Winter bird feeders: why sunflower hearts help garden birds

Across the Channel, many householders alter what they put in bird feeders to give birds better support during cold spells.

Birds in the garden are not simply looking for seeds. In the depths of winter, their priority is energy they can use quickly. This distinction, widely understood by British nature enthusiasts, affects which birds visit feeders and can also benefit species living close to homes in France.

Bird feeders designed as energy stores

The familiar image of an English garden alive with tits, finches and robins is not solely explained by the climate or by the presence of large hedges. It also reflects a widespread habit: offering food that matches birds' real seasonal needs.

In February, nights are still long and can be bitterly cold. Small passerines use a substantial proportion of their reserves simply to keep their body temperature stable. A blue tit, weighing only around 10 grams, needs to feed often if it is to get through the following night in good condition.

"The change is not about filling the feeder more, but about putting in food that is more concentrated and better chosen."

Low-cost mixes often include wheat, cracked maize or large seeds. These ingredients are not necessarily harmful, but much of them is frequently left on the ground. Smaller birds sort through them, ignore them or cannot always eat them easily.

Shelled sunflower seeds: an especially useful choice

The approach appealing to many gardeners in England is straightforward: favour seeds that are rich, effortless to access and unlikely to be wasted. Sunflower hearts, meaning seeds with their husks removed, meet this need particularly well.

They bring several benefits. Birds do not have to expend energy breaking open a husk, and can eat the nutritious part of the seed straight away. The ground also stays cleaner because husks do not build up beneath the feeder.

• Sunflower hearts suit tits, greenfinches, finches and nuthatches well.
• Niger seed, which is very fine, is more likely to attract goldfinches.
• Mixes containing fruit and small dried insects may appeal to robins.
• Fat cakes without nets provide lipids during cold periods.

This food is not a complete diet in itself. Birds will continue to look for insects, larvae, berries and wild seeds. A feeder serves as supplementary food, which is especially valuable when the ground is frozen or waterlogged.

Why lipids matter so much in winter

Lipids are energy reserves. In wild birds, they are used in particular to generate warmth and make up for long hours without food. A diet high in fat can therefore make a genuine difference in the middle of a cold snap.

Products should still be selected carefully. Very cheap fat balls sometimes contain large quantities of flour or ingredients of limited nutritional value. It is better to check the label and choose a simple recipe based on vegetable fat or suet, seeds and, where appropriate, dried insects.

"Plastic nets around fat balls should be avoided: feet and beaks can become trapped in them. A metal holder is much safer."

Adapting food to garden visitors

A generously stocked feeder can quickly become the domain of pigeons, crows or starlings. These species all have their place in nature, but they may monopolise food intended for smaller birds. The solution is to vary both feeder locations and feeding arrangements.

A tube feeder with small perches restricts access for larger birds. By contrast, a shallow dish on the ground, sheltered by a shrub, can help robins and blackbirds. These birds often prefer feeding near the ground rather than hanging from a feeder.

Common visitors	Suitable food	Recommended location
Tits	Sunflower hearts, fat, unsalted peanuts	Hanging feeder
Robins	Mealworms, fruit, soft food mix	Low, sheltered tray
Goldfinches	Niger seed	Feeder with small openings
Blackbirds	Pieces of apple, rehydrated raisins	Clear ground, out of cats' reach

Hygiene: the detail that protects the whole small colony

A dirty feeder can become a place where disease spreads. Damp conditions encourage mould, while droppings quickly collect on trays. The most careful British gardeners therefore clean their equipment regularly, particularly when it attracts large numbers of birds.

Washing weekly with hot water, then allowing everything to dry fully, reduces the risk. Wet seed, fermented food and scraps that have fallen to the ground should also be removed. If a bird appears extremely thin, lethargic or has abnormal plumage, it is best to stop feeding for a few days and thoroughly disinfect the equipment.

Water, even in cold weather

Water is often overlooked, despite being useful in every season. Birds need it for drinking and maintaining their feathers. A shallow container, cleaned often and set in an open spot, is enough. During frosts, replace the water rather than adding salt, sugar or alcohol, all of which can harm them.

Feeding is even more effective when it forms part of a wildlife-friendly garden. A native hedge, a few plants left to set seed, an area of fallen leaves and berry-bearing shrubs provide shelter and natural food. The feeder does not replace this habitat; it complements it.

As spring approaches, it is also advisable to cut back fatty foods gradually if temperatures rise for a sustained period. Birds then turn towards natural resources, while parents seek more protein to feed their young. Keeping a clean water source, allowing some vegetation to grow and avoiding pesticides are simple measures that extend the benefit of this winter care.