Coexistence of anadromous and resident life history styles of pond smelt, Hypomesus nipponensis, in Lake Ogawara, Japan, as determined by analyses of otolith structure and strontium : calcium ratios

• Published in: Environmental biology of fishes 2000-06, Vol.58 (2), p.195-201
• Main Authors: KATAYAMA, S, RADTKE, R. L, OMORI, M, SHAFER, D. J
• Format: Article
• Language: English
• Subjects: Agnatha. Pisces; Biological and medical sciences; Brackish; Fish; Freshwater; Fundamental and applied biological sciences. Psychology; Hatching; Hypomesus nipponensis; Japan; Japan, Ogawara L; Lakes; Life history; Marine; Ponds; Strontium; Vertebrates: general zoology, morphology, phylogeny, systematics, cytogenetics, geographical distribution
• ISSN: 0378-1909; 1573-5133
• DOI: 10.1023/A:1007682729460

Anadromous and resident forms of pond smelt, Hypomesus nipponensis, were found to occur in sympatry in Lake Ogawara, Japan. Profiles of Sr: Ca ratios from individuals could be grouped to two patterns (1) a 'resident' pattern with low Sr: Ca ratios from core to edge and (2) an 'anadromous' pattern with relatively low Sr: Ca ratios near the core with abrupt increases in ratios at a location approximately 0.3mm from the core. Spawners smaller than 60mm standard length (SL) were resident, between 60 to 80mm were mixed resident and anadromous, and larger than 80mm were anadromous. Anadromous individuals first migrated after 40 to 82 days from hatching (mean±sd, 59.1±13.5d) and 14.6 to 30.9mm SL (22.2±5.3mm). There was no difference in SL between resident and anadromous individuals during age at first migration, suggesting that size may not be the mechanism for divergence of alternative life history styles.[PUBLICATION ABSTRACT]