请教一道PREP里的语法题

there are legal limits on the size of cod and haddock that can be caught, but not for monkfish, which contributes to its depletion through overfishing.

不是说which不能指代前面整句话吗？这里为什么这么用？

我原本选的是

there are no legal limits, as there are for cod and haddock, on the size of monkfishes, a circumstance that contributes to their depletion through overfishing.

还有一道：

the company has unveiled what it claims is the world's smallest network digtal camcorder, which is as long as a handheld computer and weighs less than 11 ounces.

同样是which指代的问题，而且as long as 含义不单一啊…… 我选的是下面的

to be the world's smallest network digtal camcorder, the lenngth of which is that of a handheld computer, and it weighs

请各位牛人赐教~