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A Day in the Life of a HAB

A Day in the Life of a HAB

woman on boat collecting water sample

After an introduction about what microalgae are, how important they are, and how some species may form Harmful Algal Blooms (HABs), the students will watch a show-and-tell video about “A day in the life of a HAB sample”. This video will demonstrate how we take water samples from a boat and from a pier, what we do to analyze the sample for cell counts and toxins, and how they can find information about red tide themselves. The activity will conclude with a decision tree game where the information provided will be revisited in an interactive manner.

Learning Points

  1. Marine microscopic algae come in all shapes and forms, are the base of the aquatic food web, and responsible for the air we breathe; but that some of them may form blooms that have harmful effects to wildlife and human health.
  2. Karenia brevis, the red tide organism, and its toxin are invisible to the naked eye so that from a water sample we need a microscope to see and count how many cells we can find and specific chemistry methods to detect the toxin.
  3. Students can find a lot of information about red tide and other HABs on their own.


  • Video: A day in the life of a HAB sample
    (found at the top of this page)
  • Decision tree game 
    Some game tips:
    • save the game to your computer and open within Adobe Acrobat or Adobe Reader for the best formatting.
    • do not use your arrow keys to advance the game - click on each choice.

Additional Activities