It seems harmless enough, feeding bread to the ducks in your local park; we enjoy it, the ducks get some food, and everyone’s happy. In fact, in England and Wales alone, we feed six million loaves of bread to ducks every year – but this is definitely doing them more harm than good. Most bread is essentially junk food to them, although white is the worst, and can cause a range of problems, including a debilitating disease called “angel wing.”
White bread has essentially no nutritional value – it’s packed full of calories and has little else to offer. Continuously feeding it to birds causes them to rely on us for a food source rather than their natural diet. It’s the equivalent of only feeding your children unhealthy foods; they’ll eventually get addicted to it, and will find it very difficult eating, or wanting to eat, anything else. So, at the very least, feeding ducks bread is giving them a readily-accessible unhealthy diet, leaving them ultimately malnourished.
At the far end of the spectrum, there’s “angel wing.” This is a disturbing condition that causes the bird’s wings to point out laterally, rather than resting against the body, rendering them in many cases unable to fly. It’s an incurable condition brought about as a result of a high-calorie diet, one extremely high in protein and carbohydrates, and low in vitamins D, E and manganese – the exact diet a bird would get if they primarily ate white bread. Without being able to fly, these birds soon die.
Image credit: The angel wing condition seen on a Muscovy duck. Cengland0/Wikimedia Commons; CC BY 3.0
The effect of lobbing bread into the canals and ponds across the land goes far beyond the detrimental effects on the health of water fowl: It pollutes waterways, causing poisonous algal blooms, promoting the growth of suffocating molds, and attracts infection-riddled vermin to the area.
“Of course, bread's not the only thing that causes the problem,” says Richard Bennett, an environmental manager at the Canal and River Trust, as reported by the Guardian. “It wouldn't matter if you fed ducks in a clear, nutrient-free environment like an upland stream, but people are more likely to do it in towns and cities.”