Breeding Success Of Four Male Life History Types In Spring Chinook Salmon Spawning Under Quasi-Natural Conditions

Spring Chinook Spawning Communities Are Generally Thought Of As Assemblages Of Large Anadromous Fish

However, A Variety Of Alternative Male Life History Types Occur On Spawning Grounds

And Their Abundance May Increase Due To Artificial Culture

What Genetic Effects Might Enhanced Numbers Of Early Maturing Males Have On Wild Spring Chinook Populations?

The Artificial Stream At Cle Elum

Types Of Fish In The Test Groups

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Prior To Placement In The Artificial Stream Each Fish Was:

And, A Small Bit Of Fin Material Was Removed For Later DNA Extraction

The Fish Were Released Into The Artificial Stream & Spawned Under Quasi-Natural Conditions

Fish No.s & Types Placed Into The Artificial Stream

All Fry Produced From The Artificial Stream Were Trapped & Counted

Fry Production

Calculating Male Breeding Success

Results Were Examined In Two Ways

Mean Fork Lengths Of The Male Life History Types

Body Wt vs. Breeding Success In Large Anadromous Males

Breeding Success Vs. Fork Length In Precocious Males

Effect Of Tertiary Sex Ratio On Individual Male Breeding Success

Mate Number & Breeding Success By Male Life History Type

Fry Per Mate By Male Life History Type

Mean Mate Number By Life History Type

Mean Individual Breeding Success By Male Life History Type

Relative Breeding Success Of The Life History Types

Tertiary Sex Ratios Vs. Progeny Paternity

% Male Life History Type Vs. Progeny Paternity

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