How marine mammals stay warm
Wear a “blubber glove” and plunge your hand into an ice water bath to investigate the insulative properties of blubber.
Please find a printable PDF of this activity here.
- Blubber is important for most marine mammals, such as whales and seals. The thick layer of fat provides insulation from cold ocean temperatures.
- Blubber is also important because it stores energy that can be broken down to provide the animal energy when food is unavailable.
- Weddell seals live in Antarctica and can have more than 2 inches of blubber. Considering their massive weight of 400-600 kg (880-1320 lbs), that could be up to 240 kg (530 lbs) of pure blubber.
- Bowhead whales live in Arctic waters and can have 43-50 cm (17-20 inches) of blubber, thicker than any other whale's blubber layer.
- 3 gallon or quart size zippered plastic bags
- 1 large container of lard or shortening
- Heavy tape
- 2 large containers of ice or ice water
- Optional: Heavy rubber kitchen glove
- Scoop fat into two of the zippered plastic bags. Spread the fat inside the bag so that it fills the bag and is about 1 inch thick. Seal the bags.
- Lay one bag on top of the other and tape three of the sides together making a “mitten."
- Slide the mitten into the third bag with the open side of the mitten facing out of the third bag.
- Put the mitten into one of the containers of ice, or ice water.
- Put one hand into the mitten and put your bare hand into the second container of ice.
- Optional: Use a heavy rubber kitchen glove can for the bare hand. If a lot of people are doing the activity this will help keep the demonstration area dry.
- Use a thermometer to measure the temperatures over time, with and without the mitten, and graph the results.
- Predict results and test mittens with different thicknesses of fat.
- Predict results and test mittens with different materials for insulators.
- Investigate the thickness of different marine mammals blubber and make models showing the actual thicknesses.