Posted: 14/01/2016 at 21:08
Are they deep beds? Does it flood normally or is this a once in 20 year flood?
If the beds are likely to get carried away regularly, I would only do shallow beds, so the roots can get well down into the subsoil and might survive.
For bird friendly, cotoneasters, rowan trees, even an apple tree or two. Blackbirds love windfalls. Buddlejas are easy to propagate and will attract butterflies.