Such inefficiency could contribute to declines in their numbers .

这种低效率可能会促使鱼的数量下降。

Some economists expect further declines as the economy weakens .

一些经济学家预计随着经济的削弱还将进一步下跌。

Compensation declines will be broad-based .

薪酬的下滑将具有普遍性。

But he declines to elaborate .

但他拒绝详细说明。

Declines in incomes are not always followed by political instability .

收入的减少并不总会导致政治上的不稳定。