Barn swallows are the most widespread of all the swallow species and this little bird also has the largest natural distribution of any of the world’s songbirds.
Loved for their acrobatic flying skills and with a distinctive forked tail and blue coat, barn swallows are a welcome visitor to many parts of the globe heralding the arrival of spring and the end of winter time.
Swallows have a varied diet but flying insects make up the bulk of it at 99% so they are known as insectivores. They catch on the wing and will spend hours darting about hoovering up insects particularly when they have young to feed in the nest. The insects that swallows eat depend on where they have migrated to. Swallows only feed during the day not at night.
Swallows are capable of the most remarkable aerobatic displays – they are nature’s acrobats and finding airborne food sources on the wing is pretty effortless for this species.
Dietary restriction for a swallow tends to be as the result of climatic conditions which alter or limit the available insect life.
Swallow with captured insect
The diet of a swallow will vary depending on whether the bird is in the UK, North America or Europe. Here are some of the insects swallows eat:-
Swallows will also eat caterpillars, grasshoppers, crickets, spiders, snails and worms.
Swallow feeding juvenile
Swallows have a broad, wide beak and mouth which is ideal for scooping insects as they fly. The insects are guided into the swallow’s open mouth with the help of short rictal bristles which border the beak.
The swallows’ amazing aerobatic skills mean this bird can use a range of flying patterns and manoeuvres to catch virtually any insect on the wing. Their flight behaviour will depend on the insects available which in turn is directly linked to weather conditions.
Swallows are often seen as nature’s natural cleanser of unwanted insects and eat on average 60 insects an hour. But swallows do also eat insects which are welcome visitors to gardens like bees and butterflies.
Different weather conditions will produce flying insects at varying levels so on humid days, swallows will tend to hunt lower down but are also capable of flying much higher into the atmosphere on clear sunny days to look for food competing with other birds like swifts.
Swallows are acrobatic in flight
Swallows do eat bird seed but are not big fans of garden bird feeders as they prefer to look for food and eat on the wing rather than remain static when they feed.
Occasionally a swallow will come to rest on the ground to peck seed but they can be vulnerable to predators like birds of prey and domestic cats.
There is so much insect life available that swallows don’t tend to need to look beyond what they can catch on the wing and only resort to other food sources if insects are scarce.
Mealworms are not a natural food source for swallows but if their usual diet is scarce then they may be persuaded to feed on them.
Juvenile Swallow with insect
Swallows do eat bees and often prefer to catch larger insects as the nutritional return is greater from a large insect compared to the energy expenditure. However, swallows do prefer to avoid insects which sting and they tend only to predate on bees, wasps and hornets if their regular food source is under pressure.
Swallows will eat strawberries occasionally and if blackberries are early and they have not migrated then they will also help themselves to a plump juicy berry or two.
Baby swallows are fed relentlessly by their parents whilst they are in the nest which on average, is for around one month.
Baby Swallows generally are mostly fed insects. Both parents feed them and bring back a proportion of the food they catch meaning the adults have to work even harder with their feeding requirements when there is a clutch of chicks to feed. If the weather is cold and some early nests can struggle during cold springs, then the adult swallows will forage for berries or anything else they can find to feed their young.
Swallow chicks that do not receive enough nutrition due to climatic conditions can die.
Barn Swallow feeding baby swallows (chicks)
Swallows don’t tend to eat eggs from other species. Unmated male barn swallows will kill and eat other baby birds in order to split up the resident pair of adults in order to attract and mate with the female.
Swallows don’t tend to feed on insects associated with water or pond life like tadpoles.
Barn swallows will supplement their insect diet with a small amount of grit or eggshells to aid digestion.
In the UK, the food source for barn swallows dries up in the autumn so they migrate 6,000 miles to Africa in search of warmer climes and more insects.
Swallows drink on the wing, finding a level in the atmosphere where there is water available. They will also catch raindrops whilst they perch or skim low over water sources like puddles, ponds and rivers.
Swallow drinking water from a lake
Seed and berries will attract swallows either on the ground or on open feeder platforms, but the bigger lure is foliage and flora which encourages a plentiful supply of their own natural food source which is insects.
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