Their problems are exacerbated by the large area of ocean space that they have to control and the migratory nature of fish stocks, and the mobility of the fishing vessels that target these stocks. The fishing industry has also become more highly organized and sophisticated.
这些问题又由于他们要控制的海洋区域辽阔和鱼类资源的回游性质以及针对这些鱼群的渔船的流动性而更加严重。