Fiscal Year
2014
Title
Research on the situation of fish reproduction in southern Iwate
Project and Theme
Project 1. Study on ecological succession of fisheries ground
Representative Organization: Tohoku University
Theme5. Studies on the coastal environment and marine resources in the southern part of Iwate Prefecture| Representative person | Ryusuke Kado |
|---|
| Organization | Kitasato University |
|---|
| Department | School of Marine Biosciences |
|---|
Research InformationPeriod and Interval2014/04/01 - 2015/03/31
monthly
Research Area
Okirai bay, Otsuchi bay, Noda bay, Sakari river
CategoryField survey
OverviewThe importance of the surf zone and the seagrass bed as a nursery ground for larval and juvenile fishes has widely recongnized. We examined species composition and dynamics of larval and juvenile fishes in the surf zone and the seagrass bed to estimate the impact of the 2011 disaster and recovery process from the disaster on the environment for fish reproduction in coastal area. We also examined dynamics of juvenile Japanese flounder in Otsuchi bay and Noda bay.
Overview of the Observation
Research Point Table
| Point | | Name | Urahama, Okirai bay |
|---|
| Name | Namiita, Okirai bay |
|---|
| Name | Otsuchi bay |
|---|
| Name | Noda bay |
|---|
|
|---|
Results and Future PlanWe examined species composition and dynamics of larval and juvenile fishes in the surf zone and the seagrass bed in Okirai bay to estimate the impact of the Tsunami disaster and recovery process from the disaster on the environment for fish reproduction in coastal area. A total of 2805 fish larvae and juveniles, representing at least 26 species from 21 families were collected in Okirai-Urahama site in Okirai bay. In 2013, we collected 15 families, 20 species, totaling 1504 individuals. The number of individuals increased with recovery of the surf zone. In seagrass bed in Okirai-Namiita site, we collected 16 families, 29 species, totaling 1008 individuals. The number of species is increased, but the number of individuals is decreased. The seagrass bed area is increased from 1200 to 3300 square meter. We compared the stomach fullness of juvenile Japanese flounders settled in two bays, Noda Bay and Otsuchi Bay. The fullness was much lower in Otsuchi Bay, and was suggested to be related with the enbayment of the bay, determining the food supply from outer sea. In Sakari river, we recognized increasing the number of Ayu, Plecoglossus altivelis in compared to that of in 2013.
Investigation Item and Data Acquisition
| Investigation Item | Data Acquisition |
|---|
| Environmental condition | Water temperature, Salinity, pH, DO, Turbidity |
| Fish (larvae and juveniles) | Species composition, Distribution |
| Seagrass bed | An area survey, Underwater photo images |
Reference
Person in charge of Investigation
| Representative person | Takashi Asahida |
|---|
| Organization | Kitasato University |
|---|
| Department | School of Marine Biosiciences |
|---|
| Representative person | Ken-ichi Hayashizaki |
|---|
| Organization | Kitasato University |
|---|
| Department | School of Marine Biosciences |
|---|
| Fiscal Year | 2014 |
|---|
| Organization | Kitasato University |
|---|
| Category | Field survey |
|---|
| Research Area | North Sanriku
South Sanriku
|
|---|
| Discipline | Ocean physics -> Water temperature
Ocean physics -> Salinity
Ocean physics -> Transparency / Turbidity
Ocean chemistry -> Salinity
Ocean chemistry -> Dissolved oxygen
Ocean chemistry -> pH
Ocean environment -> pH
Ocean biology / Ocean ecology -> Biological classification
Ocean biology / Ocean ecology -> Ecology
Ocean biology / Ocean ecology -> Fishes
Ocean biology / Ocean ecology -> Seaweed beds / Tidal flats distribution
|
|---|
