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学術研究成果リスト

Detail of Grant Awarded Academic Researches

Project

Genetic biological resouces in the Tama River: native fish populations and their life hisotries

Academic
Research
No.363
Principal
Investigator
Tatsuki YOSHINAGA
Affiliation School of Marine Biosciencs, Kitasato University
Research
Summary

To clarify the genetic and ecological characteristics of fishes in the Tama River, (1) we compared the life histories of genetically different Japanese dace in the upper and lower reaches. The results showed that the downstream population had a oceanic life stage, while the upstream populations were land-locked. (2) Genetic characterization of salmonid fishes indicated that the Oncorhynchus masou complex consisted of three haplotypes, one of which may be the native population of this river. (3) Carp had four genotypes, one of which was native in Japan, but had morphological characteristics of introduced one, , suggesting that this discrepancy was caused by hybridization. (4) The Cottus pollux complex was genetically identified as a large-egg type, and information on sex ratio and maturity was obtained. (5) The benthic fauna of the eight stations surveyed showed that the number of families differed greatly, providing basic information for evaluating fish habitat.


Collaborators

Hitoshi IDA
Fumiya OKUYAMA
Fumiaki SHIROTORI

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