adaptation: changes populations of organisms make over
evolutionary time to adjust to environmental changes. alevin:
larval salmon or steelhead from the time of hatching to the time
of absorption of the yolk sac. Alevins remain in the gravel.
adaptive management: changing program strategies to reflect
findings of monitoring and research to insure that resources are
invested in methods that are achieving greatest success.
alkaline: substances with a pH greater than 7.0 that form
corrosive substances in water, a high concentration of hydroxyl
(OH) ions. ammoecete: immature lamprey residing in fresh water.
anadromous: fish born in fresh water, migrating to the ocean
during adult phase but returning to fresh water to spawn.
anaerobic: processes not requiring oxygen or an environment
lacking oxygen. aquatic invertebrates: animals without skeletal
structures that reside in the water such as insects, snails,
crayfish, and amphipods. artificial culture (propagation): any
human assisted spawning and rearing of fish in