Hello

I am working for a customer with a large courtyard. There is no pond
or source of water. The only water comes from puddles left after it
rains and runoff from AC condensation that exits through a rubber
hose. The only thing that grows here is grass. The canadian geese
that hatched a few weeks ago seem to be doing fine, they are
constantly eating grass and have grown, but today I saw two very young
duckings straying pretty far from their mother and they looked feeble.
They were pecking at the grass but not pulling any of it. One of
them was even pecking at goose droppings. I am wondering if they can
live on grass like the geese, and if not, if there is something I can
give them to eat. Any ideas?