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• 1. [Article] Easy Angling Oregon

  Abstract -- These rivers, lakes, ponds and streams have been selected with families and newcomers in mind. Besides offering a representative sampling of the state's angling and scenic variety, these locations: Are ...

  Citation × Citation Citation Abstract Copy Title: Easy Angling Oregon Abstract -- These rivers, lakes, ponds and streams have been selected with families and newcomers in mind. Besides offering a representative sampling of the state's angling and scenic variety, these locations: Are easily accessible by family car; Hold lots of fish on which to try your luck and sharpen your skills; Offer good odds of success using basic angling techniques; Have comfort facilities available (such as toilets, drinking water, picnic tables); and Offer easy-to-understand angling regulations. Easy Angling Oregon contains fishing opportunities from each of Oregon's six inland angling zones: Northwest, Southwest, Willamette, Central, Southeast and Northeast. These zones correspond to the geographic areas defined in the Oregon Sport Fishing Regulations. Within each zone you will find "Featured" and ''Also Recommended" locations. Title: Easy Angling Oregon Abstract -- These rivers, lakes, ponds and streams have been selected with families and newcomers in mind. Besides offering a representative sampling of the state's angling and scenic variety, these locations: Are easily accessible by family car; Hold lots of fish on which to try your luck and sharpen your skills; Offer good odds of success using basic angling techniques; Have comfort facilities available (such as toilets, drinking water, picnic tables); and Offer easy-to-understand angling regulations. Easy Angling Oregon contains fishing opportunities from each of Oregon's six inland angling zones: Northwest, Southwest, Willamette, Central, Southeast and Northeast. These zones correspond to the geographic areas defined in the Oregon Sport Fishing Regulations. Within each zone you will find "Featured" and ''Also Recommended" locations. Close

• 2. [Article] Mating Success of Alternative Male Phenotypes and Evidence for Frequency-Dependent Selection in Chinook Salmon, Oncorhynchus Tshawytscha - 2010

  Abstract -- As with other species, frequency-dependent selection during reproduction has long been proposed as an important mechanism in maintaining alternative male reproductive phenotypes in Pacific ...

  Citation × Citation Citation Abstract Copy Title: Mating Success of Alternative Male Phenotypes and Evidence for Frequency-Dependent Selection in Chinook Salmon, Oncorhynchus Tshawytscha - 2010 Abstract -- As with other species, frequency-dependent selection during reproduction has long been proposed as an important mechanism in maintaining alternative male reproductive phenotypes in Pacific salmon (Oncorhynchus spp.). Jack salmon mature one year earlier than the youngest females in a population and are much smaller than older ‘‘adult’’ males. We tested the hypothesis that mating success of both phenotypes is consistent with the frequency-dependent selection model. By holding male density constant and varying the frequency of adults and jacks in eight separate breeding groups, we found that adult male access to females, participation in spawning events, and adult-to-fry reproductive success increased with their decreasing frequency in a breeding group. Jacks exhibited the same pattern (increasing success with decreasing frequency), although the relationships were not as strong as for adults. Overall, jack and adult males mated with a similar number of females, but jacks sired only 20% of all offspring. Observational data suggested that adult males benefited from sperm precedence associated with their ability to court females and enter the nest first at the time of spawning. Our work provides the first experimental evidence of frequency-dependent selection during mating in the family Salmonidae. Lower Snake River Compensation Plan (LSRCP) ODFW- Eastern Oregon Fish Research (EOFR) Title: Mating Success of Alternative Male Phenotypes and Evidence for Frequency-Dependent Selection in Chinook Salmon, Oncorhynchus Tshawytscha - 2010 Abstract -- As with other species, frequency-dependent selection during reproduction has long been proposed as an important mechanism in maintaining alternative male reproductive phenotypes in Pacific salmon (Oncorhynchus spp.). Jack salmon mature one year earlier than the youngest females in a population and are much smaller than older ‘‘adult’’ males. We tested the hypothesis that mating success of both phenotypes is consistent with the frequency-dependent selection model. By holding male density constant and varying the frequency of adults and jacks in eight separate breeding groups, we found that adult male access to females, participation in spawning events, and adult-to-fry reproductive success increased with their decreasing frequency in a breeding group. Jacks exhibited the same pattern (increasing success with decreasing frequency), although the relationships were not as strong as for adults. Overall, jack and adult males mated with a similar number of females, but jacks sired only 20% of all offspring. Observational data suggested that adult males benefited from sperm precedence associated with their ability to court females and enter the nest first at the time of spawning. Our work provides the first experimental evidence of frequency-dependent selection during mating in the family Salmonidae. Lower Snake River Compensation Plan (LSRCP) ODFW- Eastern Oregon Fish Research (EOFR) Close