Glossary F
- fin ray
- The segmented structures in a fin that provide support.
- fingerling
- A young or small fish, especially a young salmon or trout.
- fluvial
- A fish that hatches in a small tributary, rears there for 1-4 years, and then migrates out to a larger river to mature. The fish then migrates back to the tributary to spawn.
- frazil ice
- Ice formed in the water column in very cold temperatures. Frazil ice typically forms in shallow riffles where most of the heat in a stream is lost.
- fry
- Small fish, especially young, recently hatched fish.
- fusiform
- A streamlined body shape typical of most salmonines (trout, salmon and whitefish) which consists of a body which is taller than it is wide. This "torpedo" shape reduces resistance in the current allowing trout to hold position in a stream. An example of a fish with a non-fusiform body shape is the largescale sucker.
