Md. Robards et al., Maturation, fecundity, and intertidal spawning of Pacific sand lance in the northern Gulf of Alaska, J FISH BIOL, 54(5), 1999, pp. 1050-1068
Pacific sand lance Ammodytes hexapterus in Kachemak Bay, Alaska, showed no
sexual dimorphism in length-to-weight (gonad-free) ratio or length-at-age r
elationship. Most matured in their second year, males earlier in the season
than females, but females (31%) attained a higher gonadosomatic index than
males (21%). Sand lance spawned intertidally once each year in late Septem
ber and October on fine gravel or sandy beaches soon after the seasonal pea
k in water temperatures. Sand lance in Cook Inlet and Prince William Sound
displayed similar maturation schedules. Schools were dominated 2 : 1 by mal
es as they approached the intertidal zone at a site where spawning has take
n place for decades. Sand lance spawned vigorously in dense formations, lea
ving scoured pits in beach sediments. Fecundity of females (93-199 mm) was
proportional to length, ranging from 1468 to 16 081 ova per female. About h
alf of the overall spawning school fecundity was derived from age group 1 f
emales (55% of the school by number). Spawned eggs were 1.02 mm in diameter
, demersal, slightly adhesive, and deposited in the intertidal just below t
he waterline. Sand lance embryos developed over 67 days through periods of
intertidal exposure and sub-freezing air temperatures. (C) 1999 The Fisheri
es Society of the British Isles.