g'day david,

i've been mulling over this one mate, i'd realy hate to suggest one
thing and then have quiet the opposite happen especially if the fern
dies. before now i always had heaps of 'nidus' in my gardens and some
realy large ones.

in reality birds nests fern grow up in the trees and on rock edges
where they get heaps of water in the rain forests they prefer but then
they don't get flooded, so they will take a lot of water at the right
time sort of.

now if you had a falsh flood taht didn't deposit a huge amount of
sediment into the plant then it may do quiet well but there are too
many variables, flooded under water with no sediment for a few days is
most likely going to start them rotting, and then if you add sediment
which can be varioable that time could be shortened.

my suggestion keep them just above the flood line for preservation,
they can be mounted into a hollow log that is above the flood or mount
them into the fork of a tree above that level.

hope some of this makes sense and helps.
they won't like having their feet continually wet or saturated unlike
tree ferns. at best i would suggest they would cope with a flash flood
of no more than 24 hours.

len

snipped
--
happy gardening
'it works for me it could work for you,'

"in the end ya' gotta do what ya' gotta do" but consider others and the environment
http://hub.dataline.net.au/~gardnlen/