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Author Topic: How do fish reproduce?  (Read 9005 times)

Offline chat250

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How do fish reproduce?
« on: 27/06/2003 19:34:14 »
PLEASE HELP


 

Offline Quantumcat

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Re: How do fish reproduce?
« Reply #1 on: 28/06/2003 04:22:12 »
Usually, the female lays a batch of unfertlized eggs on a rock or something and the male will swim close to them and spray out sperm and the sperm will fertilize the eggs.

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Offline Exodus

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Re: How do fish reproduce?
« Reply #2 on: 28/06/2003 11:24:47 »
The following information comes courtesy of http://www.fish.washington.edu
http://wwwndo.ak.blm.gov/outdoordays/f2.htm




:)Salmon are used as an example - The female returns to the river she was born in to lay up to 1,000 to 10,000 eggs depending on the species and size of the fish. The eggs are fertilized by a spawning male and covered by gravel by the female for protection. Soon after the spawning the adults will die.

:)The eggs are deposited into nests called redds by the female spawner. The redds are made up of clean gravel which has spaces for the eggs to be protected from predators. The eggs incubate over the winter (2-3 months) and then hatch as alevin.

:)Alevins have are hatched with a tiny yolk sac which is attached to the underside of the body. This sac gives the alevins their food for 1-2 months. The alevins will stay in the redd until spring when the yolk sac has disappeared.

:)When the alevin can no longer get nourishment from the yolk sac, they absorb it into their body and are now considered fry. The fry emerge from the gravel and begin feeding on small insects and plants.

:)Smolt are juvenile salmon and at this stage the salmon eat all the time. They continue to grow rapidly through this stage. As this stage ends the smolt move towards the ocean and they undergo a change which will allow them to live in saltwater

:)The adult salmon lives in the ocean for about 1-6 years. After the 1-6 year period the salmon start to migrate back to the stream they were spawned. Once the fish move into freshwater streams, they quit feeding and their bodies change in color and shape. For example a male salmon will develop a hook in their nose called a kype.







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Offline Quantumcat

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Re: How do fish reproduce?
« Reply #3 on: 28/06/2003 12:25:35 »
Very imformative, thanks Exie.

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Re: How do fish reproduce?
« Reply #3 on: 28/06/2003 12:25:35 »

 

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