Great Basin Naturalist


Various aspects of the reproduction and embryology of Walker Lake Lahontan tui chub, Gila bicolor, were investigated during the spring–summer period of 1976, 1977, and 1981. Tui chub were found to spawn in littoral regions of the lake beginning in late May or early June. Early in the season male chub substantially outnumbered females over the spawning grounds, with a normal 1:1 sex ratio gradually approached as the season progressed. The developmental period between fertilization to hatch-out was shortened by increases in water temperature. Selected stages of embryonic development are described from egg fertilization through post-hatch.