Watersheds
Glossary

ADECAlaska Department Environmental Conservation
ADF&GAlaska Department of Fish and Game
ADNRAlaska Department of Natural Resources
AlevinLarval salmonid hatchling with yolk sac still attached. Alevin reside in the redd (nest) until the yolk sac is absorbed and they emerge from the gravel.
AnadromousFish which migrate from the sea, where they grow and mature, into freshwater where they spawn.
Anadromous Waters Catalog and AtlasListing of "various rivers, lakes and streams or parts of them" of the state that are important for the spawning, rearing or migration of anadromous fishes.
BufferArea of vegetation that is maintained around a water body to protect against impacts from the uplands and provide cover for animals that live in the riparian area
CoverAnything that provides protection or refuge from predators or adverse conditions
DebrisMiscellaneous scattered or accumulated material; may originate from natural or human source
DepositionSettlement of materials out of the water column and onto the stream bottom
DiversityNumbers of different plants or animals in a community
EcologyStudy of living organisms in their environment
EcosystemA community including plants, animals, microorganisms and their non-living environment which interacts with each other
EPAU.S. Environmental Protection Agency
FryImmature life stage of fish. Emergent fry leave the salmonid redd (nest) and become free-swimming. Salmonid fry may rear in freshwater for one to three (occasionally more) years.
HabitatPlace where a plant or an animal lives which provides life functions, including reproduction, food, escape, and migration.
Large organic/ woody debrisRelatively large piece of stable, woody material that intrudes into a water body; complex or irregular woody debris is better for fish.
Marine NutrientsOrganisms accumulate and store nutrients as they grow. Anadromous fish feed on marine organisms, store the nutrients from marine foods in their body, and release the nutrients in freshwater after they spawn.
Passage (for fish)Movement by fish upstream or downstream at all flow levels, that is not prevented by water velocity and/or physical blockage(s).
ReachA specified homogeneous length of a stream.
ReddPit-like nest dug in the gravel of a stream bottom by a female fish where eggs are laid, fertilized by the male and re-covered with gravel.
Riparian Of, on, or relating to the banks of a natural course of water; area or zone that is between the aquatic and upland areas; may be periodically flooded.
RiprapLayer of large material - usually rock - placed on a bank to protect it; or, the material itself.
SalmonidFish family that includes salmon, trout, whitefish and grayling.
SedimentMaterial weathered from rocks or decomposition of organic material and transported by water or air; or, deposited from water or air or accumulated on a substrate.
SmoltSalmonid migratory life stage that transforms the freshwater rearing life stage for survival in saltwater.
SubstrateMaterial on the bottom of a water body.
ThalwegLongitudinal line along a stream bottom that follows the deepest part of the channel.
WatershedA watershed is an entire region (or "basin"), which drains into a river or river system. A watershed typically includes several sub-basins with components from the mountains to the sea: glaciers, tributaries, lakes, wetlands, and estuaries.
WetlandArea that may be flooded periodically; usually, with soil or vegetation characteristics different from adjoining non-flooded areas

If you would like more information concerning Watersheds, please contact jessica.johnson@alaska.gov, Habitat Biologists, Alaska Department of Fish and Game.