THE LIFE CYCLE OF THE SALMON


 In this lesson you will use the internet to research information about salmon and their life cycle. With your results you will then write a creative writing piece about a salmon and it's journey from egg to adulthood

 

Introduction


Salmon are fish are found  in moderate climates and in clean waters. Salmon are also native to the Northwest and have been spawning in the same streams for hundreds of years. This is a type of fish that spends its early life in fresh water, moves into the ocean where it matures and then returns to fresh water to spawn. Another name for this kind of fish is an anadromous fish.

Types of Salmon


Life Cycle Stages

There are seven stages in salmon's life :

Egg Stage:

A salmon's life begins as an egg. Salmon eggs are reddish orange in color. Salmon eggs are laid in gravel nests that hide and protect the eggs. The salmon eggs take at lest  50 days to hatch and can take longer depending on the temperature of the water. The colder the water the longer it takes for the fish to hatch.

Fertailzed salmon eggs

Alevin Stage

Once an egg hatches it is called an alevin. An alevin is unable to swim and is too strong to fight the current of the river. In order for an alevin to survive it must still stay hidden in the gravel of the riverbed. Alevin's have a yoke sack attached to them and that is their only source of food for weeks.

Salmon Alevin

Fry Stage

After a alevin has used up it's yoke sack it is called a fry. A fry is about an inch long and is able to finally swim and explore it's river. A fry has to find it's own food and is very vulnerable to predators.

Salmon Fry

Parr Stage

Once a fry has grown to around 2 inches it is called a parr or a fingerling. A parr has a tremendous appetite and is constantly feeding. During this time the parr begins to swim towards the ocean.

Salmon Parr

Smolt Stage

By the smolt stage a salmon has migrated itself to towards the coast and is living in estuaries. Estuaries are places where salt water and fresh water meet. This is the stage where salmon begin to undergo changes that will allow them to live in salt water instead of fresh. A salmon that has made it this far along the journey is very lucky to have survived.

Salmon Smolt

Adult Stage

The salmon head straight for their hereditary feeding grounds and live in large, loose schools. They stay here for 1-5 years, depending on the species. They face many hazards from hungry predators. When the time comes they return to the streams where their life began.

An adult salmon

Spawning Stage

 When the time comes a salmon will begin to return to the stream from which it was born. During this stage the salmon will stop eating a begin to live off of it's fat reserves. They will swim all the way up stream and back to the same river they were born. After they return the female salmon dig nests in the gravel that are called redds, they then lay thousands of eggs. After the eggs are laid male salmon spread sperm or milt onto the eggs to fertilize them. Then the female salmon goes back and covers her nest. Of all the eggs laid by the female salmon only 1-10 will live to adulthood. After spawning the salmon then dies to make way for a new generation.

A pair of spawning salmon

Creative Writing Assignment

For your assignment you will write a 2-3 page creative paper on the life of a salmon from egg stage to spawning stage. Your objective is to prove your knowledge of  the life cycle of the salmon in a creative way. Use your imagination to decide what a salmon is feeling and thinking at certain stages in it's life. Also feel free to make up adventures for your salmon but be sure to stay true to the facts mentioned above. Have fun with it!

Rubric

Your assignment will be graded according to the following rubric:

  Excellent Good Fair Poor
Creativity Tells the life cycle of a salmon as a story with a strong beginning middle and end with a strong plot. Tells the life cycle of a salmon as a story with a evident beginning middle and end with a evident understanding of plot. Tells the life cycle of a salmon as a story with a weak beginning middle and end with weak plot. No story just facts, no real evidence plot.
Use of Research Included facts from the provided research and extra research form resource list and comprehension evident in paper. Included facts from the provided research understanding of concept evident in paper. Included some facts from the provided research and understanding of concept evident in paper. Included few facts from the provided research and limited understanding of concept evident in paper.
Conventions Correct grammar, spelling and punctuation. Same point of view used through the entire paper Correct grammar , spelling and punctuation used through out most of the paper, but errors do not distract. Same point of view through out paper. Correct grammar , spelling and punctuation used through out a portion of the paper, but errors are distracting from main point of the paper.  Grammar , spelling and punctuation error through out the paper, errors are a major distraction from main point of the paper.

Total Points: 40 pts.

 


Resources:

Here are some links for any further research you may want to do:

·         http://library.thinkquest.org/05aug/00548/species--life%20cycle.html

·         http://www.fishex.com/seafood/salmon/salmon-life-cycles.html

·         http://www.oregonwild.org/fish_wildlife/wildlife-pages/coho-salmon?gclid=CLTHj4ia86wCFYYZQgodoGJHeA

·         http://www.youtube.com/watch?v=5DqjsWsY8-g

·         http://www.streamnet.org/SLC.html