The time has come for swallows, martins and swifts to leave the UK and embark on their epic migration to South Africa, so make the most of the last few in the skies.
A final preen . . .
Swallows indicate the end of the summer when they depart for warmer climes and that is where our swallows are currently headed. They undertake an impressive 6000 mile migration between the UK and South Africa twice a year in search of food. They nest in the UK in the summer, but as they only feed on aerial insects (the majority of which are large flies, such as horseflies and bluebottles), their food source starts to run out in the autumn.
Faced with the prospect of little or no food, they start to head south during September and October.
It’s no walk in the park for these tiny birds as their extreme migration takes them south through Europe and across the Sahara desert.
They cover approximately 200 miles a day, generally at about 20mph – the maximum flight speed recorded was a whopping 35mph.
During their epic journey, swallows easily fall prey to starvation, exhaustion and extreme weather conditions, not to mention being trapped and killed in Southern Europe, the Middle East and North Africa in their hundreds of thousands during the migratory period. (The July issue of National Geographic covers the slaughter of birds in detail - don’t go there if you are at all squeamish)
. . . are we ready . . .
. . . let’s go.
See you on the other side of the world.
The disappearance of swallows and other migrants in the autumn was for long a great mystery. Some firmly believed that they hibernated at the bottom of lakes or ponds, and others that they hid and remained torpid until spring.
“In the Northern waters, fishermen often draw up in their nets an abundance of swallows, hanging together like a conglomerated mass. In the beginning of Autumn, they assemble themselves together in the reeds by ponds, where, allowing themselves to sink into the water, they join bill to bill, wing to wing and foot to foot.”
Olaus Magnus, History of the Northern Nations, 1550
But in 1776, in the Naturalist’s Journal, Gilbert White asked:
“But if hirundines (swallows) hide in rocks and caverns, how do they, while torpid, avoid being eaten by weasels and other vermin?"