nedhart 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?

No, they can't live on grass alone. They need bugs!

Here is a good explanation of duck nutrtition

"Newly hatched ducklings feed almost exclusively on invertebrates. This
includes everything from earthworms to small crustaceans, snails, and insect
larvae and adults. Invertebrates provide a concentrated source of protein and
fat required by a rapidly growing animal. By the time ducklings are about 2
weeks old, or one-quarter grown, they begin to consume a diet that is more
adult like. In some species this is still mostly invertebrates; in others, it
is mostly plant matter. Invertebrate availability influences where a hen will
take her brood. Very often people find a mallard nest close to a particular
wetland and then are concerned because the eggs hatched, but the brood never
appeared on their wetland. Many folks think that this means that something
killed the ducklings, but in many cases it simply means that the hen took the
brood to another wetland that had richer invertebrate resources. Such wetlands
may be as far as 3 miles away from the nest. The ducklings don't have to feed
while they are hiking to the "brood pond" because they have a "yolk sack" that
contains the remainder of the egg yolk. The yolk sack contains enough nutrient
reserves to keep the ducklings going for about 3 days after they hatch. The
need for invertebrates also explains why very young broods are seldom seen on
large lakes. Because water levels are relatively stable on such lakes,
nutrients do not recycle rapidly enough to support the large invertebrate
populations required by broods. Also, such lakes are likely to hold fish
populations that may compete with ducklings for the limited invertebrates
available there. This is one reason that shallow marshes are so valuable to
waterfowl production."

From http://www.npwrc.usgs.gov/help/faq/birds/duckseat.htm


k30a