My swans are nesting and the straw they are using is kind of humid, here at my place rains a lot. is it necesary to put a ceiling made out of wood or any kind of protection ???? does eggs get rotten with humidity ?????? please help me out i really want my swans to have their cygnets.

What happens if the nest they are building i take it away and put new dry straw, and on top i put the shelter. i want to build right in the same place they where building the nest that is all humid (wet), would that be a problem ????

thank you.