Here is table that shows the approximate sizes and weights of whales found in the southern hemisphere, and the best estimates of their original and present abundance.

Source of population estimates:
* International Whaling Commission whale population estimates

Humpback whale. Photo: Nick Gales

• As with the seals activities (and preferably combined with them), have students weigh themselves and work out how many individuals are needed to equal the weight of each whale. The students could also measure their height and compare the length of children to each type of whale.
  (Blue whales may be the largest animals that ever lived, although it's now thought that some sauropods (herbivorous dinosaurs) may have been larger. The biggest blue whale ever weighed was nearly 200 tonnes and over 30 m in length!)
• Students can create life-size scale drawings of whales, either with chalk on the playground, or in the school hall or hallways (if you can get butcher’s paper large enough).

• Ask students to use the whale table to draw a graph that shows both the original estimated numbers, and current estimated numbers, of different whale species.

• Minke whale.

  What has been the decline in each species - in numbers, and in biomass?
  
  The massive reduction in the stock of whales as a result of commercial whaling activities is the single largest human impact to the Southern Ocean ecosystem. Ask the students to suggest reasons why the population of minke whales has increased. (Minke whales have only been commercially hunted since the 1970s, after the stocks of blue and fin whales were exhausted.)
• Japan kills about 300 to 600 minke whales a year in the Southern Ocean for scientific research. As the minke whale populations is so large, should sustainable whaling in Antarctica be allowed? If not, why not? Are whales a special species that need to be specially protected? Is it more profitable to take tourists to watch whales, or to hunt them and sell their meat?
• Ask students to research the history of whalers and whaling. If whalers operated out of your local port in the 19th century, ask students to research the local history of whaling.

• Whale. Photo: Nick Gales

  Ask students to discuss why it is difficult to make accurate counts of whales numbers.
  (Only a small percentage of whales will be visible on the surface as the vessel passes. Seeing whales is very dependent on sea and light conditions. As whales are now so rare and widely dispersed, extrapolations must be made from the sightings of only a tiny fraction of the populations.)

Further information:
Information on blue, humpback, minke, sei and southern right whales and orcas is the Australian Antarctic Division's whale fact files.

See Environment Australia's whale website.

Don't miss the ABC's whale dreams
The American Cetacean Society's website features
a teachers' guide to introducing and using whales, dolphins, & porpoises in the classroom and
ACS cetacean fact packs.

Have a read of the World Wide Fund For Nature's May 2007 article

Japanese scientific whaling: irresponsible science, irresponsible whaling [PDF].


You can read about the origins and character of 'aboriginal subsistence' whaling: a global review.


The article hunting tradition: treaties, law, and subsistence killing [.doc] gives a good overview of the traditions practiced by North American Indians.


Finally, try whales: a thematic web unit for learning activities across an integrated curriculum.