2009 SMILE Winter Teacher Workshop High School Club Activities WhaleWorks

WhaleWorks: Answer Booklet

STATION A: Good Vibrations

At this station, you will be using tuning forks to experiment how sound travels through, air, solids and water. 1. Take a tuning fork from the station. Holding the handle

of the tuning fork, strike it on a hard, solid surface. Gently move the move the fork toward the shallow pan of water and submerge the two tines (prongs).

Question 1: What happens and why? The vibrations from the tuning fork produce ripples, and maybe even splashes, in the water. The ripples are evidence of sound waves moving outwards from the source. As sound waves travel through a substance the molecules vibrate, each molecule hitting another and then returning to its normal state, “passing” the energy through the substance. Sound travels through air at about 340 m/s (~0.2 mile/s). However in seawater it travels at approximately 1600 m/s (~1 mile/s). Question 2: About how much faster does sound travel through seawater than it does air? 1600/340 = 4.7 times faster in seawater Question 3: Why would seawater be a better conductor of sound? As it is a liquid, water molecules are closer together than the molecules in air and therefore can transmit the sound energy faster. The dissolved salts (salinity) within seawater can also affect how the sound waves are reflected and refracted Sound can also be conducted through bone and soft tissue.

5. Strike the tuning fork again and hold it a few inches from your

ear. What you hear is your perception of the sound vibrations moving from the tuning fork.

6. Next you will test sound through your jawbone and the soft

tissue on your chin. Discuss with your group whether you think bone or soft tissue will change your perception of the sound from the tuning fork.

Question 4: What is your group’s hypothesis? Each group will provide an explanation of what they think may happen.

2009 SMILE Winter Teacher Workshop High School Club Activities WhaleWorks

7. Strike the tuning fork again and hold the tip of the handle to your lower jaw. Question 5: What do you hear/feel? The sound is more audible. The vibrations may even tickle slightly Question 6: Why do you think this is happening? The sound is more audible because the vibration is traveling through the bone and tissue of the lower jaw, channeling the sound to the middle ear. Because the molecules comprising these structures are more densely packed than the molecules in air, the sound travels faster and farther. Students may be surprised to discover that their lower jaw conducts sound faster. Land mammals, such as elephants, can easily see 100 feet ahead of them across open ground. If you have ever opened your eyes underwater whilst swimming, you will know that vision underwater is much more limited. Question 7: Thinking about this and what you have discovered at this station, how are marine mammals most likely to communicate and navigate? Why would this benefit them? Give examples. Example answer: Due to difficult vision underwater, marine mammals have adapted to communicate and navigate using sound. This aids feeding and communication between groups as not only does sound travel faster and farther underwater, marine mammals can transmit and receive sound more efficiently through their bodies. Examples include echolocation in dolphins – using specific frequencies of sound to determine distance from a target. Also whalesong – a series of clicks and different frequency moans which varies by whale species.

A toothed whaleʼs fat-filled jawbone conducts sound through the jaw to bones in the middle ears.

2009 SMILE Winter Teacher Workshop High School Club Activities WhaleWorks

STATION B: Blubber Gloves

This station will help you investigate the role of whale blubber. 4. Discuss with your group a prediction for how cold the ice in the dishpan is. Now

measure the temperature with a thermometer. Question 1: What is the temperature of the ice? The temperature of the ice will vary a few degrees above freezing point. Temperature will also vary depending on where in the ice the measurement was taken i.e. measurement taken in center of an ice pile may be warmer due to insulation The temperature of the North Pacific Ocean varies from 48°F to 64°F. Is the ice within this temperature range? Imagine the dishpan of ice as a representation of the North Pacific. 5. In your group, take turns putting a bare hand into the ice. Use a stopwatch to see

how long the temperature of the ice can be tolerated by each person. Record these results on the observation sheet below and calculate an average (in seconds) for the group. This average will be your control measurement.

NB: This is not an endurance test! Think of your hand as your whole body; as soon as it becomes too chilled, take your hand out and stop timing! 6. Next, have your group repeat the experiment using the following to cover hands:

a. A double-lined Ziploc bag (i.e. one bag inside another)

b. A rubber glove c. A rubber glove lined with a cotton glove d. A rubber glove lined with a wool glove e. A blubber glove

Record all your observations. If you have time, complete additional experiments using your own combination of hand coverings with available materials. Question 2: Which hand covering provides the most warmth? The blubber glove. If students have invented their own hand covering that potentially sway this result, however the blubber glove is still likely to be the warmest Question 3: What is your explanation for these outcomes? As fat molecules are larger, they are better insulators by creating larger air spaces between the molecules in a fatty solid, similarly to how Styrofoam keeps a cup of coffee warmer for longer.

2009 SMILE Winter Teacher Workshop High School Club Activities WhaleWorks

Marine mammals, like humans, are warm blooded. A human being without any protection in water that is 32°F can lose consciousness in around 10 minutes as heat loss is much greater in water than in air. Question 4: How do marine mammals survive in a cold ocean, such as the North Pacific? Marine mammals such as cetaceans, pinnipeds and polar bears all have a thick layer of fat (blubber) under the skin, which provides insulation from the cold. Blubber also serves as an energy store – abundant feeding periods allow marine mammals to store fat. During food scarcity, this fat store can be metabolized to maintain energy for survival. NB: Not all marine mammals have blubber, for example sea otters. Some rely simply on their fur for insulation; others use a combination of fur and blubber. Experiment observation sheet:

Hand Covering Time Until Chilled Group Average (Sec) Bare hand (control) Rubber glove Rubber glove lined with cotton glove Rubber glove lined with wool glove Blubber Glove Additional:

Body blubber is a key feature of the Northern Elephant Seal

2009 SMILE Winter Teacher Workshop High School Club Activities WhaleWorks

STATION C: Eat Like a Whale

At this station you will investigate different whale feeding strategies.

Skimmers Bowhead and right whales are examples of mysticetes (baleen whales) that feed by skimming the surface of the water with their mouths open, using baleen “combs” to filter out food.

Gulpers Some mysticetes, such as blue and fin whales, have pleats in their throat that help the throat to expand, allowing the whale to take in large quantities of both water and prey.

Bubblers “Bubble netting” is a strategy for catching fish unique to humpback whales. In a group of 5-15 whales, one whale will submerge and shriek an eerie sound while blowing bubbles in a circle formation. The fish become frightened and move close together.

Biters Ordontocetes (toothed whales), such as sperm whales and orca, are active hunters feeding on prey such as fish, squid and other marine mammals.

1. Assign each member of your group a feeding type: “skimmer”, “gulper”, “bubbler”

or “biter”. Have each type simulate their feeding strategy using the instructions below:

Skimmers: Move a comb through a pan of water filled with parsley. Remove the parsley by tapping it onto scrap paper.

Gulpers: Hold a comb in front of the open end of a Ziploc bag. Move the bag through the parsley water and gently squeeze the water back out of the bag through the comb a little at a time. Tap the remaining parsley out onto scrap paper. Do this until all the water is drained from the bag. Bubblers: Using straws, 2 or more students blow bubbles through the parsley water, working as a group to move the food to the center of the dishpan. Another student then brings a ziploc bag up from the bottom of the pan, through the center of the concentrated food. Use a comb to strain the parsley from the water and tap it out onto scrap paper.

2009 SMILE Winter Teacher Workshop High School Club Activities WhaleWorks

Biters: Using tongs and the water containing Styrofoam pieces, grasp “prey” out of the water. Place pieces onto scrap paper and record how much is captured per “bite”. In these simulations, the parsley represents krill, copepods and other zooplankton;

the Styrofoam represents fish, squid and seals. 2. With each feeding simulation, observe amounts of “food” collected and record

visual estimates on the table below. Weigh the amounts if scales are available. Try to repeat each simulation a number of times to work out an average amount of food per feeding type.

Feeding Type Amount of “Food” Collected Average Amount

Skimmers Gulpers Bubblers Biters Question 1: Using your results, which baleen feeding type is most efficient? Why? This answer will depend on the experimentation used by the students. The 3 baleen feeding strategies are likely to be very similar in outcomes, however the skimmers= strategy may work out best as it is a simpler method overall. Generally, this question should allow students to compare the different methods. Question 2: Which prey should toothed whales concentrate on? Why? Students should deduce that it is easier to grasp the Styrofoam pieces than the parsley with the tongs, thus toothed whales are better adapted to hunt larger fish, squid and seals.