Maturation, fecundity, and intertidal spawning of Pacific sand lance in the northern Gulf of Alaska

Citation
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
Citations number
50
Categorie Soggetti
Aquatic Sciences
Journal title
JOURNAL OF FISH BIOLOGY
ISSN journal
00221112 → ACNP
Volume
54
Issue
5
Year of publication
1999
Pages
1050 - 1068
Database
ISI
SICI code
0022-1112(199905)54:5<1050:MFAISO>2.0.ZU;2-6
Abstract
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.