. Bulletin. Science. MATING BEHAVIOR OF SPOTTED SAND BASS 23. Fig. 3. A male Paralabrax maculatofasciatus in the position near the mid-dorsal region of a gravid female just prior to a vertical spawning rush to the surface. a pair spawn and is later interrupted by a male (sneaker) that joins as the original pair make their vertical turn to begin the spawning rush towards the surface. The sneaker, therefore, joined in the spawning rush and in subsequent gamete release. In one observation of a sneak spawn, the sneaker was observed colliding with and displacing the original courting male in close
. Bulletin. Science. MATING BEHAVIOR OF SPOTTED SAND BASS 23. Fig. 3. A male Paralabrax maculatofasciatus in the position near the mid-dorsal region of a gravid female just prior to a vertical spawning rush to the surface. a pair spawn and is later interrupted by a male (sneaker) that joins as the original pair make their vertical turn to begin the spawning rush towards the surface. The sneaker, therefore, joined in the spawning rush and in subsequent gamete release. In one observation of a sneak spawn, the sneaker was observed colliding with and displacing the original courting male in close proximity to the female. Spawning Times and Coloration The mean duration of all spawning bouts was 127 seconds (range sec). The mean spawning rush for the captive adults lasted 4 sec, measured from the vertical turn (that terminated courtship) to gamete release. Spawning was observed from 1745-1945 hr in T3 (Figure 6). Most spawns (83%) occurred after 1900 hr, however, two spawns occurred at 1850 and 1854 hr. Sundown times during the observation period began at 1922 hr and ended at 1853 hr (Figure 5). The mean spawn time for the eight-fish group was 1906 hr (+31 min), 12 minutes before sunset (1918 hr). The mean time of spawning for the five-fish group was 1924 hr (+ min), 31 min after sunset (1853 hr). Activity patterns were noticeably different between the sexes. In the late after- noon (1700-1800), females were observed swimming, most frequently near the top of the tank. By 1900, females were less active and their abdomens began to swell. As time progressed, the genital papilla of females with swollen abdomens began to protrude (Figure 7). Males were also less active in the late afternoon, becoming more active as the spawning period approached. During courtship, fe-. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly res
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