I remember the children’s book from years ago, and have since seen many groups of wild Mallard ducklings roaming ponds and lakes in the US, including at Murphey Candler Park.
Mallards and most other ducks sift through silt and mud for small invertebrates and certain plant matter using their extremely sensitive bills, which have a comb-like system around the edge of the inner beak with plenty of nerve endings to detect food.
It’s already cute when adult ducks wriggle their mouths around in search of sustenance, but when babies d something it’s almost always cuter. So make way for these ducklings!