Great Lakes water and removes other algae competitors. Mycrocystis blooms can produce a toxin that can cause skin rashes, liver damage, fish kills, and taste and odor issues in drinking water.

Until now, there hasn't been a system in place to help predict HABS in the Great Lakes. Now there is, with the kick-off last month of a new a new experimental HAB forecast system in Lake Erie.

Here's how it works. When a harmful bloom in Lake Erie is detected by the experimental system, scientists issue a forecast bulletin to nearby scientists and community managers. The bulletin depicts the HABs' current location and future movement, as well as categorizes its intensity on a weekly basis.

With the new forecast, scientists now have a much better idea of when and where blooms are predicted to occur, and this critical information can be shared with on-the-ground local managers to reduce human health threats.

The experimental forecast incorporates data from a number of ocean-observing systems, including commercial and government satellite imagery obtained by NOAA's National Ocean Service, coastal forecast modeling and field data by NOAA Great Lakes Environmental Research Laboratory scientists, and reports received from resource managers in the field. The information is then put together and interpreted to help figure out the current and future location and intensity of Microcystis blooms.

The experimental forecast created for Lake Erie and the state of Ohio was based on the detection system that NOAA's National Ocean Service designed for Florida's Gulf Coast in 2004. This is only the beginning. This system will serve as a model for other areas of the U.S. impacted by HABs. The new system was jointly funded by NOAA's Oceans and Human Health Initiative and the Centers for Disease Control and Prevention's National Center for Environmental Health.


In our final story today, we're going to talk about a special group of people who volunteer their time to help NOAA find and track harmful algal blooms around the country. These volunteers make up NOAA's Phytoplankton Monitoring Network. The thing about harmful algal blooms is that they come in a wide variety of shapes and sizes. And the scientific names of the more than 50 types of diatoms and dinoflagelletes tracked by NOAA's Phytoplankton Monitoring Network are hard to pronounce. They can be equally hard to identify in the wild.

Training volunteers is a challenge. No one knows this better than Steve Morton, research oceanographer and program lead for the Network, part of the National Centers for Coastal Ocean Science (NCCOS). Morton manages the nationwide group of 'citizen scientists' who help monitor harmful algal bloom and phytoplankton around the country.

While Morton and his NCCOS colleagues host a variety of instructional tools on the PMN Web site to assist people who want to help out with the monitoring effort, wouldn't it be nice to have photos of these tiny creatures, pronunciations of their names, and other reference tools on a handheld device? Monitoring phytoplankton, after all, is something people do in the field, far from an internet connection and a computer.

Well that was the inspiration of one volunteer to develop an iPhone application.

His name is Shawn Gano, and he's a volunteer with the Armand Bayou Nature Center in Pasadena, Texas.

Well, since he had experience with computer applications, he approached Morton with the idea in July 2009. Months later, the first-ever phytoplankton identification application was launched for the iPhone. It's called Phyto.

Since Shawn had experience with computer applications, he approached Morton to see if they could collaborate to produce an mobile application to help other volunteers out.

This led to a new application now available to download for free for the iPhone or iPod Touch. The new "app" includes images from an NCCOS gallery of common phytoplankton and recordings of a staff scientist's pronunciation of each species' name. The application also contains a flash card game to improve volunteers' identification skills. Morton said they are now going to work on producing other versions of this iPhone application for the other regions covered by the Phytoplankton Monitoring Network.

The Phytoplankton Monitoring Network was established as an outreach program for monitoring marine phytoplankton and harmful algal blooms (HABs). By linking the general public to laboratory scientists, the PMN helps to build a more informed public while providing useful data to scientists.

The PMN began with three volunteer groups in Charleston, South Carolina, and has since expanded throughout the coastal U.S. to now include more than 200 volunteers actively sampling over 140 sites in 17 states and the U.S. Virgin Islands.

The data Network volunteers collect provides an important look into species composition and distribution in coastal waters -- data which can help researchers identify areas to isolate for further investigation.


That's all for this week's episode. If you want to learn more about harmful algal blooms and the ongoing NOAA research to fight this problem, start you journey at ....... And don't forget to surf over to for the latest news and information about our oceans, coasts, and Great Lakes.

If you have any questions about this week's podcast, about the National Ocean Service, or about our ocean, send us send us an email at

Now let's bring in the ocean....

This is Making Waves from NOAA's National Ocean Service.