These books are just a few possibilities. There are many other
possibilities--use whatever you have on your shelves already or what you
can get from your library. At minimum, you will probably want to
get a life cycle book, a book that contains photographs of salmon, and
maybe a book on migration.
Salmon Stream by
Carol Reed-Jones (A picture book telling the life cycle through a cumulative
rhyme and gorgeous pictures. Lots of good information for the
parent at the end. There is one remark that parents may wish to know
about: "This is the rain that swells the rivers, and sends the
message that nature delivers to salmon to send them home to
spawn,...." We just used it to discuss instinct and how God
created the salmon to know when it was time
head back to their home stream. This was in-line with a couple
references in the book to the fish instinctively knowing when it was
time to head to the ocean and how they obey "the voice of instinct"
when they head back home.)
Salmon Creek by Annette LeBox & Karen Reczuch
(A picture book telling the
life cycle of Sumi, a coho salmon. At the end, there is
information on the many threats to salmon, a glossary, a reading
list, and
a list of some easy ways children can help.)
Swimmer
by Shelley Gill (A picture book telling the life cycle of
Swimmer, a Chinook salmon in Alaska; could be a unit study in itself!
In addition to the story and beautiful illustrations, each page
is filled with details relating to both the salmon and the Native
Alaskans. Near the end of the story, some information at
the bottom of the page refers to modern salmon having "evolved over
50 million years ago," etc. You could easily skip
over this or use it as a spring board to discuss your beliefs.)
Sockeye's Journey Home: the Story of a Pacific Salmon
(Smithsonian Institute) by Barbara Gaines Winkelman (A picture
book of part of the life cycle of the sockeye salmon. This
story begins when the salmon is about three years old and living in the
ocean, getting ready to head back to the home stream. This book
does not contain information on the early stages of the life cycle.)
The Magic School Bus Goes Upstream: A Story About Salmon Migration by Joanna Cole
Come Back, Salmon: How a Group of Dedicated Kids Adopted Pigeon Creek and Brought it Back to Life by Molly Cone
A Salmon Story by Rita Ramstad. (beginning reader: 12 pages, with 10-12 words per page, and similar in size to a BOB book.)
Red Tag Comes Back by Fred Phleger. (A Science I Can Read book; a 64 page reader that tells the life cycle of the salmon.)
Atlantic Salmon by Bianca Lavies (Note: At the
bottom of the third page, she does say that "Fish are an ancient line
of animals, the first vertebrates...to have appeared on earth."
The last pages talks about how ancient peoples thought the life
cycle was "magical" and that they fish died in the spring and came back
to life later. Every page is full color photographs showing the
salmon up close in various stages of its life.)
Life Cycle of a Pacific Salmon (Life Cycles
series) by Jason Cooper (24 pages, photographs of the
various stages. Text is large print, and not too overwhelming.
Key words are in bold print. Glossary in back.)
The Journey: Stories of Migration
by Cynthia Rylant (Contains information on other migrating
animals: locust, whale, eel, butterfly, caribou, and tern.)
Where Have all the Pandas Gone? Questions and Answers About Endangered Species
by Melvin and Gilda Berger. (There is a reference on page 3, in the
introduction, to dinosaurs having been "driven to extinction when an
asteroid struck our planet some 65 million years ago" and giant
mammoths that "died out about 10,000 years ago.") Lapbook
adult salmon -- a stage in the
life cycle of the salmon. Full grown salmon live in the
ocean before they migrate back to their home stream to reproduce.
alevins (al uh vins) -- a stage in the life cycle of the salmon. A baby salmon newly hatched from the eggs--they have a yolk sac
anadromous -- fish that migrate from fresh water to salt water. Salmon are an example.
camouflage -- The ability of an animal to blend in with its surroundings because of its markings and coloring
estuary -- the coastal area where the salty waters of the ocean mix with the fresh waters of a river.
fingerling -- another name for a young salmon.
fresh water -- water that contains very little salt, usually found in rivers, lakes, and ponds
fry -- a stage in the life cycle of the salmon. Small salmon after they have used up their yolk sac.
juvenile salmon -- a
stage in the life cycle of the salmon. Young salmon that have
made the journey to the ocean, where they will grow until adulthood.
life cycle -- the stages and changes that an animal goes through from the beginning of it's life to the end.
migrate -- to travel from one location to an area, periodically or seasonally.
milt -- the milky substance a male salmon squirts on the eggs to fertilize them.
parr-- a stage in the life cycle of the salmon. Small salmon fry that have developed camouflage markings called parr marks.
redd -- nests made by a female salmon
smolt -- a stage in the life
cycle of the salmon. Salmon that's ready to make the migration
from the stream to the ocean. At this stage, a salmon's body has
developed to allow it to make the change from fresh water to salt water.
spawn -- breed, reproduce Geography
Atlantic Salmon -- Below is a list of just a few of
many places where salmon live that you might locate on a map or
choose to learn about. If you live near a salmon run, you may
wish to learn more about it instead.
Pacific Salmon -- A few places you might locate on a map or choose to learn about include: Pacific Ocean Columbia River (British Columbia/Washington/Oregon) Snake River (Wyoming/Idaho/Oregon/Washington) Fraser River (British Columbia, Canada) Copper River (Alaska) Skeena River (British Columbia, Canada)
Science Rabbit Trail: As you discuss rivers and their flow into other rivers and/or ocean, you may also wish to introduce the concept of watersheds and drainage basins.
A watershed is the area of land into which water flows (or is
"shed," hence the name). When it rains or snows, the waters
gather into streams, rivers, and lakes. These often eventually
flow into larger rivers, which in turn flow into even larger rivers,
and eventually into the ocean.
For example in the area where I live, we have small streams which flow
into a larger river, so we are in that larger rivers' watershed
drainage area. That larger river flows into the Ohio River, so we
are in the watershed drainage area of the Ohio River Basin as well.
The Ohio River eventually flows into the Mississippi River, and
so we are also in the watershed drainage area of the Mississippi River
Basin too.
The areas in which the Pacific salmon and the Atlantic salmon live have
similar watershed and river basin systems. This may be a topic
you wish to further explore.
You will likely find that you too are located in a similar system, and
you may wish to learn more about it. You may wish to demonstrate
the concept of your watersheds (or those of the salmon if you explored
those), by using Venn diagrams where the circles are within one another.
The genus name for the Atlantic salmon is salmo, and means "jumper."
Atlantic
Salmon (salmo salar) is most prolific of all salmon. They are
silvery in color with large black spots. They average 17 to 22
lbs. in weight, but can reach 65 lbs. After spawning, about 1 in
10 will once again make the migration back to the ocean and later
return to their home streams to spawn again. They live in the
North Atlantic Ocean from North America to England and the eastern
coastline of Europe.
Pacific Salmon (Genus
Oncorhynchus)
The genus name for the Pacific salmon isOncorhynchus,
and means "hooked
snout." There are six species of eastern Pacific salmon.
(Note some books refer to only five. After reading the lesson
about Steelhead Trout, you'll understand why.)
Chinook (Oncorhynchus tshawytscha): Chinook salmon are the largest of the Pacific salmon. They
are lightly spotted on their back, which is bluish-green. They
live 5 to 7 years and can weigh up to 120 lbs., but are usually around
30 lbs. They are prized game salmon (meaning they are the ones
sport fisherman love to catch). Because they are the largest of
the Pacific salmon, they are often called King Salmon. They are the least abundant of the pacific salmon.
Chum (Oncorhynchus keta):
Chum or keta salmon have black spots and faint bars on
their sides, which are silver. They live 3 to 5 years and weigh
up to 10 lbs.
Coho (Oncorhynchus kisutch):
Coho salmon are silver in color. They live about 3 years
and weigh up to 15 lbs. They too are a popular game fish for
sports fisherman.
Pink (Oncorhynchus gorbuscha):
Pink salmon are the smallest of the Pacific salmon. They
weigh up to 5 lbs. and live only two years. They have silver
bodies and have many dark spots on their backs. Of the Pacific salmon species, the pink are the most plentiful.
Sockeye (Oncorhynchus nerka):
The sockeye salmon are bluish-silver in color when they are
in the ocean maturing. When they start the migration back to
their home stream, their bodies turn red and their head takes on a
greenish color with orange eyes. For this reason they are
sometimes called Red Salmon. They weigh up to 7 lbs.
They live about 4 to 5 years. They are thinner
than other species of Pacific salmon. They are the most
sought after
of the Pacific salmon because of their flavor.
Steelhead Trout (Oncorhynchus mykiss).
The Steelhead, or Rainbow, Trout was until recently classified as
an Atlantic salmon (Salmo gairdneri). In 1988, modern technology
allowed scientist to determine that the steelhead was more closely
related to the Pacific salmon and so it was voted to change the genus
and species name from Salmo gairdneri to Oncorhynchus mykiss.
These species of the Pacific salmon can be found in various places
along the coastline of southern California to the Bering
Sea.
As the salmon make their way back to their home stream to spawn, the
male of some of the species of salmon change. They do not eat
(they rely on what their bodies have stored up before the journey
began). Their body colors change (for example, sockeye develop
greenish colored heads and red bodies). Their mouth becomes more
hook shaped. Their backs may develop a hump. These changes
signal to the females that he is ready to spawn (reproduce).
Most Pacific salmon die within a week or two after they
return to their home stream and spawn. This trait of dying after
reproduction is called semelparity. The steelhead trout salmon
is the exception of the Pacific salmon, having the ability to repeat
spawning without dying.
Diet (What do salmon eat?)
Salmon are carnivores, meaning that they eat meat. They eat plankton, fish, squid, shrimp, etc.
Predators (What eats salmon?)
Salmon are eaten by man, bears, other fish, and birds like eagles and
kingfishers. Because many salmon die after spawning, home streams
are littered with decaying fish during spawning time. Bears,
eagles, wolves, foxes, ferrets, and other animals take advantage of
these easy and abundant meals.
Life cycle of the Salmon:
A spawning female Pacific salmon digs a nest, called a redd, in the gravel of a stream, where she lays hundreds of reddish eggs, each about the size of a pea. After the eggs are laid, a male salmon fertilizes them by squirting them with milt.
After that, the female gently covers the eggs with gravel.
The female and male repeats this in different areas of the stream
(except for the sockeye salmon, which only makes one redd), until
thousands of eggs (2,000 to 10,000) have been laid and fertilized. The male Pacific
salmon soon dies after he fertilizes the eggs (except for the steelhead
trout, which will once again migrate to the ocean and later return to
spawn again.
The Atlantic salmon are similar, except (like the
steelhead trout) the Atlantic salmon do not die and again migrate
and return to re-spawn. This characteristic of dying after
spawning is called semelparity.
The eggs remain hidden for up to 4 months before hatching as alevins. Alevins are tiny fish with a large yolk sac
attached to their bellies. This yolk sac provides food as the
baby fish grows, so it does not need to find food. Once the yolk
sac is used, the small fish are called fry. Some kinds of salmon at this stage develop parr marks, and are so then called parr
instead of fry. The parr marks help to camouflage them.
Some Pacific salmon are in this fry/parr stage briefly before
migrating to the ocean; others a year. Atlantic salmon stay in
this stage for 2 to 6 years.
By the time the fry/parr are ready to migrate to the sea, their
bodies start changing to allow them to make the move from the fresh
waters of the stream where they were born to the salty waters of the
ocean to where they will migrate. They are now called smolts.
One of the changes is in their coloring. Their bodies change from
brownish-greens that help camouflage them in a stream to a more silvery
color to help them hide in the ocean. Their blood makes changes
that will allow them to need less oxygen in the ocean (there is less
oxygen in the ocean than in streams). The salt pumps in their
gills also begin to change. In streams, the salt pumps act to
keep too much salt from leaving the fish. In the ocean, the salt
pumps act to remove the excess salt of the ocean. Isn't it
amazing how God designed the salmon to be able to change at just the
right times to
allow them to spend part of their life in freshwater and part of their
life in salt water! The changes the salmon go through would
be like what it would take for us being able to breathe
underwater!
Rain is often the signal to the smolts that it is time to make the long
journey downstream. They travel at night, and rest by day.
If the smolts are delayed (like at a dam), they may lose the urge
to migrate and they do not complete the cycle by spawning.
Once the smolts arrive at the estuary,
the land where the fresh water of the river meets the salty water of
the ocean, they may linger to get used to the salty water. Their
getting used to the salty water is called smoltification.
Once out in the ocean, they are considered juvenile salmon.
They spend several years in the ocean, growing and maturing into
adult salmon. They migrate hundreds or even thousands of miles
during this time.
At some point (and scientists are unsure of what triggers it), the
adult salmon know it's time for them to migrate back to their home
streams where they were born. They make their way back to the
estuary where they entered the ocean to begin the salmon run,
the journey home. Once they start swimming back to their home
stream, they do not eat. They rest in pools of water to regain
strength for the upstream journey. They often have to jump over
obstacles, such as waterfalls. The instinctive drive to return
home is so strong that they are willing to risk all to go back, and
some die trying.
Once they make it back to their home stream, they spawn and the cycle begins again.
Diary: Have your student to pretend he is either an Atlantic or
a Pacific salmon and have him write a diary of his experiences growing
up, traveling to the ocean, his life in the ocean, and his journey back
to his home stream. Remind him to use proper names for the stages
and to note various geographic locations.
Art
Drawing: Have your student draw and label the stages of a salmon's life cycle.
Combination of Language Arts and Art
Comic Strip: Have your student to create a comic strip that depicts the life cycle of a salmon.
Comic Strip Creator
Migration
Many animals migrate
each year, that is move from one place to another for an extended
period of time and then later return. Often they migrate for
breeding purposes, though some migrate to find food. Can your
student think of different animals that migrate? Some birds
(Canadian geese, loons, bald eagles, robins, whooping cranes, arctic tern), monarch
butterflies, caribou (reindeer), some whales (humpback, gray),
American silver eels, etc. The animal that migrates the furthest is the Arctic tern, a
bird which lives at the North Pole during the summer but migrates all
the way to the Antarctic in the fall!
As mentioned, many kinds of fish migrate. Fish that migrate can be divided
into three categories: diadromous (die-ad-ruh-mus),
potamodromous, and oceanodromous (oh-show-nod-ruh-mus).
1) Diadromous fish travel between salt and fresh water.
2) Potamodromous fish travel within fresh water only.
3) Oceanodromous fish travel within salt water only.
Diadromous fish can be further subdivided into three more categories,
depending on what part of their life cycle they are in freshwater and
salt water: anadromous (uh-nad-ruh-mus), catadromous
(kuh-tad-row-mus), and amphidromous (am-fid-ruh-mus).
Anadromous fish
live mostly in the ocean, but return to freshwater to breed.
Salmon are anadromous, hatching in freshwater streams, spending
much of their lives in the ocean's salty waters, then returning to
their home stream to spawn.
Catadromous fish are opposite, they live in freshwater, but go to the ocean to breed.
Amphidromous fish
travel between salt water and freshwater regularly at some point in
their lives, but not for breeding purposes. Source: Wiki
Here is a map
that shows the area in which the different kinds of Pacific salmon roam
while in the ocean. As you can see, salmon may travel thousands
of miles before returning to their home stream.
Destruction of part of an animal's migratory route can lead to great numbers of
the species dying. This has happened to the salmon and we will
talk about endangerment and extinction later.
Go to the One World Journeys website to see a slideshow
presentation about salmon. Once there, choose either Highband
(broadband/satellite) or Lowband (dial-up), then click on "Saga of the
Salmon" to join the exhibition. You may wish to view this
slideshow after discussing the threats of endangerment and even
extinction that salmon face. Preview for suitability. Homing Instinct
Scientists are not sure how how fish like salmon know how to return to the very stream in which
they were born. Most agree that once the fish find their way from the ocean to the
estuary for their river, that the salmon use their sense of smell, but
how they find their way around the ocean is a subject of debate. Some of the different theories are how
salmon might use celestial navigation (use the stars to tell which way
to go), might follow food, or might be able to detect the earth's magnetic
fields. This might be an interesting topic for a research paper for an
older student.
The urge to return home is called "homing instinct." You may have
heard stories of cats and dogs that move with their families hundreds
of miles away, only to leave the new home and somehow find their way
back to
their original home. They were able to use their instincts to
return home. Instinctual behavior is a trait that an
animal is born with and is not learned. God designed animals to have
instincts that tell them what to do and when to do it. An
example of a natural instinct would be that a dog is born with the knowledge
to lie down when tired. A learned instinct would be for the dog
to learn to lay down when commanded to. Numbers
For every 8,000 eggs produced, 4,500 alevin survive, from which 650 fry
survive, from which 200 parr survive, from which 50 smolt survive, from
which only 2 spawning adults survive (who produce thousands of eggs).
Source: Wiki
For more numbers, see the Endangerment and Extinction section below.
Endangerment and Extinction
Discuss with your student what it means for animals to be endangered or extinct.
Both the Atlantic and the Pacific salmon populations have declined
drastically and steadily. Stream conditions have to be just
right for the fish to
lay their eggs and for the newly hatched fish to survive. The
water especially needs to be fresh, clear, and cool. In
most places where salmon spawn, conditions are now less than
ideal. Streams
have become polluted. Dams have been built on the rivers used
by the salmon, thereby limiting the salmon's return to their native
areas. People have cut down trees along the rivers, so that the
trees no longer cool the river. Logging and other activities have
allowed silt and sand to muddy and thicken the streams.
In the Snake River area of the Pacific Northwest alone, "not long ago, before any dams were
constructed, up to 16 million salmon and steelhead would return in any
given year......Today, all runs of salmon and steelhead on the Snake
River are either extinct or listed under the Endangered Species Act.
Last year only three sockeye salmon returned to their spawning grounds
in Idaho." Source
In the New England area of the United States alone, "Historic Atlantic
salmon abundance in New England probably exceeded 30,000 returns
annually. Overfishing and habitat destruction resulted in a severely
depressed US population restricted to Maine and by 1950 with adult
returns of just a few hundred fish in a handful of rivers.
Hatchery-based stock rebuilding occurred from 1970-1990 reaching a peak
of 5,624 fish in 1986. A widespread collapse in Atlantic salmon
abundance started around 1990. In the past decade, US salmon returns
have averaged 1,600 fish and returns in 2005 were 1,320 fish." Source
To say the least, these numbers are alarming!
At the end of the book, Salmon Stream
by Carol Reed-Jones, there are addresses for several organizations to
which your student could write to get more information on the
conservation efforts to save the salmon. Here are a couple you
can visit on the Internet:
What is the difference between freshwater and salt water?
All water contains some salt. Freshwater, however,
contains
less than 1% salt and generally does not taste very salty. Have
your student get a small cup of water and take a drink--does it taste salty? Probably
not. Add a pinch of salt and take a sip--does it taste salty now?
Perhaps a little. What about if you add a teaspoon? A
tablespoon? Yuck!
Have or help your student make a list of general places that are
freshwater. Included in this list might be streams, rivers,
lakes,
ponds. Can he name specific places? This list might include
Grandma and Grandpa's Pond, the Mississippi River, Lake Erie, etc.
Research and learn more about specific freshwater places.
(Perhaps one on the list or others, such as the Great
Lakes--which makes up 22% of the world's fresh water)
Now have your student make a list of general places that he could find
salt water. This list will probably be short and list
only oceans, though he might recall that the Red Sea and the Great
Salt Lake of Utah are also salty. You may wish to take
this time to review the name of the oceans--can your student name all
of the oceans? They are: Atlantic,
Arctic, Indian, Pacific, and the Southern Ocean. Some teach
this last ocean as the Antarctic Ocean. However, in 2000, the
name Southern Ocean was given to the waters surrounding Antarctica and
north to 60 degrees latitude.
A cubic foot of saltwater contains over 2 pounds of salt. So what
makes oceans salty? As rivers flow toward the sea, they pick up
mineral salts and carry them along until they are emptied into the sea.
Now, this river water is not very salty. However, as water
from the oceans evaporate, the salt stays behind in the waters.
The remaining waters get saltier with time. Source: Enchanted Learning
The current saltiness of the sea is yet another bit of evidence for a young
earth--if the earth were indeed millions or billions of years old, it would be far
saltier than it is today. Parents, you may wish to read this Answers in Genesis article.
Rivers and streams are not the only source of the ocean's salts,
however. Hydrothermal vents in the floor of the ocean often
spew out salt minerals into the waters.
If all the salt from the ocean were removed and spread out over the
land, it would form a layer more than 500 feet thick! Source
Salt from the ocean is comprised of over 80 chemical elements and is so
complex that scientists cannot reproduce it exactly. Source How amazing our God is! Just for Fun!
If you are using this salmon study in a group setting, here is a fun activity for the students to learn how salmon might use their sense of smell to travel back to their home stream.
Materials and information
on this website belong to the original composers. It may be used for
your own personal and school use.