Lesson 4 Whale Communication
Overview
Through the use of multiple senses, students engage in a variety of activities showing how
whales communicate with one another and navigate their environment. The diversity of
whales is explored as well as the effect of humans on whales.
National Science Education Standards
Content Standards K-4
Science as Inquiry: Abilities necessary to do scientific inquiry, Understanding about
scientific inquiry.
Life Science: The characteristics of organisms, Life cycles of organisms, Organisms
and environments.
Science and Technology: Abilities to distinguish between natural objects and objects
made by humans, Understanding about science and technology.
Science in Personal and Social Perspectives: Characteristics and changes in
populations, Types of resources, Changes in environments.
History and Nature of Science: Science as a human endeavor.
Content Standards 5-8
Science as Inquiry: Understandings about scientific inquiry
Life Science: Regulation and behavior, Populations and ecosystems, Diversity and
adaptations of organisms.
Science in Personal and Social Perspectives: Populations, resources, and
environments, Science and technology in society.
History and Nature of Science: Science as a human endeavor.
Ocean Literacy Principles
Principle 5: The ocean supports a great diversity of life and ecosystems.
Principle 6: The ocean and humans are inextricably interconnected.
Principle 7: The ocean is largely unexplored.
Performance Objectives
Students will:
• Understand the value of sound as a means of "seeing" underwater.
• Demonstrate how whales may use sound to keep in touch with each other and their
surroundings.
• Gain an appreciation for the complexity of whale communication.
Background
The ocean is a habitat where light does not penetrate very far. For whales however, this vast
3-dimensional world is far from dark. The ocean is illuminated by sound, which travels much
farther than light underwater. The sounds of waves and storms at the surface, of earthquakes
and underwater landslides, of schooling fish, and of whales fill the underwater world. Whales
use these natural sounds and sounds that they produce for just about every aspect of their
lives. In the next two lessons, students will be learning about the importance of sound to
whales. This section will provide background information on sound underwater and ways in
which whales use it to navigate, to hunt for food, and to communicate with one another.
Sound energy travels as a wave. The frequency, or number of waves that travel past the ear
in one second, is measured in hertz (Hz). Humans can hear sounds as low as 20Hz, or 20
waves passing the ear per second, and as high as about 20,000Hz. The intensity (loudness) of
a sound is measured in decibels (dB). The softest sound a human with perfect hearing can
detect is 0dB and the most intense sound a person can be exposed to without instant hearing
damage is 160dB. Whales have acute hearing and can hear a much broader range of
frequencies than people.
All whales produce sound. Just as no two species look or behave the same, no two species
make the same set of sounds. Toothed whales, like dolphins and porpoises, make click-type
sounds and most also produce whistles in the higher frequencies. Baleen whales, like blue
and fin whales, make a wide variety of lower frequency tones and upswept or downswept
calls.
The clicks that toothed whales make are used for echolocation. This is a method of
navigation underwater in which the whale produces a sharp, impulsive sound like a clapping
hand and then interprets the echoes from that click off of objects in the water. These echoes
returning from all directions help the whale to form a 3-dimensional picture of its
environment. Like an ultrasound used to create a sonogram of an infant in the womb, highfrequency clicks give a large amount of detail and can even be used to investigate the inner
layers of certain objects, like fish.
Dolphins, beaked whales, and porpoises generally make high-frequency clicks. The trade-off
of higher frequencies underwater is that they don’t travel as far as lower frequencies. Sperm
whales make clicks that are lower and much more powerful than dolphins. Although they
may not provide the high resolution of higher frequency clicks, these clicks travel much
farther and help the whales to find patches of food from greater distances.
In addition to clicks, most toothed whales also produce whistle-type sounds. These are used
for communication between animals in a group. Bottlenose dolphins, for example make a
wide variety of whistles to communicate with one another. Each dolphin also makes its own
unique sound called a signature whistle. Scientists studying these signature whistles believe
that they may be like a dolphin saying its name in order to identify itself to pod mates.
Whale researchers use sound recorded through underwater microphones, or hydrophones,
as a method of detecting, tracking, and identifying whales. One way to analyze these signals
from the hydrophone is to digitize them using a computer and to display them as a
spectrogram. A spectrogram is a way to visualize sound like a picture. The computer draws
an image of a sound over time that puts higher frequencies above lower ones, like the sheet
music that musicians read. It also shows the intensity of the sounds by color or contrast. To
see spectrograms of the clicks, whistles, tones, and sweeps produced by 40 species of marine
mammals, please visit the Voices in the Sea website (http://www.voicesinthesea.org).
Fig.1 Spectrogram of bottlenose dolphin clicks and whistles. Frequency is displayed top to
bottom while time is displayed left to right. More intense sounds are darker in shade.
Humans also introduce sounds into the ocean. Exploration for undersea natural resources,
naval sonar, geophysical research, marine industry, fishing activities, and ships of all types
produce sounds. In some areas, these man-made sounds are so loud that they may have an
effect on a whale’s ability to communicate or to navigate. While the effects of increasing
noise pollution in the ocean are not well known, certain types of sound, like high-intensity
military sonar, appears to cause injury to highly-sensitive species like the beaked whales. This
is another reason that it is important to understand how whales use sound.
In the Videos
Beaked whales and man-made sound, Meet the beaked whales, The whistles of the
bottlenose dolphin, The song of the humpback whale, The voice of the blue whale, and
Coda, the language of the sperm whale.
Key Words for Whale Wall
Echolocation, High-frequency, Low-frequency, Songs, Noise Pollution
Materials
• Paper, pens, crayons to create art and words for whale wall
• CD player with fast paced rock or pop music ready to play
• Whales: Voices in the Sea website projected onto screen or wall
• Student Journals
• 4 Blindfolds
• Paper, pens, crayons to create art and words for whale wall
Procedure
During Class:
Once students have seated ask them to choose whales to listen to from the menu. Be sure to
pick a variety of species in order to hear the diversity among whale sounds and see the range
of spectrograms. Encourage students to sketch a few of the spectrograms in their Student
Journals paying attention to the upsweeps (lines moving up), downsweeps (lines moving
down), and pulses (bold vertical lines).
Remind students that whales have special adaptations that help them thrive underwater even
though they breathe air like us. One of the most important adaptations whales have
developed is their ability to create pictures of their surroundings using sound, instead of light
like us! Explain the use of sound as a method of seeing underwater. Whales use sound to
locate food, as an aid in navigating through the vast ocean, as a way to keep in touch with
one another, and as a means to attract a mate. Scientists have learned that some whales can
use sound not only to see objects underwater, but also to look right inside them, like
Superman with X-ray vision!
Activity 1: Full of Hot Air (5 Min.)
Discuss how scientists believe whales produce sound underwater. Whales produce the
loudest sounds made by any animal! While scientists know that some whales produce these
sounds without releasing air, just how they do it remains a mystery. When humans
communicate verbally we expel air, whales do not. This activity demonstrates that some
whales produce sounds underwater without releasing air.
1. Instruct students to take a deep breath, plug their nose and try to communicate with
another student without releasing any air.
2. Give 2 minutes to engage in this activity.
Activity 2: Pod Squad (10 Min.)
This activity demonstrates the great density of information contained in sound.
1. Have the class form a circle facing inward.
2. Blindfold one student and put him or her in the middle of the circle.
3. The person in the middle of the circle will be trying to identify other people in the
circle using sound only.
4. Spin the blindfolded person twice, then point him or her at someone in the circle.
That person is to say, 'Hi _____' (blindfolded student's name) in his/her normal
voice. (Try to pick one student who is known well to the subject and someone who
is not.)
5. Using this information, the blindfolded student is to make his/her best guess at who
is talking to him/her, then respond 'Hi ______' (the name of who he/she thinks it
is)
6. Let several students try, giving each the chance to identify a few classmates. Discuss
the following questions with the class.
• Although each person in the circle said the same two words, were students
surprised with their success in identifying people in the circle?
• What were some of the things that they could tell about the speaker, just in
those two words? (Male or female, age, identity, are they sick or healthy, were
they smiling or laughing, are they a friend, where are they in relation to the
blindfolded student?)
Using sounds of many types (clicks, whistles, songs, codas) whales can determine many
things about each other and their surroundings without having to use their eyes. 100-foot
visibility underwater is extraordinarily rare. The underwater world is often too dark or
murky to rely on eyesight alone.