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Ducks Eat Fish

Dear Birds Folks,

I thought ducks only ate bread, corn, etc. Then today I came upon a tidal pool where several mallards were gorging themselves on tiny fish trapped in the shallow water. Which do they prefer, bread or fish?

– Sid, Orleans, MA


Both, Sid,

Mallards prefer both and you shouldn’t be surprised. After all, we eat both, too. Anyone who orders a Filet-O-Fish at McDonald’s eats bread and fish at the same time. Fish sandwiches are quite popular at many fast food restaurants, except for perhaps one place. One restaurant serves something called a “Fishamajig” and I don’t care how hungry I am, I’m not saying “Fishamajig” in public…or even in private. What were they thinking?

With an estimated population of twelve million birds, Mallards are the most common and most widespread wild ducks in North America. They are found in every state, across Canada and even in Greenland (which, apparently, is not for sale). In addition, Mallards breed throughout Europe, Asia, North Africa and Australia. They are clearly one of the most successful waterfowl species in the world. One of the keys to their success is that they aren’t fussy eaters. Whether it’s animal or vegetable, if it’s available, they’ll eat it. The list of foods Mallards eat is extremely long (perhaps not as long as a CVS receipt, but nothing’s that long). On the list you’ll find corn, barley, wild rice, domestic rice, Rice-A-Roni (maybe), plus snails, tadpoles, insects and yes, fish…but probably not Fishamajigs. (What were they thinking?)

Unfortunately, Mallards have paid a price for their lack of culinary discrimination. For centuries hunters have used lead shot when hunting ducks. When the pellets miss the birds, the lead settles to the bottom of ponds, lakes and marshes. After the shooting has stopped and there is peace again in the valley, returning Mallards mistakenly ingest the lead shot while feeding in the mud. This is not good. Thousands of Mallards (and other ducks) die annually after ingesting lead. In order to save the ducks, and other wildlife, lead shot has been mostly outlawed. That is good. Unfortunately, the same people who wanted to buy Greenland are also trying to roll back many of these important environmental safeguards. Sad.

Surprisingly, the Mallard’s larger cousin, the Canada Goose, is a far pickier eater. It wants nothing to do with fish, snails, tadpoles or any of those other slimy things. Geese have done the research and they’ve come to the correct conclusion that a plant-based diet is the healthier option (which explains why there are so many of them). One of my co-workers has both ducks and geese as pets. (Don’t ask me why.) He tells me that whenever he moves a water bucket or kicks over a log, the ducks will come running to scoop up any exposed earwigs, sow bugs or worms. Meanwhile, his geese just stand back, watch the action and think, “Eew! Ducks are disgusting.” They have a point. Instead, geese eat grass, grains and other plants, which are far less repulsive…until you see what comes out of the other end.

There is one thing, however, that both ducks and geese love and it’s not really good for them. I’m talking about the aforementioned bread. Good ol’ bread, the staff of life, has long been suspected of causing waterfowl to develop a deformity known as “angel wing.” At first, angel wing sounds like it should be a good thing. Who wouldn’t want to have the wings of an angel? But in this case, the wings become deformed. Instead of lying flat, they stick out like cowlicks. Sometimes the birds may even lose their ability to fly. Ducks afflicted with angel wing are most often found in parks and other areas where humans routinely feed birds. Experts have long debated the relationship between bread (and other non-natural foods) and angel wing. Nevertheless, too much bread, even on a fish sandwich, is not recommended for ducks, or geese or anybody.

This brings up the old question about feeding ducks: Should we do it? The short answer is, nah. This is a strange position coming from a guy who sells birdseed for a living, but putting out food for waterfowl is different than feeding songbirds. How so, you ask? The birds we see on our feeders spend much of their day venturing around their home range. Only a percentage (25%) of what “feeder birds” consume actually comes from feeders. The majority of what they eat is natural. This is not the case when supplemental feeding draws large numbers of ducks to a single pond. It doesn’t take long for them to consume all of the natural food, especially in the winter. Once that is gone, the birds become focused on handouts (bread, chips, popcorn), which often aren’t real healthy. There is also a concern about spreading avian diseases. Too many birds eating, sleeping and pooping in the same shallow water is never good. All right, enough of that; back to the Mallards.

The reason why we don’t see more Mallards eating fish, Sid, is because, unlike deep diving ducks, Mallards aren’t built for fishing. Instead, they are opportunists, exploiting whatever food source comes their way. They’ll eat plants in a pond, or sow bugs under a water bucket or fish trapped in a tidal pool. And in a pinch, they’ll even eat a Fishamajig, but they won’t say it out loud. That’s where they draw the line.