| 1. | Fewer herring than usual have been landed this year .
今年鲱鱼捕获量比往年少。 |
| 2. | Fewer herring than usual have been landed this year
今年鲱鱼捕获量比往年少 |
| 3. | 3 we choose unit time the maximum sustainable yield as the management objectie ; ?
3以单位时间最大可持续捕获量为管理目标； 3 |
| 4. | In theareas around the protected regions fishermen reported catching , onaverage , four times as many fish per trip as previously
在保护区周边海域，渔民们上报的单次捕获量比起之前的量平均高出3倍。 |
| 5. | 2 we choose the maximum sustainable yield as the management objective ; we choose the maximum sustainable economic rent as the management objective in
2以最大可持续捕获量为管理目标； 2 3以最大净利润为管理目标； 2 |
| 6. | In [ 26 - 30 ] , the optimal harvesting policies that maximized the sustainable yield for autonomous single - species harvesting models were studied
文献[ 26 - 30 ] ，讨论了自治单种群捕获模型，以最大可持续捕获量为管理目标，得到了最优捕获策略 |
| 7. | In [ 21 - 25 ] , the optimal harvesting policies for autonomous single - species harvesting models were studied , which maximized the sustainable yield and economic rent respectively
文献[ 21 - 25 ] ，讨论了自治单种群捕获模型，分别以最大可持续捕获量和最大净利润为管理目标，得到了最优捕获策略 |
| 8. | The hauls of these commercially desirable species are dwindling , and the sizes of individual fish being taken are getting smaller ; a large number are even captured before they have time to mature
这些经济鱼种的捕获量逐渐缩水，鱼的个体也越来越小，其中有许多鱼甚至还来不及长大就被捉起来了。 |
| 9. | That means a higher proportion of what is in the sea is being caught , so the real difference between present and past is likely to be worse than the one recorded by changes in catch sizes
参考译文：这意味着更高比例的海洋生物正在遭到捕获，因此今昔之间的真正差别可能比通过捕获量的变化记录的差别更大。 |
| 10. | The optimal harvesting policies that maximized the sustainable yield for nonautonomous single - species harvesting models , which had a unique globally asymptotically stable periodic solution , were obtained by fan meng [ 15 ] and li hailong [ 16 ]
文献[ 15 ] [ 16 ]讨论了非自治单种群捕获模型，在周期解存在唯一及全局渐近稳定前提下，为获得最大可持续捕获量，而得到最优捕获策略 |
