When Do Swallows Arrive In UK – The Complete Guide To British Swallow Migration

When Do Swallows Arrive in UK Territories?

UK swallows head south for the winter, as insects are not warm-blooded like birds and thus unable to be active during the winter. This means that swallows must head south to find enough food in the winter. However, when the weather warms in the spring, the swallows return to raise their young. So, when do swallows arrive in UK territories to prepare for the breeding season?

Swallows typically return to the United Kingdom when the snow melts and insects return. Therefore, the earliest migrants usually arrive in late March, and peak numbers appear in late April. However, there are a few February records of swallows in the UK, and it is thought that climate change is allowing these birds to arrive earlier and remain later into autumn.

Okay, you should now be familiar with how to answer the question, “When do swallows arrive in UK territories?”. However, the question, “When do swallows migrate?” is also one that deserves some answers. Let’s consider when swallow migration takes place. 

When Do Swallows Migrate In Autumn?

Autumn is a time when swallows will begin to gather into groups following their breeding season. Speaking of autumn, when do swallows migrate from UK territories during this time of year? In other words, when do swallows leave the UK each year? 

Well, after swallows have reproduced in the summer, they abandon their nests and begin staging for their fall migration.

Therefore, both mature swallows and young will gather at favourable feeding locations and spend a few weeks fattening up before they start to head south. Okay, this explains what swallows do immediately after the breeding season, but when do swallows leave the UK?

Great question – the southbound migration for swallows often begins in August, with peak migration occurring in September. Most Western House-Martins depart from the United Kingdom by October, although a few stragglers remain until early November. Likewise, Bank Swallows, being the tiniest British swallow, must also leave the UK by November.

Barn Swallows are the last British swallow species to linger in autumn, with decent numbers remaining through October. Most Barn Swallows depart by mid-November, but some remain until December.

Where Do Swallows Migrate To In Winter?

The United Kingdom is not a suitable wintering location considering the diets of swallows, so where do swallows migrate to in winter?

Of course, swallows will choose a warm location with an abundance of insects during winter. Therefore, the three swallow species that breed in the UK have evolved to winter in sub-Saharan Africa. Here, they enjoy warm weather and no shortage of insects to eat.

Barn Swallows have a massive range in the winter, with some travelling to magical destinations like the Philippines and India. However, those who breed in the United Kingdom will not winter here. Instead, some will winter in Spain and northern Algeria, but the majority of those who breed in the UK winter in sub-Saharan Africa. Likewise, the entire populations of UK Western House-Martins and Bank Swallows winter in sub-Saharan Africa.

Got it? Great! However, you may now ask, “Where do swallows migrate to in the summer other than the UK?”. Well, swallows can be found in most of the northern hemisphere in the summer. Yes, these aerial insectivores are happy to take advantage of the seasonal abundance of insects in much of the northern reaches of the globe. 

Why Do Swallows Migrate?

You may be thinking that it sounds like swallows live pretty good lives on their wintering grounds, so why do swallows migrate in the first place?

Recall that we’ve already discussed why swallows migrate from the UK; the cold and snow that winter brings means that British swallow species lose the insects that they require to survive. However, why do swallows migrate to the United Kingdom in spring if they seemingly have all of their needs met on their wintering grounds?

Although swallows have pretty good lives at the locations in which they winter, there is much more competition during the summer compared to the United Kingdom. In other words, it is much more difficult to find nesting sites and secure food for baby swallows during summer in sub-Saharan Africa because there are far more breeding birds here compared to the UK.

While swallow migration can be treacherous, the payoff is big for UK swallows. Here, these birds gorge themselves on insects during summer and find nesting locations with relative ease.

How Far Do UK Swallows Migrate?

You’ve surely gathered that swallows in the UK undergo long migratory flights annually, but how far do swallows migrate?

Despite their tiny size, these songbirds are well-equipped for making long-distance flights during their swallow migration. Indeed, British swallow species have streamlined bodies and long wings that allow them to stay airborne with ease. In fact, they are so adept at navigating the skies that many wonder, “Do swallows ever land?”.

Swallows do–indeed–land, but they may remain airborne for several consecutive days as they migrate to or from their UK breeding grounds. These incredible feats of swallow migration may require birds to fly for more than 3,000 kilometres one way, meaning that some swallows may fly more than 6,500 kilometres during their annual migrations.

How Long Do Swallows Live?

After reading about the intense migrations that UK swallows experience twice a year, you may be curious about swallow lifespans. How long do swallows live?

It should not be too surprising that swallows do not enjoy the lengthy lifespans of other birds. Like other small birds, swallows live brief but productive lives in which they can raise more than a dozen offspring in the few years that they’re around.

Swallows are faced with many perils in their lives. For instance, they must contend with predators like sparrowhawks, chemical contamination of prey and habitat, climate change, loss of habitat, habitat alterations, and more. Moreover, the long migratory flights that they make can turn deadly if they encounter bad weather.

If not for these threats, swallows may be able to survive for more than 10 years. However, a more accurate answer to the question, “How long do swallows live?”, would be only a few years. In fact, most swallows fail to reach adulthood.