The Ecology of Larval and Metamorphosing Lampreys

摘要: The life cycle of lampreys typically begins in streams where fertilized eggs hatch into small, wormlike larvae (ammocoetes) which burrow soft stream bottoms they filter feed on organic matter until the onset metamorphosis. relative importance habitat variables can change with ammocoete size (and depending spatial scale measured), but must provide adequate substrate for burrowing and a regular supply suspended upon larval feed. Larval movement occurs significantly more often at higher densities warmer temperatures, downstream direction night. Sex ratio some lamprey species is related to differences density, proportion males increasing density. mortality thought be high egg phase, immediately following hatching, duration period has been found vary among within species, generally ranges from 3 7 years. However, analyses growth have hampered by unreliability age assessment methods lampreys. Metamorphosis during summer months, when water temperatures are most favorable, completed winter or early spring.