Jack salmon

Jacks are precocial 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.

Lurking jack
A Sockeye Salmon (Oncorhynchus nerka) jack lurking near the tail of an alpha male. In the background, the female they want to spawn with is visible above the alpha male's head.
25Mile Creek Actinopterygii Alaska Animal Biology Chordata Class Actinopterygii Copper River Delta Ecology Infraclass Teleostei Neopterygii Oncorhynchus nerka Pacific salmon Phylum Chordata Red Salmon Salmonidae Salmoniformes Salmoninae Sockeye Salmon South Central Alaska Subclass Neopterygii Teleost Teleostei United States Vertebrate anadromous anadromy biological chordate diadromous diadromy fresh water freshwater jack jack salmon living lotic migratory organism precocial male precocious male semelparity semelparous stream summer under fresh water underwater
Coho Salmon in the act of spawning
Coho Salmon (Oncorhynchus kisutch) in the act of spawning. The male entering the fray from the top is the alpha male changing position after the two sneaker males barged in. The female is to his left. The little male with the spots in the frame on the left is a precocial male a.k.a. jack salmon.
Actinopterygii Alaska Animal Autumn Biology Chordata Class Actinopterygii Coho Salmon Ecology Infraclass Teleostei Neopterygii Oncorhynchus kisutch Pacific salmon Phylum Chordata Power Creek Reproductive behavior Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon South Central Alaska Subclass Neopterygii Teleost Teleostei United States Vertebrate alpha male anadromous anadromy biological biosphere chordate courtship diadromous diadromy fresh water freshwater in situ jack jack salmon living lotic male behavior migratory naturalworld nature near Cordova organism precocial male precocious male semelparity semelparous spawning spawning act spawning behavior stream under fresh water underwater underwaterphoto wild
Coho Salmon jack
A precotial male a.k.a. jack Coho Salmon ((Oncorhynchus kisutch) sneaks under a partially-spawned female hoping to spawn with her.
Actinopterygii Alaska Animal Autumn Biology Chordata Class Actinopterygii Coho Salmon Ecology Infraclass Teleostei Neopterygii Oncorhynchus kisutch Pacific salmon Phylum Chordata Power Creek Salmonidae Salmoniformes Salmoninae Sea Sea internal correction lens Seacam underwater housing Silver Salmon South Central Alaska Subclass Neopterygii Teleost Teleostei United States Vertebrate biological biosphere chordate in situ jack jack salmon living naturalworld nature near Cordova organism precocial male precocious male underwater underwaterphoto wild
Coho Salmon jack hiding
A Coho Salmon a.k.a. Silver salmon (Oncorhynchus kisutch) jack or precocial male hiding below an alpha male.
Actinopterygii Alaska Alaska wild salmon Animal Autumn Biology Chordata Class Actinopterygii Coho Salmon Ecology Infraclass Teleostei Neopterygii Oncorhynchus kisutch Pacific salmon Phylum Chordata Power Creek Salmonidae Salmoniformes Salmoninae Sea Sea internal correction lens Seacam underwater housing Silver Salmon South Central Alaska Subclass Neopterygii Teleost Teleostei United States Vertebrate anadromous anadromy biological biosphere chordate diadromous diadromy fresh water freshwater in situ jack jack salmon living lotic migratory naturalworld nature near Cordova organism precocial male precocious male semelparity semelparous stream under fresh water underwater underwaterphoto wild wild salmon
Jack Chinook Salmon
A Chinook Salmon (Oncorhynchus tshawytshca) jack flanks (foreground of image) a redd following a spawning as Rainbow Trout (O. mykiss) predate the eggs and other males stand by as the female covers in Montana Creek, near Talkeetna, Alaska.
Actinopterygii Alaska Animal Biology Chinook Salmon Chordata Class Actinopterygii Ecology Infraclass Teleostei King Salmon Montana Creek Neopterygii Oncorhynchus mykiss Oncorhynchus tshawytscha Pacific salmon Pacific trout Phylum Chordata Rainbow Trout Salmonidae Salmoniformes Salmoninae Seacam underwater housing South Central Alaska Subclass Neopterygii Summer Susitna River Tributary Teleost Teleostei United States Vertebrate biological biosphere chordate in situ jack jack salmon living naturalworld nature near Talkeetna organism precocial male precocious male underwater underwaterphoto wild wild salmon www.salmonography.com
Jack observes female Chinook Salmon
This tiny Chinook Salmon (Oncorhynchus tshawytscha) jack observes a female probing a rock with her anal fin during the excavation of her redd that he desires to spawn in.
Actinopterygii Alaska Animal Biology Chinook Salmon Chordata Class Actinopterygii Ecology Infraclass Teleostei King Salmon Montana Creek Neopterygii Oncorhynchus tshawytscha Pacific salmon Phylum Chordata Reproductive behavior Salmonidae Salmoniformes Salmoninae Seacam underwater housing South Central Alaska Subclass Neopterygii Susitna River Tributary Teleost Teleostei United States Vertebrate biological biosphere chordate courtship in situ jack jack salmon living naturalworld nature near Talkeetna organism precocial male precocious male probing spawning behavior summer underwater underwaterphoto 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.
Actinopterygii Alaska Alaska wild salmon Animal Biology Chinook Salmon Chordata Class Actinopterygii Ecology Infraclass Teleostei King Salmon Montana Creek Neopterygii Oncorhynchus tshawytscha Pacific salmon Phylum Chordata Reproductive behavior Salmonidae Salmoniformes Salmoninae Seacam underwater housing South Central Alaska South Central Alaska 1 Subclass Neopterygii Summer Susitna River Tributary Teleost Teleostei United States Vertebrate anadromous anadromy biological biosphere chordate courtship diadromous diadromy fresh water freshwater in situ jack jack salmon living lotic migratory naturalworld nature near Talkeetna organism precocial male precocious male probing semelparity semelparous spawning behavior stream under fresh water underwater underwaterphoto 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.
Actinopterygii Alaska Alaska wild salmon Animal Biology Chinook Salmon Chordata Class Actinopterygii Ecology Infraclass Teleostei King Salmon Montana Creek Neopterygii Oncorhynchus tshawytscha Pacific salmon Phylum Chordata Salmonidae Salmoniformes Salmoninae Seacam underwater housing South Central Alaska South Central Alaska 1 Subclass Neopterygii Summer Susitna River Tributary Teleost Teleostei United States Vertebrate anadromous anadromy biological biosphere chordate diadromous diadromy fresh water freshwater in situ jack jack salmon living lotic migratory naturalworld nature near Talkeetna organism precocial male precocious male semelparity semelparous stream under fresh water underwater underwaterphoto wild wild salmon
A jack tags along as a female Chinook Salmon covers her redd
A jack tags along as a female Chinook Salmon (Oncorhynchus tshawytscha) covers her redd after spawning in Montana Creek near Talkeetna, Alaska.
Actinopterygii Alaska Alaska wild salmon Animal Biology Chinook Salmon Chordata Class Actinopterygii Ecology Infraclass Teleostei King Salmon Montana Creek Neopterygii Oncorhynchus tshawytscha Pacific salmon Phylum Chordata Reproductive behavior Salmonidae Salmoniformes Salmoninae Seacam underwater housing South Central Alaska Subclass Neopterygii Summer Susitna River Tributary Teleost Teleostei United States Vertebrate anadromous anadromy biological biosphere chordate courtship covering redd diadromous diadromy fresh water freshwater in situ jack jack salmon living lotic migratory naturalworld nature near Talkeetna organism photographed under water precocial male precocious male semelparity semelparous spawning behavior stream topside under fresh water underwater underwaterphoto wild wild salmon
Coho Salmon in the act of spawning including a jack
A jack (left side of frame) joins a pair of Coho Salmon (Oncorhynchus kisutch) in the act of spawning.
Actinopterygii Alaska Alaska wild salmon Animal Autumn Biology Chordata Class Actinopterygii Coho Salmon Dolly Varden Dolly Varden Char Dolly Varden Charr Dolly Varden Charr southern form Ecology Infraclass Teleostei Neopterygii Oncorhynchus kisutch Pacific salmon Phylum Chordata Salmonidae Salmoniformes Salmoninae Salvelinus malma Salvelinus malma lordi Seacam underwater housing Silver Salmon South Central Alaska Subclass Neopterygii Teleost Teleostei United States Vertebrate anadromous anadromous fish anadromy biological biosphere chordate diadromous diadromy fresh water freshwater in situ living lotic migratory naturalworld organism semelparity semelparous stream under fresh water underwater wild wild salmon
Chinook Salmon jack
A Chinook Salmon (Oncorhynchus tshawytscha) jack is positioned in a stream next to a redd.
Actinopterygii Alaska Alaska wild salmon Animal Biology Chinook Salmon Chordata Class Actinopterygii Ecology Infraclass Teleostei King Salmon Neopterygii Oncorhynchus tshawytscha Pacific salmon Phylum Chordata Salmonidae Salmoniformes Salmoninae Seacam underwater housing South Central Alaska Subclass Neopterygii Summer Teleost Teleostei United States Vertebrate anadromous anadromy biological biosphere chordate diadromous diadromy fresh water freshwater in situ jack jack salmon living lotic migratory naturalworld nature organism photographed under water precocial male precocious male semelparity semelparous stream under fresh water underwater underwaterphoto wild wild salmon
Chinook Salmon jack
A Chinook Salmon (Oncorhynchus tshawytscha) jack is positioned in a stream next to a redd.
Actinopterygii Alaska wild salmon Animal Biology Chinook Salmon Chordata Class Actinopterygii Ecology Infraclass Teleostei King Salmon Neopterygii Oncorhynchus tshawytscha Pacific salmon Phylum Chordata Salmonidae Salmoniformes Salmoninae Seacam underwater housing Subclass Neopterygii Summer Teleost Teleostei Vertebrate anadromous anadromy biological biosphere chordate diadromous diadromy fresh water freshwater in situ jack jack salmon living lotic migratory naturalworld nature organism photographed under water precocial male precocious male semelparity semelparous stream under fresh water underwater underwaterphoto wild wild salmon
Chinook Salmon jack
A Chinook Salmon (Oncorhynchus tshawytscha) jack is positioned in a stream next to a redd.
Actinopterygii Alaska wild salmon Animal Biology Chinook Salmon Chordata Class Actinopterygii Ecology Infraclass Teleostei King Salmon Neopterygii Oncorhynchus tshawytscha Pacific salmon Phylum Chordata Reproductive behavior Salmonidae Salmoniformes Salmoninae Seacam underwater housing Subclass Neopterygii Summer Teleost Teleostei Vertebrate anadromous anadromy biological biosphere chordate courtship diadromous diadromy digging excavating fresh water freshwater in situ jack jack salmon living lotic migratory naturalworld nature organism photographed under water precocial male precocious male semelparity semelparous spawning behavior stream under fresh water underwater underwaterphoto wild wild salmon
Chinook Salmon jack
A Chinook Salmon (Oncorhynchus tshawytscha) jack is positioned in a stream next to a redd.
Actinopterygii Alaska wild salmon Animal Biology Chinook Salmon Chordata Class Actinopterygii Ecology Infraclass Teleostei King Salmon Neopterygii Oncorhynchus tshawytscha Pacific salmon Phylum Chordata Salmonidae Salmoniformes Salmoninae Seacam underwater housing Subclass Neopterygii Summer Teleost Teleostei Vertebrate anadromous anadromy biological biosphere chordate diadromous diadromy fresh water freshwater in situ jack jack salmon living lotic migratory naturalworld nature organism photographed under water precocial male precocious male semelparity semelparous stream under fresh water underwater underwaterphoto wild wild salmon
False spawning
Multiple male Coho Salmon (Oncorhynchus kisutch) piled up next to a nearly completed redd pocket following a false spawning. The female has moved off to the side (left side of frame) while the alpha male is downstream (in background) having left the fracas. The heavely spotted fish located above and upstream of the pile-up is a jack.
Actinopterygii Alaska Animal Autumn Biology Chordata Class Actinopterygii Coho Salmon Ecology Infraclass Teleostei Neopterygii Oncorhynchus kisutch Pacific salmon Phylum Chordata Reproductive behavior Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon South Central Alaska Subclass Neopterygii Teleost Teleostei United States Vertebrate anadromous anadromy biological biosphere chordate courtship diadromous diadromy false spawning fresh water freshwater in situ jack jack salmon living lotic migratory naturalworld nature organism precocial male precocious male semelparity semelparous spawning behavior stream under fresh water underwater underwaterphoto wild
False spawning
A female Coho Salmon (Oncorhynchus kisutch) exits her redd as three sneaker males including a jack (nearest fish, just entering the fray) commence to false spawn. The alpha male is poking over the female's caudal peduncle from her right side in background of shot.
Actinopterygii Alaska Animal Autumn Biology Chordata Class Actinopterygii Coho Salmon Ecology Infraclass Teleostei Neopterygii Oncorhynchus kisutch Pacific salmon Phylum Chordata Reproductive behavior Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon South Central Alaska Subclass Neopterygii Teleost Teleostei United States Vertebrate alpha male anadromous anadromy biological biosphere chordate courtship diadromous diadromy false spawning fresh water freshwater in situ jack jack salmon living lotic male behavior migratory naturalworld nature organism precocial male precocious male semelparity semelparous spawning behavior stream under fresh water underwater underwaterphoto wild
Hopeful
In anticipation of spawning, a jack Coho Salmon (Oncorhynchus kisutch) positions himself in a redd near to where the adjacent female will release her eggs.
Actinopterygii Animal Biology Chordata Class Actinopterygii Coho Salmon Ecology Infraclass Teleostei Neopterygii Oncorhynchus kisutch Pacific salmon Phylum Chordata Reproductive behavior Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon Subclass Neopterygii Teleost Teleostei Vertebrate biological biosphere breeding colors chordate courtship in situ jack jack salmon living naturalworld nature nuptial coloration organism precocial male precocious male probing spawning behavior underwater underwaterphoto wild
Two jacks
Two jacks about to join a pair of spawning Coho Salmon (Oncorhynchus kisutch). Aspect Ratio = 4:3.
Actinopterygii Alaska Alaska wild salmon Animal Autumn Biology Chordata Class Actinopterygii Coho Salmon Ecology Infraclass Teleostei Neopterygii Oncorhynchus kisutch Pacific salmon Phylum Chordata Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon South Central Alaska Subclass Neopterygii Teleost Teleostei United States Vertebrate anadromous anadromous fish anadromy biological biosphere chordate diadromous diadromy fresh water freshwater in situ living lotic migratory naturalworld nature organism semelparity semelparous stream under fresh water underwater underwaterphoto wild wild salmon
Three jacks
Three jacks attempting to join a Coho Salmon (Oncorhynchus kisutch) spawning pair. Aspect Ratio = 4:3.
Actinopterygii Animal Autumn Biology Chordata Class Actinopterygii Coho Salmon Ecology Infraclass Teleostei Neopterygii Oncorhynchus kisutch Pacific salmon Phylum Chordata Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon Subclass Neopterygii Teleost Teleostei Vertebrate anadromous anadromy biological biosphere chordate diadromous diadromy fresh water freshwater in situ living lotic migratory naturalworld nature organism semelparity semelparous stream under fresh water underwater underwaterphoto wild
Sockeye Salmon jack
Sockeye Salmon (Oncorhynchus nerka) jack that was encroaching on a Coho Salmon (O. kisutch) redd being attacked by the alpha male while female moved to a safe distance downstream.
Actinopterygii Animal Autumn Biology Chordata Class Actinopterygii Coho Salmon Ecology Infraclass Teleostei Neopterygii Oncorhynchus kisutch Oncorhynchus nerka Pacific salmon Phylum Chordata Red Salmon Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon Sockeye Salmon Subclass Neopterygii Teleost Teleostei Vertebrate aggression anadromous anadromy biological biosphere chordate diadromous diadromy fighting fresh water freshwater in situ jack jack salmon living lotic migratory naturalworld nature organism precocial male precocious male semelparity semelparous stream under fresh water underwater underwaterphoto wild
Sockeye Salmon spawning migration
Sockeye Salmon (Oncorhynchus nerka) nearing their spawning grounds in a Copper River Delta, Alaska stream showing variation in breeding colors a.k.a nuptial coloration. The small mostly green-colored salmon with a horizontal red bar on the left side of this image is a jack salmon or precocial male.
Actinopterygii Alaska Animal Biology Chordata Class Actinopterygii Copper River Delta Ecology Infraclass Teleostei Neopterygii Oncorhynchus nerka Pacific salmon Phylum Chordata Red Salmon Reproductive behavior Saddlebag Creek Salmonidae Salmoniformes Salmoninae Seacam underwater housing Sockeye Salmon South Central Alaska Subclass Neopterygii Summer Teleost Teleostei United States Vertebrate anadromous anadromy biological biosphere breeding colors chordate courtship diadromous diadromy fresh water freshwater in situ jack jack salmon living lotic migratory naturalworld nature nuptial coloration organism precocial male precocious male scale resorption semelparity semelparous spawning migration staging stream under fresh water underwater underwaterphoto wild
Three jacks
Three Sockeye salmon (Oncorhynchus nerka) jacks appear to be leading a procession of conspecifics during their spawning migration while another jack passing a normal male receives a gaping threat.
Actinopterygii Alaska Animal Biology Carangidae Chordata Class Actinopterygii Copper River Delta Ecology Infraclass Teleostei jack Neopterygii Oncorhynchus nerka Pacific salmon Perciformes Percoidei Phylum Chordata Red Salmon Saddlebag Creek Salmonidae Salmoniformes Salmoninae Seacam underwater housing Sockeye Salmon South Central Alaska Subclass Neopterygii Summer Teleost Teleostei United States Vertebrate anadromous anadromy biological biosphere chordate diadromous diadromy fresh water freshwater in situ jack salmon living lotic migratory naturalworld nature organism precocial male precocious male semelparity semelparous staging stream under fresh water underwater underwaterphoto wild
Sneaker courtship
A probable jack, this sneaker Sockeye Salmon (Oncorhynchus nerka) male courts a female while the alpha male is chasing away another male.
Actinopterygii Animal Biology Chordata Class Actinopterygii Ecology Infraclass Teleostei Neopterygii Oncorhynchus nerka Pacific salmon Phylum Chordata Red Salmon Reproductive behavior Salmonidae Salmoniformes Salmoninae Seacam underwater housing Sockeye Salmon Subclass Neopterygii summer Teleost Teleostei Vertebrate biological biosphere chordate courting pair courtship in situ jack jack salmon living male behavior naturalworld nature organism precocial male precocious male quivering sneaker male spawning behavior underwater underwaterphoto wild
Jack and female Sockeye Salmon
A jack Sockeye Salmon (Oncorhynchus nerka) approaches a female with intentions of spawning with her.
Actinopterygii Alaska Animal Biology Carangidae Chordata Class Actinopterygii Ecology Infraclass Teleostei jack Neopterygii Oncorhynchus nerka Pacific salmon Perciformes Percoidei Phylum Chordata Red Salmon Salmonidae Salmoniformes Salmoninae Seacam underwater housing Sockeye Salmon South Central Alaska Subclass Neopterygii Summer Teleost Teleostei United States Vertebrate anadromous anadromy biological biosphere chordate diadromous diadromy fresh water freshwater in situ jack salmon living lotic migratory naturalworld nature organism precocial male precocious male semelparity semelparous stream under fresh water underwater underwaterphoto wild
Jack ejection
A Sockeye salmon (Oncorhynchus nerka) jack swims away from a spawning event after being ejected by the alpha male.
Actinopterygii Alaska Animal Biology Chordata Class Actinopterygii Ecology Infraclass Teleostei Neopterygii Oncorhynchus nerka Pacific salmon Phylum Chordata Red Salmon Salmonidae Salmoniformes Salmoninae Seacam underwater housing Sockeye Salmon South Central Alaska Subclass Neopterygii Summer Teleost Teleostei United States Vertebrate anadromous anadromy biological biosphere chordate diadromous diadromy fresh water freshwater in situ jack jack salmon living lotic migratory naturalworld nature organism precocial male precocious male semelparity semelparous stream under fresh water underwater underwaterphoto wild
Jack rebuffed
A Sockeye Salmon (Oncorhynchus nerka) jack approaching a female to spawn with gets rebuffed by the alpha male who is using an aggressive gape display.
Actinopterygii Alaska Animal Biology Carangidae Chordata Class Actinopterygii Ecology Infraclass Teleostei jack Neopterygii Oncorhynchus nerka Pacific salmon Perciformes Percoidei Phylum Chordata Red Salmon Salmonidae Salmoniformes Salmoninae Seacam underwater housing Sockeye Salmon South Central Alaska Subclass Neopterygii Summer Teleost Teleostei United States Vertebrate anadromous anadromy biological biosphere chordate diadromous diadromy fresh water freshwater in situ jack salmon living lotic migratory naturalworld nature organism precocial male precocious male semelparity semelparous stream under fresh water underwater underwaterphoto wild
Sockeye Salmon spawning
Sockeye Salmon (Oncorhynchus nerka) in the act of spawning. The tiny salmon on the left side of the frame is a precocial male a.k.a. jack salmon. He is also attempting to contribute to the gene pool.
Actinopterygii Alaska Animal Biology Chordata Class Actinopterygii Ecology Infraclass Teleostei Neopterygii Oncorhynchus nerka Pacific salmon Phylum Chordata Red Salmon Reproductive behavior Salmonidae Salmoniformes Salmoninae Seacam underwater housing Sockeye Salmon South Central Alaska Subclass Neopterygii summer Teleost Teleostei United States Vertebrate anadromous anadromy biological biosphere chordate courtship diadromous diadromy fresh water freshwater in situ jack jack salmon living lotic migratory naturalworld nature organism precocial male precocious male semelparity semelparous spawning spawning act spawning behavior stream under fresh water underwater underwaterphoto wild
Sockeye Salmon spawning
Sockeye Salmon (Oncorhynchus nerka) in the act of spawning. The tiny salmon on the left side of the frame is a precotial male a.k.a. jack salmon. He is also attempting to contribute to the gene pool.
Actinopterygii Alaska Animal Biology Chordata Class Actinopterygii Ecology Infraclass Teleostei Neopterygii Oncorhynchus nerka Pacific salmon Phylum Chordata Red Salmon Reproductive behavior Salmonidae Salmoniformes Salmoninae Seacam underwater housing Sockeye Salmon South Central Alaska Subclass Neopterygii summer Teleost Teleostei United States Vertebrate anadromous anadromy biological biosphere chordate courtship diadromous diadromy fresh water freshwater in situ jack jack salmon living lotic migratory naturalworld nature organism precocial male precocious male semelparity semelparous spawning spawning act spawning behavior stream under fresh water underwater underwaterphoto wild
Male Sockeye Salmon spawning morphs
A small jack comes alongside a normal sized male Sockeye Salmon (Oncorhynchus nerka).
Actinopterygii Alaska Animal Biology Chordata Class Actinopterygii Ecology Infraclass Teleostei Neopterygii Oncorhynchus nerka Pacific salmon Phylum Chordata Red Salmon Salmonidae Salmoniformes Salmoninae Seacam underwater housing Sockeye Salmon South Central Alaska Subclass Neopterygii Teleost Teleostei United States Vertebrate anadromous anadromy biological biosphere chordate diadromous diadromy fresh water freshwater in situ jack jack salmon living lotic migratory naturalworld nature organism precocial male precocious male semelparity semelparous stream under fresh water underwater underwaterphoto wild
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.
Actinopterygii Alaska Alaska wild salmon Animal Autumn Biology Chordata Class Actinopterygii Coho Salmon Ecology Infraclass Teleostei Neopterygii Oncorhynchus kisutch Pacific salmon Phylum Chordata Reproductive behavior Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon South Central Alaska Subclass Neopterygii Teleost Teleostei United States Vertebrate anadromous anadromy biological biosphere chordate courtship diadromous diadromy fresh water freshwater in situ jack jack salmon living lotic migratory naturalworld nature organism precocial male precocious male probing semelparity semelparous spawning behavior stream under fresh water underwater underwaterphoto wild wild salmon
Coho Salmon female with a jack
Coho Salmon (Oncorhynchus kisutch) female with a jack. Aspect ratio = 2:3.
Actinopterygii Alaska Alaska wild salmon Animal Autumn Biology Chordata Class Actinopterygii Coho Salmon Ecology Infraclass Teleostei Neopterygii Oncorhynchus kisutch Pacific salmon Phylum Chordata Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon South Central Alaska Subclass Neopterygii Teleost Teleostei United States Vertebrate anadromous anadromy biological biosphere chordate diadromous diadromy fresh water freshwater in situ jack jack salmon living lotic migratory naturalworld nature organism precocial male precocious male semelparity semelparous stream under fresh water underwater underwaterphoto wild wild salmon
Coho Salmon after spawning with a jack
Coho Salmon (Oncorhynchus kisutch) after spawning with a jack. Aspect ratio = 2:3.
Actinopterygii Alaska Alaska wild salmon Animal Autumn Biology Chordata Class Actinopterygii Coho Salmon Ecology Infraclass Teleostei Neopterygii Oncorhynchus kisutch Pacific salmon Phylum Chordata Reproductive behavior Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon South Central Alaska Subclass Neopterygii Teleost Teleostei United States Vertebrate anadromous anadromy biological biosphere chordate courtship diadromous diadromy fresh water freshwater in situ jack jack salmon living lotic migratory naturalworld nature organism precocial male precocious male semelparity semelparous spawning spawning act spawning behavior stream under fresh water underwater underwaterphoto 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.
Actinopterygii Alaska Alaska wild salmon Animal Autumn Biology Chordata Class Actinopterygii Coho Salmon Ecology Infraclass Teleostei Neopterygii Oncorhynchus kisutch Pacific salmon Phylum Chordata Reproductive behavior Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon South Central Alaska Subclass Neopterygii Teleost Teleostei United States Vertebrate anadromous anadromy biological biosphere chordate courtship diadromous diadromy fresh water freshwater in situ jack jack salmon living lotic migratory naturalworld nature organism precocial male precocious male probing semelparity semelparous spawning spawning act spawning behavior stream under fresh water underwater underwaterphoto wild wild salmon
Coho Salmon female with a jack
Coho Salmon (Oncorhynchus kisutch) female with a jack. Aspect ratio = 2:3.
Actinopterygii Alaska Alaska wild salmon Animal Autumn Biology Chordata Class Actinopterygii Coho Salmon Ecology Infraclass Teleostei Neopterygii Oncorhynchus kisutch Pacific salmon Phylum Chordata Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon South Central Alaska Subclass Neopterygii Teleost Teleostei United States Vertebrate anadromous anadromy biological biosphere chordate diadromous diadromy fresh water freshwater in situ jack jack salmon living lotic migratory naturalworld nature organism precocial male precocious male semelparity semelparous stream under fresh water underwater underwaterphoto 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.
Actinopterygii Alaska Alaska wild salmon Animal Autumn Biology Chordata Class Actinopterygii Coho Salmon Ecology Infraclass Teleostei Neopterygii Oncorhynchus kisutch Pacific salmon Phylum Chordata Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon South Central Alaska Subclass Neopterygii Teleost Teleostei United States Vertebrate anadromous anadromy biological biosphere chordate diadromous diadromy excavating redd fresh water freshwater in situ jack jack salmon living lotic migratory naturalworld nature organism precocial male precocious male semelparity semelparous stream under fresh water underwater underwaterphoto wild wild salmon
Coho Salmon jack
Coho Salmon (Oncorhynchus kisutch) jack.
Actinopterygii Alaska Alaska wild salmon Animal Autumn Biology Chordata Class Actinopterygii Coho Salmon Ecology Infraclass Teleostei Neopterygii Oncorhynchus kisutch Pacific salmon Phylum Chordata Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon South Central Alaska Subclass Neopterygii Teleost Teleostei United States Vertebrate anadromous anadromy biological biosphere chordate diadromous diadromy fresh water freshwater in situ jack jack salmon living lotic migratory naturalworld nature organism precocial male precocious male semelparity semelparous stream under fresh water underwater underwaterphoto 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.
Actinopterygii Alaska Alaska wild salmon Animal Autumn Biology Chordata Class Actinopterygii Coho Salmon Ecology Infraclass Teleostei Neopterygii Oncorhynchus kisutch Pacific salmon Phylum Chordata Reproductive behavior Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon South Central Alaska Subclass Neopterygii Teleost Teleostei United States Vertebrate anadromous anadromy biological biosphere chordate courtship covering redd diadromous diadromy fresh water freshwater in situ jack jack salmon living lotic migratory naturalworld nature organism precocial male precocious male salmonography.com semelparity semelparous spawning spawning act spawning behavior stream under fresh water underwater underwaterphoto wild wild salmon
Sockeye Salmon female attacking a jack.
Sockeye Salmon (Oncorhynchus nerka) female attacking a jack. Aspect Ratio = 2:3.
Actinopterygii Alaska Alaska wild salmon Animal Biology Chordata Class Actinopterygii Ecology Infraclass Teleostei Neopterygii Oncorhynchus nerka Pacific salmon Phylum Chordata Red Salmon Salmonidae Salmoniformes Salmoninae Seacam underwater housing Sockeye Salmon South Central Alaska Subclass Neopterygii Summer Teleost Teleostei United States Vertebrate aggression anadromous anadromy biological biosphere chordate diadromous diadromy fighting fresh water freshwater in situ living lotic migratory naturalworld nature organism semelparity semelparous stream under fresh water underwater underwaterphoto wild wild salmon
Spawning Coho Salmon including a jack
Coho Salmon (Oncorhynchus kisutch) including a jack commencing to spawn. Additional sneaker males entering the fray.
Actinopterygii Alaska Alaska wild salmon Animal Autumn Biology Chordata Class Actinopterygii Coho Salmon Ecology Infraclass Teleostei Neopterygii Oncorhynchus kisutch Pacific salmon Phylum Chordata Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon South Central Alaska Subclass Neopterygii Teleost Teleostei United States Vertebrate WPY2022 anadromous anadromous fish anadromy biological biosphere chordate diadromous diadromy fresh water freshwater in situ living lotic migratory naturalworld nature organism semelparity semelparous stream under fresh water underwater underwaterphoto 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.
Actinopterygii Alaska Alaska wild salmon Animal Autumn Biology Chordata Class Actinopterygii Coho Salmon Ecology Infraclass Teleostei Neopterygii Oncorhynchus kisutch Pacific salmon Phylum Chordata Reproductive behavior Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon South Central Alaska Subclass Neopterygii Teleost Teleostei United States Vertebrate anadromous anadromous fish anadromy biological biosphere chordate courtship diadromous diadromy fresh water freshwater in situ jack jack salmon living lotic migratory naturalworld nature organism precocial male precocious male salmonography.com semelparity semelparous spawning migration stream under fresh water underwater underwaterphoto 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.
Actinopterygii Alaska Alaska wild salmon Animal Biology Chordata Class Actinopterygii Ecology Infraclass Teleostei Neopterygii Oncorhynchus nerka Pacific salmon Phylum Chordata Red Salmon Salmonidae Salmoniformes Salmoninae Seacam underwater housing Sockeye Salmon South Central Alaska Subclass Neopterygii Teleost Teleostei United States Vertebrate anadromous anadromy biological biosphere chordate diadromous diadromy fresh water freshwater in situ jack jack salmon living lotic migratory naturalworld nature organism precocial male precocious male salmonography.com semelparity semelparous stream under fresh water underwater underwaterphoto 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.
Actinopterygii Alaska Alaska wild salmon Animal Biology Chordata Class Actinopterygii Coho Salmon Ecology Infraclass Teleostei Neopterygii Oncorhynchus kisutch Pacific salmon Phylum Chordata Salmonidae Salmoniformes Salmoninae Seacam underwater housing Silver Salmon South Central Alaska Subclass Neopterygii Teleost Teleostei United States Vertebrate anadromous anadromy biological biosphere chordate diadromous diadromy fresh water freshwater in situ jack jack salmon living lotic migratory naturalworld nature organism precocial male precocious male semelparity semelparous stream under fresh water underwater underwaterphoto wild wild salmon