Gray Whales and Changing Sea Ice

How far can gray whales go as they journey north to feed and breed in the Bering and Chukchi Seas? Only as far as the melting sea ice allows! You can see this change on daily and monthly ice maps. As you do, try to predict when the gray whales will reach the end of the trail.

Try This!  
  1. Once a week, look at this current sea ice map.
  2. Use a new Journal Page or a large blank map to mark the area the sea ice covers. Be sure to date your maps.
  3. Put an X on the map where the northernmost gray whale has been spotted.
  • How did the ice change over time? Did you notice any patterns?
  • When do you predict the gray whales will reach the Bering and Chukchi Seas?
  • What questions do you have about sea ice and gray whales?

Daily Sea Ice (NOAA)
Click for large map.
Try This!
It can be hard to see patterns of change when you look at something over a short period of time. Here you can see how the ice changed in the past month.
  1. Click on this map to see an animation.
  2. Stop the animation. Click to today's date. Next, click back one frame. You'll be able to see how the ice changed from the beginning to the end of a month.
  • How would you describe the changes?

Sea Ice Animation (NOAA)
(past month)
Click for large map.

Finally, look at the animated map to the right. It shows yearly changes in sea ice concentration by the month.
  • On the basis of these maps, when do you predict the first gray whales will reach their arctic breeding grounds?

Yearly Sea Ice Animation
Click for large map.
Image: Ron Morris

Click for larger images.

Image: NOAA

Image: NSIDC
Journaling or Discussion Questions
How does the environment (in this case, arctic sea ice) change over years and decades? To find out, scientists must collect long-term data. By doing this, they have discovered some alarming changes. Click on each image for a larger version. (Note: The left one includes assumptions about the future.)  
  • What do these findings tell you about changes in sea ice thickness and coverage (extent)?
  • List at least three ways you think these changes — and related ones — could affect gray whales and other marine animals.

Find out what scientists think>>

Other Sea Ice Maps/Resources