An introduction of Stock Enhancement in Kanagawa, Japan Provincial Court, Bruges, Belgium 7-8 May,2007 Toshitame IMAI Kanagawa Prefectural Fisheries Technology Center Yoroshi, Jogashima, Misaki, Miura Kanagawa , Japan

A location of Kanagawa

Total landing of fisheriesRatio of each fish species in total landing Landings of commercial and sports fishing in Kanagawa

Brief History of Stock Enhancement Activities in Kanagawa Prefecture 1966 Establishment of R/D facility of hatchery technology 1967 R/D of live feed culture & larviculture 1974 ～ Fundamental studies on fishery biology of the red sea bream, the Japanese flounder, and abalone 1975 Development of the technologies on mass production of live feed and a mechanical bottom cleaner 1976 The 1 st hatchery for stock enhancement R/D of large scale larviculture technologies 1977 （ Rotifer fortification examination, water tank bottom vacuum cleaner device development) 1978 ～ Large scale restocking activity of red sea bream using 1million hatchery-raised juveniles, tagged 10% juveniles 1986 Tag and recapture experiment on hatchery-raised red sea bream juveniles

1984 Enforcement of the 1st basic plan for stock enhancement （ The 5 th plan, 2006) 1987 A pilot proof examination (recovery ratio, cost- effectiveness, benefit principle ratio) 1989 An association of Kanagawa Fish Farming Foundation established 1990 Investigation of measures on the management of stock enhancement of marine resources ( setting an closed fishing area, season, releasing a small fish) 1990 Construction of the 2nd hatchery for stock enhancement 2000 Introducing a benefit principle system Brief History of Stock Enhancement Activities in Kanagawa Prefecture, contn’d

A promotion system of sea farming Board of director Secretariat Management sec. Operation sec. CaputInspector Support City Town Assoc. Kanagawa Fish farming Found. Kanagawa Pref. Fish. Tec. Center Coop. Play fishing Boat supplier Fishe rmen Angler Support Member. Organization of Fish farming found

An aerial photograph of Kanagawa Prefectural Fisheries Technology Center

Cultivation Tank of Rotifer and Green Water

Rearing Tank and Drain Cage, Bottom Cleaner

Development of Red Sea bream

Releasing Hatchery Raised Red Sea Bream

A Sports Fishing Boat of Red Sea Bream in Tokyo Bay

Landing sight on Fish market

Measurement of red sea bream

Target species of stock enhancement in Kanagawa Prefecture Red: Association production Yellow: purchase from outside Black: Technology Center production Blue: Discontinue

Annual changes of stocking number

Recapture rate of stock enhancement

Cost-effectiveness

‘66’78 ‘00 The catch by commercial and sports fishermen and the number of released juveniles of red sea bream in Kanagawa Prefecture.

A ratio of hatchery-raised fish and wild fish in landing Hatchery wild Thousand indi.

Development of a tagging method for a fry We attached an anchor tag to red sea bream fry with length 6-8cm since 1978 to 1989 and released 1,000,000 of them in total. The recapture rate was 1%. Movement, growth became clear by anchor tag planting of fish. However, a calculation of a recovery was not possible by falling off of a tag, and lacking of a recapture report.

Development of a marking method for a fry Furthermore, we developed a new technology using ALC as a mark to a fry, and to dye a scale. A method to make a mark in alizalin complexone stained an otolith conventionally Optical microscope Fluorescent microscope

The deformity of inter-nostril epidermis as a mark of hatchery-raised fish

A contribution breakdown of an endowment A sum of an endowment 761,170 thousand yen

A change of an income breakdown of Association of Kanagawa fish farming Foundation Thousand yen

The ratio of seeds production capital before and after inducing cooperate money from the red sea bream fishing angler Before After After Total \29,290,143 Total \32,100,

Development of Zostera bed Shallow waters of Tokyo Bay had very large eelgrass ground until 1960’s. However, reclaim advanced for high economic growth after 1960’s, and shallow waters level lost it. As a result, the seat which larvae of fishery products brought up disappeared, and quantity of fishery decreased sharply. Therefore we perform a trial to restore eelgrass ground

The genetic selection of stocks used for restocking purposes In addition,we pay it around 20% for the parent in every year and perform a substitute We coast the number of parent fish more than 500 of them to keep genetic variety We monitor mt-DNA and microsatellite DNA about a gene of a released fish and a fishery fish now. Haprotype composition

Thank you very much for your kind attention