Reproductive ecology of native Japanese common carp revealed by genotyping of eggs attached to vegetation in Lake Biwa, Japan

2015 Fiscal Year Final Research Report

• Project/Area Number: 24510323
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Resource conservation science
• Research Institution: The University of Tokyo
• Principal Investigator: Kohji Mabuchi 東京大学, 大気海洋研究所, 助教 (50401295)
• Project Period (FY): 2012-04-01 – 2016-03-31
• Keywords: 在来種保全 / コイ / 琵琶湖 / 産卵

Outline of Final Research Achievements

The native Japanese strain of common carp has been dramatically affected by invasion of conspecific domesticated strains from Eurasia (introduced stains). Meanwhile, Lake Biwa, the largest freshwater body in Japan, harbors a relatively pure native population of common carp. In this study, reproductive ecology of the native population in Lake Biwa was investigated by genotyping of eggs attached to the vegetation in shallow coastal areas. The eggs were collected at a coastal area in Nagahama City during the reproductive season (from April to August). In the lake, water level is artificially controlled, being kept low after 16 June. Although the low water level reduces the shallow coastal areas in the lake, not a few eggs were obtained even in the low water level period (July and August). Four years (2012-2015) survey indicated that frequency of native strain egg in egg population tended to be higher in July and August than in April and May.

Free Research Field

魚類系統分類学