2013 Fiscal Year Final Research Report
Origin and evolution of freshwater amphidromy: Suggestion of a new migration type
| Project/Area Number |
23580246
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Multi-year Fund |
|---|
| Section | 一般 |
|---|
| Research Field |
General fisheries
|
|---|
| Research Institution | Nihon University (2013)
The University of Tokyo (2011-2012) |
|---|
Principal Investigator |
WATANABE Shun 日本大学, 生物資源科学部, ポスト・ドクトラル・フェロー (60401296)
|
|---|
| Project Period (FY) |
2011 – 2013
|
| Keywords | ボウズハゼ / 黒潮 / 分散 / 初期生活史 / 淡水性両側回遊 / 温帯 / 熱帯 / 生活史戦略 |
|---|
| Research Abstract |
During ecological research of Sicyopterus japonicus, which is the only temperate species of the subfamily Sicydiinae, we found larval dispersion by Kuroshio Current, an essential larval dependence on growth in the ocean, and a lack of landlocked or fluvial forms. Their larval dispersion in the ocean and life history characteristics in the river has played a role in the temperate distribution of this species. The Sicydiine larval stage in tropical areas may be required to occur in the ocean for all species, but ayu, sculpins and galaxiids in temperate areas have landlocked or fluvial forms with larvae that do not need to enter the ocean for larval feeding and growth. This suggests that Sicydiine larvae have a high oceanic dependency, whereas ayu, sculpins and galaxiid larvae have a low oceanic dependency. Freshwater amphidromous fish in tropical and temperate areas appear to have developed two different strategies in the evolution of their life histories.
|
