smoltification
Juvenile salmon adaptation
Smoltification is the physiological transformation that prepares juvenile salmon and some trout for life in saltwater.
During this process, the young fish—called smolts—develop silvery coloring, change their body chemistry to tolerate salt, and undergo behavioral shifts that drive them downstream toward the ocean.
The hatchery timed its releases to coincide with natural smoltification.
Immature salmon with markings
- osmoregulationMaintaining internal solute balance
- gillsAquatic respiratory organs
- silveringDepositing reflective metal coating
- salinityDissolved mineral concentration
adaptation · hormones · cortisol · thyroid · metabolism · endocrine · pituitary · growth hormone
Anadromous North Sea fish
- Pacific salmonWest coast anadromous fish
- cohoNorth Pacific salmon species
- sockeyeAlaska's prized salmon
- steelheadAnadromous rainbow trout
trout · anadromous · juvenile · fingerling · alevin · fry · lifecycle · spawning
Movement to new territory
- predationHunting and consuming prey
- habitatOrganism's natural environment
- river flowWater's downstream movement
- estuaryTidal mixing zone
timing · environmental cues · daylength · water quality · climate change · conservation · mortality · corridor
Egg incubation facility
- tankLarge storage vessel
- rearingNurturing to maturity
- photoperiodDuration of daily light
- water temperatureWarmth of a liquid
feeding · stock · production · release · tagging · survival rate · grow-out · acclimation
parr
Immature salmon with markings
- osmoregulationMaintaining internal solute balance
- gillsAquatic respiratory organs
- silveringDepositing reflective metal coating
salinity · adaptation · hormones · cortisol · thyroid · metabolism · endocrine · pituitary · growth hormone · prolactin
Atlantic salmon
Anadromous North Sea fish
- Pacific salmonWest coast anadromous fish
- cohoNorth Pacific salmon species
- sockeyeAlaska's prized salmon
steelhead · trout · anadromous · juvenile · fingerling · alevin · fry · lifecycle · spawning · migration
migration
Movement to new territory
- predationHunting and consuming prey
- habitatOrganism's natural environment
- river flowWater's downstream movement
estuary · timing · environmental cues · daylength · water quality · climate change · conservation · mortality · corridor · watershed
hatchery
Egg incubation facility
- tankLarge storage vessel
- rearingNurturing to maturity
- photoperiodDuration of daily light
water temperature · feeding · stock · production · release · tagging · survival rate · grow-out · acclimation · disease resistance
- salmonAtlantic salmon, sockeye, chinook, pink salmon, coho