Robber in fishing version of Settlers

Question

In the fishing addition to Settlers of Catan the robber can be removed from the board by using two fish. The question then is can a knight from the pack of Development cards be used to bring the robber back into the game by putting it on an opponents resource?

My question is not answered by the first respondant as in the fish game the desert is replaced by a lake and the robber is move completely off the board with two fish. The question then is can the knight bring the robber back into play from this position?

Answer 1

The rules (here) actually state that for two fish you may:

Move the robber back to the desert (do not steal any cards)

It isn't removed from the board, but is placed on the desert (where it has no effect). A knight may still then move it as normal.

Answer 2

The lake tile replaces the desert. With no desert tile, the robber starts out off of the board and moves onto the board when a 7 is rolled or someone uses a Knight card.

If the robber has been removed from the board (using fish), the same rules apply: a Knight or rolling 7 will bring him right back. There is no way to remove the robber "permanently."