Student Activity

Overview
 Harmful Algal Blooms (HABs) have become a national concern because of their adverse affects on the health of people and marine organisms, as well as the "health" of local and regional economies. The increased interest in HABs is the result of a public awareness of the adverse affects these blooms have on marine resources. Some of thes effects include the beachings and deaths of marine mammals, birds, and sea turtles. In addition, scientists have determined that there are more toxic algal species, algal toxins, affected fisheries resources, food-web disruption, and economic losses from harmful algal blooms than ever before (Anderson et al. 1993). Interestingly, they are not a new phenomena. There are written references of these toxic species dating back to Biblical times. In fact, dinoflagellates and cyanobacteria have been found in the fossil record.

Understanding the ecology and oceanography of these species, and how they affect other organisms, including people, continues to be a challenge for researchers. What are the causes and effects of HABs? Where do these toxins typically occur? How can we track the presence of these harmful toxins to prevent health, economic, and marine resource losses? Let's find out!

Goals
 You will:

  • Learn how to read color satellite images
  • Interpret satellite images to better understand HAB events,
  • Use satellite and GIS maps to analyze the relationship of manatee deaths to HABs

Explanation of Questions
This lesson is designed to help you create a hypothesis, research it, and make a conclusion about HAB's. You can do this by using the NOAA/NESDIS website to help you find data for research. Your teacher will help to guide you in the appropriate direction by helping your group create a valid hypothesis, discover the best methods to research your hypothesis, and show you ways to find appropriate data to support your hypothesis. This lesson will give you a few examples of questions and supporting data so that you can come up with questions and supporting data of your own.

Questions
All external links open in a new window.

  1. Look at the two images found on the following site:

    2. http://cics.umd.edu/~chrisb/gbreve.html

    The first image is a coastal-zone, scanner image of ocean color off the west coast of Florida. The second image is a composite showing red regions where algal blooms (k. brevis) are present. Do you notice any interesting coastal characteristics that may be associated with the presence of k. brevis in the area?

  2. Read the information about the experimental imagery products that NOAA/NESDIS is currently working on to detect HABs:

    3. http://cics.umd.edu/~chrisb/gbrv_www.html

    The two images shown on this web page show images from the winter and summer. The red shows evidence of k. brevis. Are there any correlations between the location of k. brevis in the Florida gulf coast in the winter versus the summer?

  3. Now let us examine an entire year of images. First examine the 2002 images of locations of k. brevis in the Gulf of Mexico:

    4. http://cics.umd.edu/~chrisb/gbrv_www_2002.html

    Where does the concentration of k. brevis appear to be located through the most recent months? Does the location of the k. brevis bloom appear to shift at all? Can you hypothesize why a shift may or may not occur?

  4. Now let’s examine other archived years of images. Click on the following website and scroll to the bottom of the page. You will see archived years ranging from 1997 to 2001.

    5. http://cics.umd.edu/~chrisb/gbrv_www_2002.html

    Examine the images from each year and note the season and location of k. brevis. Which year appears to have an unusually low presence of HABs? In what three locations do you consistently find the presence of HABs? Look at a world atlas or state map of the United States. Are there any geographic features that these three locations have in common that might warrant the presence of HABs?

  5. Go to the following website: http://www.csc.noaa.gov/crs/habf/index.html. After reading about the NOAA Harmful Algal Bloom Project,visit the HAB Observing System (HABSOS). Look at the current red tide conditions and note their locations. Now click on Harmful Algal Blooms Observing System - Near Real Time Map Viewer and explore the HAB interactive map.

    6. Where are HABs currently present? Turn on and off the various SST images. Is there any correlation between SST and the presence of HABs?

  6. Go to the following website and scroll down to see the archived data of SST maps. http://imars.usf.edu/cgi-bin/db?site=gulf&index=1&type=st&mode=daily. Pick a month or a year of SST maps found on this site and compare these to the presence of HABs found at this site: http://cics.umd.edu/~chrisb/gbrv_www_2002.html

  7. Explore the information from the following site: http://www.whoi.edu/redtide/.

    What are some of the harmful affects of HABs on humans and other marine organisms?

  8. Look at the expansion of HABs pre- and post-1972:

    http://www.whoi.edu/redtide/page.do?pid=18116

    What coastal regions appear to have a dramatic increase of HAB outbreaks post-1972?
    What do you think causes this increase?
    What HAB outbreak is most common along the coasts?

Additional Questions to think about

1. Are there significant links between land-based activities and HABs?

2. Are there strategies to control, mitigate, and ultimately eliminate the outbreaks and health impacts of harmful algal blooms?

3. What effects do HABs have on higher trophic levels?

4. Should we be concerned about what types of seafood we eat and where they come from?

Continue to the HAB Investigation