Bloom Detectives: Using the Imaging FlowCytobot to identify Harmful Algal Blooms

Overview

How do we know what kind of phytoplankton are in the water? The Imaging FlowCytobot (IFCB) is a robot that scientists use to image phytoplankton in the water. One IFCB can take up to 30,000 pictures per hour! The IFCB can be used in the field to detect plankton blooms in real time. In this activity, students will practice identifying phytoplankton in IFCB datasets and will compare summer and fall communities from several locations in the Alaskan Arctic.

Objectives

• Students will use a guide to identify different kinds of plankton present in the data.
• Students will compare the plankton present in summer and fall to determine how changing conditions alter the composition and diversity of the plankton community
• Students will identify harmful algal species and determine what time of year blooms are more likely to occur in the study region.

Lesson Preparation

This lesson will be most effective if students have some background knowledge on photosynthesis, plankton, and the role of plankton in the ocean.

• Provide copies of the IFCB data for each student or group. One possibility is to make each student or group responsible for one location at one time of year, and then they can compare results with student(s) or group(s) who analyzed data from the same location at a different time of year. Another possibility is to give each student or group both sets of data from a given location so that they can compare on their own.

• Provide each student or group with a calculator to calculate the HAB cells per liter.

• One copy of the questions for each student.

• One copy of the Kachemak Bay National Estuarine Research Reserve phytoplankton guide for each student or group.

Procedure

Engage

Introduce the topic of harmful algal blooms (HABs), either with local headlines or headlines from the Alaskan Arctic such as these, which refer to the summer IFCB data analyzed in this activity:

• Authorities warn subsistence users about potentially harmful algal blooms (Article 1)

• Researchers find high concentrations of harmful algae in regional waters (Article 2)

• Researchers find even higher algal levels in regional waters (Article 3)

** These articles are also accessible in PDF form in Attachments.

Ask students how they think scientists could detect a HAB event.

Context

Show some examples of IFCB images and explain how the IFCB works, and show students the IFCB images of HAB species (see accompanying slide deck).

For more context, read the blog post Robots

Data analysis

Introduce students to the three datasets (Bering Sea North, Bering Strait, and Chukchi Shelf).

Demonstrate how to use the phytoplankton guide (it helps to emphasize to the students that they should look at the shape of the plankton in their data and see if they can find a matching shape in the guide) Students should use the guide to identify the plankton species in their data. Students can also record how many of each species are present.

Students record the species they find, along with the quantity of each species, on their data table. Students only need to identify and record the 3-5 most abundant species in each dataset; there is no need to try to identify all the species in each dataset.

Discussion

Students will answer the analysis questions. If they only analyzed one dataset, they can share and compare data with other groups that had the same location as them but a different time of year. Students can also compare results with groups or students that analyzed data from other locations.

• In what season did HABs occur?

• Why do you think the HABs happened in the summer? (factors to consider include amount of sunlight and water temperature).

• How were the plankton communities in the summer and fall similar? How were they different?

• How did the plankton communities vary across the different locations?

Extension

• Saxitoxin game (Upcoming Lesson Plan)
• HAB identification activity
• Collect and identify plankton samples from local waters

Transferability

This activity could be done in a virtual setting by providing students with digital copies of the data, field guide, and worksheet.

This activity could transfer to an informal setting, where it could be paired with collecting and identifying local plankton samples.

Resources

Middleton, Jane and Bursch, Katie. Marine Phytoplankton of Kachemak Bay. Kachemak Bay Research Reserve, 2015. https://accscatalog.uaa.alaska.edu/sites/default/files/Phytoplankton%20Guide_May_11_2015_sm.pdf

Assessment

Completed lab worksheet, class participation

Author/Credits

Rebecca Siegel, PolarTREC teacher 2022
Brevig Mission School
Brevig Mission, AK
rebecassiegel [at] gmail.com

Evie Fachon
PhD Candidate, MIT-WHOI Joint Program
efachon [at] whoi.edu