Proximate composition at various stages of adult life in the Southern Hemisphere lamprey, Geotria australis gray

1. 1. At the end of the marine trophic phase in Geotria australis, the lipid content (as % wet body weight) was very high in the whole animal (21%) and in the liver (38-40%). 2. 2. During the very long spawning-run period (ca 16 months), vast changes take place in the relative and absolute values for the lipid, water and protein content of the whole animal and its muscle, liver and gonad. 3. 3. 1552 and 1654 kJ were expended during the spawning-run period by females and males respectively. 447 kJ were transferred to the ovary. 4. 4. Comparisons are made between our data for G. australis and those obtained for holarctic lampreys. © 1983