Throwing bread to the ducks is the simple sort of pleasure that parents love to pass on to their children, but now experts are throwing cold water on the practice.

Bread, they say, holds little nutritional value for birds, is a waste of their digestive juices and fills them up without doing them any good. Instead, those serious about dishing out treats should choose grated cheese, leftover jacket potatoes, breakfast cereals, crumbled biscuits and even cake.

The Royal Society for the Protection of Birds (RSPB) also recommends porridge oats, overripe strawberries, rice or scraps of pastry. Val Osborne, the RSPB’s head of wildlife inquiries, said: “There are many other household foods that would be much better for them. Bread doesn’t actually contain any of the vital ingredients to provide birds with the energy they need to breed and feed. The RSPB is asking people to consider alternatives such as porridge oats, cake crumbs and potatoes.”

The issue is said to be particularly important at this time of year when chicks are being raised. Filling their stomachs with bread will damage their chances of reaching adulthood, because they do not get the nutrients they need to grow.

The RSPB’s advice was aimed primarily at people who feed birds in their gardens, but with the approach of summer there were also concerns about the health of ducks, swans and other birds found on ponds and lakes.

Gemma Rogers, also of the RSPB, said that it did not matter whether the bread was mass-produced white or specialist Italian ciabatta. “They are all basically a filler, especially at the moment when the adult birds are flying back and forth to feed their young. It wouldn’t help them in any way.”

Breads that contain seeds will be marginally better for the birds than plain white or brown, but they are still too low in nutrients.

Seed cake and fruit loaf would be slightly better than a Victoria sponge but the sugar content would mean that any cake should be a useful source of energy.

Feeding birds in gardens has been increasingly important for wild birds in recent years and some species, including cirl buntings and tree sparrows, depend heavily on handouts for survival.

It is believed that the rise of the goldfinch to become one of the most frequent visitors to gardens is because more people are leaving out high-energy seeds for them.

Chris Packham, the naturalist and broadcaster, who is a vice-president of the RSPB, said that feeding the ducks was an important childhood experience. “I understand where they are coming from – bread is not the best thing to feed birds, but I would be reluctant to tell people to stop,” he said.

“One of my formative memories was being taken to a lake near Arun-del when I was about 4. I remember feeding the ducks – there was an extraordinary variety of shapes and colours. It was amazing.”

He said that the quality of commercial birdfood had risen dramatically. “If you are serious about feeding a bird you really have to put your hand in your pocket these days,” he added.

Table manners

— Food is best placed on a bird table that should have a rim to catch feed and a channel to allow rain water to drain away

— Mesh or tubular feeders can also be used but should be protected against foraging squirrels

— Ensure you place your feeder somewhere out of the reach of cats and other predators

— Mixture to feed birds can be made at home. Pinhead oatmeal and black sunflower seeds are suitable for most birds and make an excellent base

—Small seeds, such as millet, will attract house sparrows, dunnocks, finches, reed buntings and collared doves

— Flaked maize is favoured by blackbirds

— Crushed or grated peanuts will attract robins and wrens. Tits and greenfinches prefer whole peanuts and sunflower seeds

—Nyjer seeds are enjoyed by goldfinches and siskins

— Doves, pigeons and even pheasants are drawn to wheat and barley grains

— Split peas, beans, lentils and rice should be avoided as they can only be eaten by larger species

— Fat smeared on a trunk will attract nuthatches, treecreepers and woodpeckers. Try to provide water

Sources: RSPB; The Wildlife Trusts

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