¡@Bony flyingfish (Hirundichthys oxycephalus) is the primary component of flyingfish-egg fishery captures in the northeastern waters of Taiwan, and is also one of the dominant species of flyingfish in eastern waters of Taiwan. In recent years, people are conscious of overfishing in negarding to the continuously decreasing flyingfish resources. For rational management and sustainability of the fishery, there is an urgent need to study age and growth of the fish. Based on the laboratory-reared fish from the fertilized eggs collected in the wild, the daily periodicity of growth increments in three pairs of otoliths (lapillus, sagitta and asteriscus) was validated. First growth increment formed in the first day after hatching for sagitta and lupillus, and was in the eleven day after hatching for Asteriscus.
¡@¡@Ages of the wild flyingfish sample of 5.4~229.1 mm FL collected by drifted gillnets in Hualian, Taitung, Lyudao and Lanyu waters during April 2009 to March 2010, were determined by daily growth increment (DGI) counting in asteriscus, as adjusted by an addition of 11 DGIs. The von Bertalanffy growth parameters of the fish were estimated to be 253.9 mm in asymptotic length and 0.00753 mm d-1 in growth coefficient. Use DGIs estimation hatch date from otolith ringing, and estimated spawning date by deduct from 3 day hatch requisition. we found 2 recruitment group in eastern Taiwan within a year, most fish hatched either in summer or winter.
In this study showing that bony flyingfish was an grew fast and had long longevity sp., therefore, on fishery management, we should decrease the fishing pressure and give them enough surplus biomass, so the biomass could recover rapidly. And we found two recruitment group, one could behalf of stock from east taiwan, and maybe it could behalf of two stocks ,on the other hand the method of fishery management should be a quite different .We suggest to confirm by the further reproductive biology research.
| Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0727110-154222 |
| Date | 27 July 2010 |
| Creators | Lin, Chung-hui |
| Contributors | Meng-hsien Chen, Shui-kai Chang, Jen-chieh Hsiao, Chih-wei Chang |
| Publisher | NSYSU |
| Source Sets | NSYSU Electronic Thesis and Dissertation Archive |
| Language | Cholon |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0727110-154222 |
| Rights | unrestricted, Copyright information available at source archive |
Page generated in 0.002 seconds