Consequently , skipjack landings are poor , with the exception of ghana .
结果,除了加纳外,箭鱼的渔获量都很低。
Packed with ice , they try to catch a few tonnes of the more valuable sort of tuna , known as bigeye and yellowfin , while the bigger purse seiners like the playa de bakio , most of which are european , sweep up hundreds of tonnes of less valuable skipjack tuna outside somalia 's waters .