Tracking Gray Whale Migration
From California Observation Posts
Data Courtesy of the American Cetacean Society (LA and CI)

Time
1-2 periods; revisit regularly during migration updates.

Standards

Overview
Students record, graph, and analyze migration data that is being collected daily this spring by volunteers at two observation posts in California. By monitoring migration past any single place, scientists can get ideas about a migration's progress along its entire route. Data collected at two sites provides valuable opportunities for comparisons.

Background
Gray whales migrate the farthest of any mammal. Their spring journey from the warm birthing lagoons in Mexico to their frigid arctic feeding grounds is more than 5,000 miles! Journey North follows the migration of these gentle giants and their new babies up the Pacific Coast. Climb to a cliffside post on the the California coast and count migrating whales with the dedicated volunteers of the American Cetacean Society (ACS) Gray Whale Census. You can collect live data from both the Los Angeles and Channel Islands posts.

Preparation
Have students (1) read our downloadable booklet, Gray Whales: The Monumental Migration (or view its slide show format) and (2) explore the Gray Whale Migration Route Map. Decide if you will track the migration past the Los Angeles Observation Post, the Channel Islands Observation Post, or both. Challenge students to come up with a way to graph the migration data, or print
these blank datasheets and graphs:

Use for Tracking: 
Data Sheet 
Graph  
Northbound Migration
Southbound vs. Northbound Migration

Laying the Groundwork
As the season begins, students should have these "big picture" understandings:

  • Gray whales migrate along the Pacific Coast between Mexico to Alaska.
  • Most gray whales are still migrating south when Journey North's season begins in early February!
  • All Gray whales do not travel together or at the same time. In general, groups of whales travel in “pulses.” The pulses generally move up the coast in this order: (1) newly pregnant females, (2) males, juveniles from the previous year and non-pregnant females, (3) cow/calf pairs.
  • Gray whales are hard to see during migration! We can’t follow a single whale or group of whales. This fact is very important to remember when interpreting migration data.
  • Gray whale migration is complex. There are many exceptions to the general notes above about migration patterns.
  • We will watch for key migration events: the turnaround date when northbound whales outnumber southbound whales, and the end of the southbound migration (Los Angeles post only); identifiable pulses; the first northbound calf (with its mom); peak migration dates for the cow/calf pairs; the first whales sighted in the Gulf of Alaska at Kodiak.

Exploration
Sets of data from Los Angeles and Channel Islands will be compiled and provided in each migration update for your convenience. Students will predict and revisit with each migration report as they:

1) Record Migration Data: See details for recording data on the blank datasheet above. A link to this migration data page will be included in each update.

2) Graph the Data: See details for graphing data on the blank graph above. Also see these examples:

  • Northbound Migration (example)
  • Southbound vs. Northbound (Los Angeles only) (example)

3) Analyze the Graphs: Guiding questions will be provided in each update to help students analyze migration patterns and predict key events. Students will routinely revisit their predictions and explanations with each new update.

Making Connections — Journaling and Discussion Questions
Students should maintain a journal through the season to respond to Journey North Challenge Questions and Journaling Questions in updates as well as to reflect on observations, experiences, and data. They can use journals to speculate and put forth opinions, theories, and hypotheses. Suggestions:

• What patterns did you see? How did they compare with your initial predictions?

• In what ways was the migration different than you predicted? Explain what you did not know originally that caused your prediction to be off.

• What did you learn about geography and climate from the migration?

• What did you learn about whale biology and adaptations?

• What unanswered questions do you have about gray whale migration?

Assessment
Use the Making Predictions Using Data rubric as you listen to discussions, review student journals, and see how students revise predictions.

Use assessment suggestions available in Reading and Writing Connections (look for to see which activities are accompanied by these rich lessons). Some will be presented in migration updates throughout the season. They are also listed on our Resources page.

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