Effect of elimination of Great Cormorants fDr conservation of inlandfisheries resource: Evaluation by multlple aPProaches

本文研究了日本伊豆半岛卡诺河流域大蝎的摄食生态。评估清除球茎的效果。对胃内容物和稳定同位素比值的分析结果表明，这些有害物质主要捕食居住在卡诺河流域的淡水鱼类。种群普查结果表明，从夏季到初冬，卡诺河很可能是鹈鹕的主要觅食地，而不考虑混血儿的灭绝和鹈鹕群体位置的变化。有必要引入不同的方法来防止鹈鹕的摄食损害。

Feeding ecology of Great Cormorants in the Kano River basin, the lzu Peninsula, Japan, was examinedt。evaluate the effect of elimination of the corm。rants for the conservation of lnland fisheries resources.The results in analyses of stomach contents and stable isotope ratios showed that the corrnorants preyedmainly onfreshwator fishes inhabiting the Kano River watershed. The results in population censusesshowed that the Kano River is likely the main feeding ground for the cormorants from summer to earlywinter, irrespective of execution of elimination for the commorants and the change of location of cormorant colonies. It is necessary to introduce different methods for prevention of the feeding damagesby the cormorants.