In europe , mainly capelin , sandeel , mackerel and norway pout are used for fish meal production .
在欧洲，主要用毛鳞鱼，沙丁鱼，鲭与挪威鳕来生产鱼粉。
Big fish such as cod , tuna , and groupers have declined worldwide by two-thirds while the number of anchovies , sardines and capelin has surged in their absence , said university of british columbia researchers .
