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Hokkaido University Collection of Scholarly and Academic Papers >
Graduate School of Environmental Science / Faculty of Environmental Earth Science >
Peer-reviewed Journal Articles, etc >
Growth parameters of endangered freshwater pearl mussel (Margaritifera laevis, Unionoida)
| Title: | Growth parameters of endangered freshwater pearl mussel (Margaritifera laevis, Unionoida) |
| Authors: | Akiyama, Yoshihiro B Browse this author | | Iwakuma, Toshio Browse this author |
| Keywords: | growth models | | Gompertz function | | annuli | | maximum shell length | | life-span | | conservation |
| Issue Date: | Dec-2009 |
| Publisher: | E. Schweizerbart'sche |
| Journal Title: | Fundamental and Applied Limnology / Archiv für Hydrobiologie |
| Volume: | 175 |
| Issue: | 4 |
| Start Page: | 295 |
| End Page: | 305 |
| Publisher DOI: | 10.1127/1863-9135/2009/0175-0295 |
| Abstract: | We observed periodic increments of the annuli to verify the annual growth-age relationship in two populations of a freshwater pearl mussel, Margaritifera laevis (Bivalvia, Unionoida), in northern Japan and confirmed that one annulus is added each year. The relationship between yearly shell growth and age was regarded as a unimodal distribution. We fitted several growth models to the shell length-age relationships of these two populations, which had different densities and age distributions. The Gompertz function showed the best fit, in terms of both RSS (residual sum of squares) and the difference between the observed maximum shell length and the asymptotic shell length. The life span of M. laevis was shorter than that reported for Margaritifera margaritifera populations at higher latitudes (≥50°N), which have been widely recognized as threatened. Margaritiferid mussels living at lower latitudes tend to have shorter life spans and smaller maximum size. These results suggest that margaritiferid mussels in southern regions such as M. laevis in Japan and M. margaritifera in Spain may be particularly vulnerable when conditions are unsuitable for juvenile mussels for prolonged periods. |
| Type: | article (author version) |
| URI: | http://hdl.handle.net/2115/43042 |
| Appears in Collections: | 環境科学院・地球環境科学研究院 (Graduate School of Environmental Science / Faculty of Environmental Earth Science) > 雑誌発表論文等 (Peer-reviewed Journal Articles, etc)
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Submitter: 秋山 吉寛
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