Jack salmon

Jacks are precotial male salmon that have spent one winter less in the ocean than the youngest females of a given species. Because they are younger, jack salmon are smaller than other age classes of conspecifics. Coho jacks return to spawn the same year they smolted and so are particularly small. Jack coloration can differ from that of older adults. Jacks are able to successfully sneak-spawn in spite of efforts by the female and occasionally the other males.

Coho Salmon jack hiding
A Coho Salmon a.k.a. Silver salmon (Oncorhynchus kisutch) jack or precotial male hiding below an alpha male.
Alaska Autumn Class Actinopterygii Coho Salmon Infraclass Teleostei Oncorhynchus kisutch Pacific salmon Phyllum Chordata Power Creek Salmonidae Salmoniformes Salmoninae Sea Sea internal correction lens Silver Salmon South Central Alaska Subclass Neopterygii Teleost United States Vertebrate jack jack salmon near Cordova precocial male precocious male underwater wild wild salmon
Jack salmon interest
A tiny Chinook Salmon a.k.a. King Salmon (Oncorhynchus tshawytscha) jack or precocial male observes a female probing the surface of a rock with her anal fin during redd excavation in Montana Creek near Talkeetna, Alaska.
Alaska Chinook Salmon Class Actinopterygii Infraclass Teleostei King Salmon Montana Creek Oncorhynchus tshawytscha Pacific salmon Phyllum Chordata Salmonidae Salmoniformes Salmoninae South Central Alaska South Central Alaska 1 Subclass Neopterygii Summer Susitna River Tributary Teleost United States Vertebrate fish behavior jack jack salmon near Talkeetna precocial male precocious male probing spawning behavior wild wild salmon
Jack salmon escape
A tiny Chinook Salmon a.k.a. King Salmon (Oncorhynchus tshawytscha) jack or precocial male evades being charged at by the alpha male as the female (at right edge of frame) excavates her redd in Montana Creek near Talkeetna, Alaska.
Alaska Chinook Salmon Class Actinopterygii Infraclass Teleostei King Salmon Montana Creek Oncorhynchus tshawytscha Pacific salmon Phyllum Chordata Salmonidae Salmoniformes Salmoninae South Central Alaska South Central Alaska 1 Subclass Neopterygii Summer Susitna River Tributary Teleost United States Vertebrate jack jack salmon near Talkeetna precocial male precocious male wild wild salmon
Coho Salmon in the actof spawning including a jack
A jack joins a Coho Salmon (Oncorhynchus kisutch) pair in the act of spawning.
Autumn Class Actinopterygii Dolly Varden Dolly Varden Char Dolly Varden Charr Dolly Varden Charr southern form Infraclass Teleostei Phyllum Chordata Salmonidae Salmoniformes Salmoninae Salvelinus malma Salvelinus malma lordi Seacam underwater housing Subclass Neopterygii Teleost Vertebrate underwater wild wild salmon
Chinook Salmon jack
A Chinook Salmon (Oncorhynchus tshawytscha) jack is positioned in a stream next to a redd.
Chinook Salmon Class Actinopterygii Infraclass Teleostei King Salmon Oncorhynchus tshawytscha Pacific salmon Phyllum Chordata Salmonidae Salmoniformes Salmoninae Seacam underwater housing Subclass Neopterygii Summer Teleost Vertebrate jack jack salmon precocial male precocious male underwater wild wild salmon
Two jacks about to join a pair of spawning Coho Salmon spawning pair
Two jacks about to join a pair of spawning Coho Salmon (Oncorhynchus kisutch) spawning pair. Aspect Ratio = 4:5.
Autumn Class Actinopterygii Coho Salmon Infraclass Teleostei Oncorhynchus kisutch Pacific salmon Phyllum Chordata Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon Subclass Neopterygii Teleost Vertebrate jack jack salmon precocial male precocious male underwater wild wild salmon
Coho Salmon female with a jack
Female Coho Salmon a.k.a. Silver salmon (Oncorhynchus kisutch) being courted by a jack in an Alaska, USA stream during the autumn.
Autumn Class Actinopterygii Coho Salmon Infraclass Teleostei Oncorhynchus kisutch Pacific salmon Phyllum Chordata Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon Subclass Neopterygii Teleost Vertebrate fish behavior jack jack salmon nature precocial male precocious male probing spawning behavior underwater wild wild salmon
Coho Salmon female with a jack
Coho Salmon (Oncorhynchus kisutch) female with a jack. Aspect ratio = 2:3.
Autumn Class Actinopterygii Coho Salmon Infraclass Teleostei Oncorhynchus kisutch Pacific salmon Phyllum Chordata Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon Subclass Neopterygii Teleost Vertebrate jack jack salmon precocial male precocious male underwater wild wild salmon
Coho Salmon after spawning with a jack
Coho Salmon (Oncorhynchus kisutch) after spawning with a jack. Aspect ratio = 2:3.
Autumn Class Actinopterygii Coho Salmon Infraclass Teleostei Oncorhynchus kisutch Pacific salmon Phyllum Chordata Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon Subclass Neopterygii Teleost Vertebrate fish behavior jack jack salmon precocial male precocious male spawning spawning act spawning behavior underwater wild wild salmon
Coho Salmon commencing to spawn with a jack
Coho Salmon a.k.a. Silver Silver (Oncorhynchus kisutch) commencing to spawn about to be joined by a jack in an Alaska, USA stream during the autumn.
Autumn Class Actinopterygii Coho Salmon Infraclass Teleostei Oncorhynchus kisutch Pacific salmon Phyllum Chordata Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon Subclass Neopterygii Teleost Vertebrate fish behavior jack jack salmon nature precocial male precocious male probing spawning spawning act spawning behavior underwater wild wild salmon
Coho Salmon female with a jack
Coho Salmon (Oncorhynchus kisutch) female with a jack. Aspect ratio = 2:3.
Autumn Class Actinopterygii Coho Salmon Infraclass Teleostei Oncorhynchus kisutch Pacific salmon Phyllum Chordata Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon Subclass Neopterygii Teleost Vertebrate jack jack salmon precocial male precocious male underwater wild wild salmon
Courting Coho Salmon and a Sockeye Salmon jack
A Sockeye Salmon jack emerges from the fracas that often ensues during salmon courtship, in this case another species, Coho Salmon. Aspect Ratio = 1:2.
Autumn Class Actinopterygii Coho Salmon Infraclass Teleostei Oncorhynchus kisutch Pacific salmon Phyllum Chordata Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon Subclass Neopterygii Teleost Vertebrate excavating redd jack jack salmon precocial male precocious male underwater wild wild salmon
Coho Salmon jack
Coho Salmon (Oncorhynchus kisutch) jack.
Autumn Class Actinopterygii Coho Salmon Infraclass Teleostei Oncorhynchus kisutch Pacific salmon Phyllum Chordata Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon Subclass Neopterygii Teleost Vertebrate jack jack salmon precocial male precocious male underwater wild wild salmon
Coho Salmon female with a jack
Female Coho Salmon a.k.a. Silver salmon (Oncorhynchus kisutch) being courted by a jack in an Alaska, USA stream during the autumn.
Autumn Class Actinopterygii Coho Salmon Infraclass Teleostei Oncorhynchus kisutch Pacific salmon Phyllum Chordata Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon Subclass Neopterygii Teleost Vertebrate covering redd fish behavior jack jack salmon nature precocial male precocious male salmonography.com spawning spawning act spawning behavior underwater wild wild salmon
Sockeye Salmon female attacking a jack.
Sockeye Salmon (Oncorhynchus nerka) female attacking a jack. Aspect Ratio = 2:3.
Class Actinopterygii Infraclass Teleostei Oncorhynchus nerka Pacific salmon Phyllum Chordata Red Salmon Salmonidae Salmoniformes Salmoninae Seacam underwater housing Sockeye Salmon Subclass Neopterygii Summer Teleost Vertebrate aggression fighting fish behavior underwater wild wild salmon
Spawning Coho Salmon including a jack
Coho Salmon (Oncorhynchus kisutch) including a jack commencing to spawn. Aspect Ratio = 1:2.
Alaska Autumn Class Actinopterygii Coho Salmon Infraclass Teleostei Oncorhynchus kisutch Pacific salmon Phyllum Chordata Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon South Central Alaska 2 Subclass Neopterygii Teleost United States Vertebrate underwater wild wild salmon
Jack among other Coho Salmon
Coho Salmon (Oncorhynchus kisutch) jack or precocious male among other coho on their spawning migration in a tributary of Eyak Lake, Alaska. Aspect Ratio = 2:3.
Alaska Autumn Class Actinopterygii Coho Salmon Infraclass Teleostei Oncorhynchus kisutch Pacific salmon Phyllum Chordata Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon South Central Alaska 2 Subclass Neopterygii Teleost United States Vertebrate fish behavior jack jack salmon precocial male precocious male salmonography.com spawning migration underwater wild wild salmon
A jack sneaking alongside a normal sized male Sockeye Salmon
A jack sneaking alongside a normal sized male Sockeye Salmon (Oncorhynchus nerka). Aspect Ratio = 4:5.
Alaska Class Actinopterygii Infraclass Teleostei Oncorhynchus nerka Pacific salmon Phyllum Chordata Red Salmon Salmonidae Salmoniformes Salmoninae Seacam underwater housing Sockeye Salmon South Central Alaska 2 Subclass Neopterygii Teleost United States Vertebrate jack jack salmon precocial male precocious male salmonography.com underwater wild wild salmon
Male and two jack Coho Salmon
Coho Salmon (Oncorhynchus kisutch) males during their spawning migration; the two smaller individuals are jacks or precocious males. Aspect ratio = 2:3.
Alaska Class Actinopterygii Coho Salmon Infraclass Teleostei Oncorhynchus kisutch Pacific salmon Phyllum Chordata Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon South Central Alaska 2 Subclass Neopterygii Teleost United States Vertebrate jack jack salmon precocial male precocious male underwater wild wild salmon