SPAWNING SEASONALITY OF ALBACORE, THUNNUS-ALALUNGA, IN THE SOUTH-PACIFIC OCEAN

The spawning seasonality of albacore, Thunnus alalunga, in the South P acific was studied by examining ovaries and testes collected from long line vessels operating in the waters off New Caledonia (21 degrees-23 degrees S, 164 degrees-166 degrees E) and Tonga (16 degrees-29 degrees S, 171 degrees-177 degrees W), January 1990 to February 1992. The mon thly change in GSI values and mean oocyte diameters indicated that alb acore are annual spawners, with most spawning limited to the austral s ummer months from November to February. Asymmetry in weight of, but no t in the reproductive development of, the left and right gonad pairs w as apparent in samples from the two collection sites; most right ovari es and testes were heavier and larger than those on the left side.