Outdoor column: Can ducks transfer fish eggs between water bodies?

Investigation: Field Farm Duck Eggs

Three Birds That Follow Rivers

Mallards Ferry Fish Eggs Between Waterbodies Through Their Poop

Pooping ducks can shed the live eggs of fish

Goldfinches are a welcome splash of color at our backyard feeders

Fish eggs can survive ducks eating them and hatch if excreted

Duck Legs, Fish Eggs and a Persistent Myth

Fish Eggs Can Hatch After Being Eaten And Pooped Out By Ducks - Moldy Chum

Do Ducks need a pool of water in their pen? - Quora

Fish eggs can hatch even after being eaten and excreted by ducks - The Washington Post

Guide to Raising Chickens, Ducks and Geese - Grit