Wildlife Migrations - Energetic Causes and Consequences
Abstract
Many species embark upon regular, long-distance journeys that are referred to as migrations. This
lesson will cover the biological and ecological drivers of wildlife migrations and the role
migratory species play in transferring energy and nutrients between disparate ecosystems. The
lesson begins with the students collecting data on humpback whale movements. They will
identify individual whales based on pictures of whales’ tails (flukes) and record where/when the
whales were (re)sighted. They will be asked to identify patterns among their observations and
draw conclusions about whether or not humpback whales are a migratory species. This will set
the stage for a general discussion about migration. Then, working in groups, the students will
learn about five different migratory species and they will measure out the distance of these
species’ migrations using paperclips. This will provide a foundation for discussing how and
where migratory animals transfer energy. Finally, the students will work in groups to research a
migratory animal in their state and they will draw a map of the species’ migratory route. Through
this lesson, students will learn about seasonal variation in natural resources, behavioral cycles of
organisms, predator/prey interactions, and conservation of energy. While doing so, they will
develop their observation and reasoning skills, and will engage in mathematics and geography.
Wildlife Migrations - Energetic Causes and Consequences (120 minutes)
Learning Objectives

Differentiate between migration and other types of movement.

Understand the drivers of wildlife migration, including seasonal variation in
environmental conditions and resources as well as biological cycles of organisms.

Understand the concept of conservation of energy and the role of energy in wildlife
migrations, including energetic causes and consequences of migrations.

Understand the role of migratory species in transferring energy between disparate
systems and the importance of predator/prey interactions.

Develop observation and reasoning skills.

Practice making simple mathematical calculations.

Gain experience drawing maps.
Grade 6 standards:
Strand 1: Inquiry Process > Concept 2: Scientific Testing (Investigating and Modeling)

PO 5. Keep a record of observations, notes, sketches, questions, and ideas using tools
such as written and/or computer logs.
Strand 1: Inquiry Process > Concept 3: Analysis and Conclusions

PO 1. Analyze data obtained in a scientific investigation to identify trends.

PO 2. Form a logical argument about a correlation between variables or sequence of
events (e.g., construct a cause-and-effect chain that explains a sequence of events).
Strand 2: History and Nature of Science > Concept 2: Nature of Scientific Knowledge

PO 3. Apply the following scientific processes to other problem solving or decision
making situations: observing, organizing data, inferring, comparing, measuring
Strand 4: Life Science > Concept 3: Populations of Organisms in an Ecosystem

PO 1. Explain that sunlight is the major source of energy for most ecosystems.

PO 2. Describe how the following environmental conditions affect the quality of life:
climate.
Grade 7 standards:
Strand 1: Inquiry Process > Concept 2: Scientific Testing (Investigating and Modeling)

PO 5. Keep a record of observations, notes, sketches, questions, and ideas using tools
such as written and/or computer logs.
Strand 1: Inquiry Process > Concept 3: Analysis and Conclusions

PO 1. Analyze data obtained in a scientific investigation to identify trends.

PO 2. Form a logical argument about a correlation between variables or sequence of
events (e.g., construct a cause-and-effect chain that explains a sequence of events).

PO 5. Formulate a conclusion based on data analysis.
Strand 2: History and Nature of Science > Concept 2: Nature of Scientific Knowledge

PO 3. Apply the following scientific processes to other problem solving or decision
making situations: observing, organizing data, inferring, comparing, measuring
Strand 4: Life Science > Concept 3: Populations of Organisms in an Ecosystem

PO 2. Explain how organisms obtain and use resources to develop and thrive in: niches,
predator/prey relationships

PO 3. Analyze interactions of living organisms with their ecosystems (limiting factors).

PO 4. Predict how environmental factors affect survival rates in living organisms.
Grade 8 standards:
Strand 1: Inquiry Process > Concept 2: Scientific Testing (Investigating and Modeling)

PO 5. Keep a record of observations, notes, sketches, questions, and ideas using tools
such as written and/or computer logs.
Strand 1: Inquiry Process > Concept 3: Analysis and Conclusions

PO 1. Analyze data obtained in a scientific investigation to identify trends.

PO 2. Form a logical argument about a correlation between variables or sequence of
events (e.g., construct a cause-and-effect chain that explains a sequence of events).
Strand 2: History and Nature of Science > Concept 2: Nature of Scientific Knowledge

PO 1. Apply the following scientific processes to other problem solving or decision
making situations: observing, organizing data, inferring, comparing, measuring
Strand 4: Life Science > Concept 4: Diversity, Adaptation, and Behavior

PO 1. Explain how an organism’s behavior allows it to survive in an environment.

PO 5. Analyze the following behavioral cycles of organisms: migration.
Materials (for 24 students)
24 Humpback whale photo ID lists**
9 Poster boards with humpback whale photos**
24 Animal information sheets (provided below)
24 Novel Migration Worksheets (provided below):
salmon (3), monarch butterfly (3), humpback whale (4), leatherback sea turtle (6), Arctic tern (8)
24 Research notebooks
5 Computers with Internet access
690 Large paperclips
Markers, crayons and/or colored pencils
Large paper
**Print from one of the websites suggested below.
During
snack
1. Pass out the humpback whale photo ID lists and have the students look at
them as they eat. (Suggestion: For the ID lists, only print pictures of the
whales that are used on the poster boards in the Engage activity.)
2. Ask what they see?
3. Help them recognize:
a. They are looking at pictures of whales’ tails (called a fluke).
b. Each fluke is different: some have more black/white, some have
unique markings, etc.
4. Explain that these are pictures of real whales collected by people all over
the world. Humpback whale flukes contain a unique pattern of black and
white that is as individually unique as our fingerprints. Scientists take
pictures of each fluke they see and use this data to track individual
animals. Has the whale has been spotted before? If so, when was it last
seen? Where? How many times has it been seen/how old might it be? If
it’s a female, has it been spotted with a calf (baby)/did it reproduce?
a. Photo identification is a great research tool because you do not
have to disturb the animal by capturing it and tagging it with a
unique identification number, and you can identify animals from a
distance.
Engage
30 minutes
20 minutes:
1. Scenario: The students are researchers trying to figure out the movement
patterns of humpback whales. They need to know which areas of the
ocean are most important for this endangered species, so they can help
policy makers establish marine protected areas (i.e., Where are the whales
found most often and does this vary over the course of the year?). They
will need to make observations about whale sightings and try to draw
conclusions about the movement patterns of humpbacks across the Pacific
Ocean.
2. There will be 3 stations around the room (or outside on the playground).
Each station represents a different region of the world - 2 tropical (Costa
Rica and Hawaii) and 1 temperate (Alaska).
3. At each station, there will be a poster board with pictures of whales’
flukes displayed. You can find pictures of whale flukes at:
http://www.splashcatalog.org/ OR
http://www.afsc.noaa.gov/ABL/Humpback/pdf/HW_Printable_Catalog_v
1.pdf
a. Round 1 (5 minutes) will simulate the first summer. The students
will have to go around to the poster boards at each station and
record which whales are there in their lab notebook using the
whale photo ID list. If they don’t feel like they were able to
identify all of the whales at each station in the time provided, tell
them not to worry. They will get a chance to share their data with
their classmates at the end of the activity. Researchers often
collaborate and share data with one another.
i. Begin with 1 whale in Alaska, 4 whales in Hawaii and 4
whales in Costa Rica. For example (the letters represent
different individuals):



Hawaii: A, B, C, D
Costa Rica: E, F, G, H
Alaska: I
b. Round 2 (5 minutes) will simulate winter. The teacher will put up
the next three poster boards with fluke photos at each station. The
students will go around to all of the stations again and make
observations about which whales are there. They record their
observations in their lab notebook.
i. For this round, 3 of the whales from Hawaii and 3 of the
whales from Costa Rica in round 1will join the 1 whale
from Alaska in round 1 in Alaska for round 2, 1 whale
from Hawaii in round 1 remains in Hawaii, and replace 1
whale from Costa Rica in round 1 with a new whale in
Alaska (total of 8 whales in Alaska and 1 in Hawaii). For
example (the letters represent different individuals):


Hawaii: A
Costa Rica: -

Alaska: I, B, C, D, E, F, G, J
c. Round 3 (5 minutes) will simulate the second summer. The
teacher will put the final three poster boards up at each station.
The students will go around to all of the stations again and make
observations about which whales are there. They record their
observations in their lab notebook.
i. For this round, 0 whales will be in Alaska, the 1 whale
that was in Hawaii for rounds 1 and 2 will remain in
Hawaii, 3 of the whales from Hawaii in round 1 and
Alaska in round 2 will be back in Hawaii, 1 whale from
Costa Rica in round 1 and Alaska in round 2 will be
replaced by a new whale in Costa Rica, and the remaining
4 whales from Alaska in round 2 will return to Costa Rica
(total of 4 whales in Hawaii and 5 whales in Costa Rica).
For example (the letters represent different individuals):



Hawaii: A, B, C, D,
Costa Rica: H, I, F, G, J
Alaska: -
d. Give the students 5 minutes to share and “analyze” their data, and
discuss their results with their peers.
10 minutes:
1. Ask the students what they observed.
a.
Most humpback whales were observed in the warm/tropical areas
(i.e., Costa Rica and Hawaii) in the winter and the cold/temperate
area (i.e., Alaska) in the summer.
b. Most individuals were seen at the same station both summers.
c. Some whales were only seen once. This raises the question:
Where did they go? What happened to them? Scientists face these
same uncertainties.
2. Ask the students why they might have observed these patterns. Why are
the humpbacks moving from place to place? Why are they in cold
temperate waters in the summer and warm tropical waters in the winter?
3. Ask if they know what we call these kinds of regular, long distance
movements? Migration
4. Provide background information on wildlife migrations using the
following prompts:
a. What is migration?
b. Why do animals migrate? What biological or ecological factors
cause an animal to migrate?
c. What triggers these migrations? What is the biological or
ecological cue?
d. What is a season? What makes seasons differ from one another?
e. What do you do in the fall, winter, spring, summer? Do you do
different activities? Do you eat different things in different
seasons? Why?
f.
Explore
30 minutes
What are the potential costs of migrations? Benefits?
10 minutes:
1. Have students get into groups:
a. Salmon (3 students)
b. Monarch butterfly (3 students)
c. Humpback whale (4 students)
d. Leatherback turtle (6 students)
e. Arctic tern (8 students)
2. Each group will be assigned a migratory animal and each student will be
given an information sheet for that species that describes fun facts about
the animal and its migration.
3. The groups will use paperclips to measure out the distance traveled by
their animal. Each paperclip will be equivalent to 100 miles.
a. Salmon – 1,000 miles round-trip (1,609 km)
(10 paperclips)
b. Monarch butterflies (4th generation) – 3,000 miles (4,828 km) (30
paperclips).
c. Humpback whale – 9,000 miles round-trip (14,484 km)
(90 paperclips)
d. Leatherback turtle – 12,000 miles round-trip (19,312 km)
(120 paperclips)
e. Arctic tern – 44,000 mile round-trip (70,811 km)
(440 paperclips)

Give your students a frame of reference that will make sense to them (e.g.,
100 miles is approximately the distance between Phoenix and Tucson,
twice the length of Rhode Island, etc.)

Encourage the groups to share the paperclip track building responsibility.
This is especially important for the Arctic term group - each student will
need to assemble ~55 paperclips to measure out the full 44,000 miles
traveled by a single tern.
20 minutes:
1. Have each group present the information on their animal information sheet
and the length of their paperclip track to the class.
Explain
10 minutes
10 minutes:
1. Introduce/review the following concepts:
a. Nearly all of the chemical energy on Earth came from the sun,
originally as solar energy.
b. Seasonal variation in resources (e.g., day length, water,
temperature, primary production, etc.) drives migrations.
c. Migration is energetically expensive and risky, but the benefits
outweigh the costs.
d. Some animals have to store large amounts of energy to complete
their migration (e.g., birds, humpback whales).
e. Animals are adapted to reduce energetic loss during migrations
(e.g., hydrodynamic body of humpback whale, Arctic terns
gliding on prevailing winds).
f.
Energy is neither created nor destroyed – only transferred.
g. Energy is critical to build tissues, hunt for prey, reproduce, etc.
(metabolism).
h. Energy is stored in the chemical bonds of biological tissues. It is
transferred from prey to predators, from plants to herbivores, and
it is broken down and released with decomposition.
i.
Energy is transferred between ecosystems via animal migration.
2. Engage the students in a conversation regarding how, when and where
their migratory species from the “Explore” section transfers energy
between ecosystems.
a. Salmon: Salmon spend most of their life eating and growing in the
ocean. When they are ready to reproduce, they migrate back to
their natal stream. During their migration upstream, salmon are
consumed by many predators, including eagles and bears, so the
energy acquired by the salmon in the ocean becomes part of the
terrestrial food web. After laying and fertilizing their eggs, many
salmon species die. Their decomposing bodies nourish the upland
streams where they were born.
b. Monarch butterflies - Monarch butterflies eat milkweed in
temperate latitudes. As the monarchs die, and subsequently
decompose, in transit to winter hibernating grounds, they transfer
the energy from northern milkweed plants to ecosystems
distributed between Canada and Mexico.
c. Humpback whales - Humpback whales filter feed tiny
crustaceans, plankton, and small fish from cold northern surface
waters of the ocean during the summer. Then, they travel back to
warm tropical breeding grounds in the winter. When they give
birth and shed the placenta, the energy stored in it, which was
acquired while feeding in high latitudes, is transferred to the
tropical ecosystem where it is a source of food for other marine
species. Also, when whales die, they bodies provide food and
habitat for benthic (ocean floor) communities thereby transferring
the energy they gained from feeding along the ocean surface to
communities in the deep sea.
d. Leatherback turtles - The energy they obtain from jellyfish in
northern waters is used to produce eggs. They migrate to tropical
and subtropical beaches (that are nutrient-depleted) to lay their
eggs. The eggs hatch and the remaining egg shells and yolk (built
from the energy derived from jellyfish) stay behind and nourish
the beaches.
e. Arctic terns: Arctic terns forage on land and in the sea. Energy
acquired in these ecosystems is transferred to other ecosystems as
they themselves become prey to predators on land and in the sea.
Expand
40 minutes
25 minutes:
1. Have students get into groups and identify animals that migrate in or
through their state. The Internet may be needed to research species.
Remind the students that migrations aren’t always long geographic
distances (e.g., they may be elevational).
2. Have the students identify the species as well as why, when, and where it
migrates, and where energy is acquired and transferred along the way.
3. They should record their findings in their research notebooks.
15 minutes:
1. Have the groups draw a map of their animal’s migration that includes
where energy is acquired and where it is released along the migration
route.
Evaluate
10 minutes
10 minutes:
1. With the remaining time, have students make up their own migratory
species and fill in the attached Novel Migration Worksheet that will help
them describe their species’ journey, including when, why, and where
their animal migrates, and where energy is acquired and transferred along
the way.
Novel Migration Worksheet
Name: ___________________________________
Date: ________________
Now, it’s your turn to create a species! Imagine that you just discovered a new migratory
creature and explain its migration. Use the questions/directions below to guide you.
1. What is the name of your migratory species?
2. Draw a picture of your species in the box below.
3. Why does your species migrate?
4. When does its migration begin? When does its migration end?
5. Describe your species’ migration, including where it goes.
6. Where does your species acquire its energy? Where does
your species transfer its energy to? How?
Wildlife Migrations - Energetic Causes and Consequences
General Background Knowledge
Wildlife migration is large-scale regular (e.g., daily, seasonal, annual) movement of
individuals from one place to another (Encyclopedia Britannica, National Geographic
Education). Animals migrate primarily to find food/water or to reproduce. The trigger for
the migration may be local climate, local availability of food or water, day length, or
biological cycles (e.g., reproduction) (National Geographic Education). Migration is
energetically expensive an can be dangerous, but the benefits outweigh the costs.
Migration can describe four distinct, but related concepts (Dingle and Drake 2007):
1. persistent, straight, movement behavior;
2. relocation of an individual on a greater scale (both spatially and temporally) than
its normal daily activities;
3. seasonal ‘to-and-fro’ movement of a population between two areas; and
4. movement leading to the redistribution of individuals within a population.
Migration can be either obligate, meaning individuals must always migrate, or
facultative, meaning individuals can choose to migrate or not (Dingle and Drake 2007).
Within a migratory species or a single population (i.e., group of individual animals of the
same species located in the same geographic region), all individuals may not migrate
(Dingle and Drake 2007). Complete migration is when all individuals migrate, partial
migration is when some individuals migrate while others do not, and differential
migration is when the difference between migratory and non-migratory individuals is
based on age or sex, for example (Dingle and Drake 2007).
Many of the best known wildlife migrations occur on an annual cycle, but some
organisms migrate daily. For example, many aquatic animals migrate vertically in the
water column (diel vertical migration), sometimes travelling several hundred meters
round trip (McLaren 1974). Some jellyfish migrate horizontally each day, traversing a
few hundred meters (Hamner 1981).
Migratory Animals Background Knowledge
Leatherback turtle: Leatherback turtles are one of the world’s largest reptiles, growing
up to 7 feet long and weighing up to two tons (National Geographic – Animals
(a)). They are a pelagic (open ocean) species whose diet consists primarily of
jellyfish and other gelatinous invertebrates (Fossette et al. 2010). Leatherback sea
turtles travel across entire ocean basins to feast on jellyfish blooms. Northern
latitude waters are more nutrient-rich than lower latitude waters, so there is more
primary productivity. Increased phytoplankton biomass (i.e., very small plants
that grow in the open ocean) leads to jellyfish blooms because phytoplankton are
a key food source for jellyfish (Mills 2001). Leatherbacks migrate nearly 6,000
miles one-way to feast on these blooms (National Park Service (a)). Then, after
feeding all winter, leatherbacks migrate back to tropical and subtropical beaches
to lay their eggs. They need the warm beaches to incubate their eggs and the
temperature of the nest actually determines the sex of sea turtle hatchlings
(National Geographic – Animals (a)). By consuming jellyfish in nutrient-rich
northern oceans and then migrating back to tropical and subtropical beaches to lay
their eggs that were are produced with the energy derived from the jellyfish, the
leatherbacks are transferring energy and nutrients between these two systems
(Bjorndal and Jackson 2003). After the turtles hatch, the eggs biodegrade and
provide essential nutrients to nutrient-poor low latitude beaches. This transfer of
energy and nutrients helps sustain nutrient-poor beach ecosystems that are vital to
many other plant and animal species (Hannan et al. 2007). Conservation note:
During their long-distance migrations the turtles are threatened by a number of
factors. In particular, leatherbacks cannot adequately differentiate between
floating plastic bags and jellyfish, so they sometimes eat plastic bags and end up
choking on them (Mrosovsky et al. 2009).
Humpback whales: Humpback whales travel as much as 10,000 miles (16,093 km) round
trip from cold temperate summer feeding grounds to warm tropical winter mating
and birthing grounds (Folkens et al. 2002). During the winter, when the whales
are in warm (sub-) tropical waters, adults do not eat, but live off their layer of
blubber (fat); the young calves feed on their mother's rich milk (Folkens et al.
2002). Humpbacks migrate at 3-7 mph with almost no rest along the way
(National Marine Sanctuary). During migrations, they cover over 1,000 miles per
month. When they die, whales become entire ecosystems for benthic (ocean floor)
communities. In this way they transfer energy from ocean surface waters to the
deep sea.
Monarch butterflies: Monarch butterflies depend on milkweed to lay their eggs and feed
their larvae (US Forest Service, National Geographic-Animals (b)). These larval
food plants grow in temperate parts of North America. Monarchs cannot
withstand the freezing winter weather in the northern and central continental
climates, so they migrate south to hibernate in Mexico and some parts of southern
California for the winter (US Forest Service). In the spring, they migrate back
north (US Forest Service). It takes four generations to complete the round-trip
migration: the 1st three generations only live 2-5 weeks a piece, the fourth
generation make the migration south and hibernates over winter (living up to 9
months) (US Forest Service). In the spring, after hibernating, they mate. The
males die and the females begin the migration back north. Before the females die
on the return journey, they lay their eggs. As the monarchs die in transit, they
transfer the energy from northern milkweed plants to ecosystems distributed
between Canada and Mexico.
Salmon: Salmon are born in freshwater streams (Groot and Margolis 1991). They
migrate to the open ocean where they spend most of their life eating and growing
in nutrient-rich cold waters (Groot and Margolis 1991). When it is time to
reproduce, they migrate back to their natal streams (Groot and Margolis 1991).
How they find their way back to their natal stream is still unclear, but their sense
of smell is believed to play a major role. Along the way, many salmon are
captured and eaten by other predators. Some of the most notable predators that
rely on salmon for their survival are bears and bald eagles. This food source helps
bears “fatten up” for the winter, so they can hibernate in their dens without having
to eat. After laying and fertilizing their eggs, the salmon die (Groot and Margolis
1991) and the energy contained in their tissues (derived from their time foraging
in the ocean) is transferred to the upstream ecosystem. This transfer of energy
“fertilizes” the base of the river food web.
Arctic tern: The Arctic tern makes the longest annual migration in the animal kingdom
(44,000 miles; 70,900 km) (Egevang et al. 2010). These seabirds spend their
breeding season in the Arctic where the summer days are long between May and
August. During the winter, November to February, they travel to the southern
hemisphere (Antarctic) where the days are long between November and February
(Egevang et al. 2010). Due to these incredibly long migrations, Arctic terns
experience two summers (National Park Service (b)) and see more daylight than
any living creature (including humans) on the entire planet! Along the way, they
forage on foods they have obtained from multiple ecosystems, thus transferring
energy between ecosystems up to 22,000 miles away! They conserve energy
along the way by gliding on prevailing winds (Egevang et al. 2010).
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df
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