For many British bird enthusiasts, noticing the arrival of the Swallow on home shores is a surefire sign that spring is well underway and the balmy evenings of summer are just over the horizon.
Most of you will probably have noticed these agile little birds by now, with the British Trust for Ornithology's migration blog recording sightings from around April 2nd and logging "good numbers" as of April 16th.
Of course, it depends on where in the country you happen to be as to when they arrive (colder regions might not see them until late April or early May some years), but with sightings in Birmingham on April 24th, Malton in North Yorkshire on the same date and the Mid Ulster area on April 9th, it's safe to say that most parts of the country should now have their Swallows back.
Swallows are small birds with blue-black backs, white breasts, red on their heads and throats and tails that reach out in long streamers behind them.
Unusually, both sexes are quite similar - the females are not stuck with duller colours than the males in this species. The tails of males are a little longer, though.
You can find them over open pastures where there are plenty of insects and access to nesting sites in farm buildings, but a reduction in habitats is driving them closer to humans than would once have been the case.
They spend most of their time in flight and their astonishingly agile swoops are likely to impress you if you take the time to watch. It's easy to confuse Swallows with similar House Martins and Swifts, but Swallows tend to feed at lower heights and have longer tails, while House Martins have obvious white rumps and Swifts are dark all over.
Swallows and breeding
Before mating, both expectant Swallow parents construct a nest from mud and pieces of twig, but they don't use trees like many British birds. Instead, they go for beams in barns and underneath shelves in outbuildings.
They will also save their energy by reusing old nests - in some cases, the RSPB has recorded existing sites being reused for almost 50 years.
Once hatched, chicks are fed with insects by both parents in the nest. However, when they're fledged, they must learn to receive food from the parents' beaks while still on the wing - that's what we call in-flight refuelling!
Why aren't they here all year?
Swallows migrate at the end of British summertime to get away from the cold weather, which causes their food supply of insects to dwindle or be cut off completely.
They arrive back here anytime from March onwards, and usually start their long journey to Africa in September or October depending on the weather. Some particularly mild years have resulted in them staying until late October and even the first frosts of early November though.
In the autumn, it's a bittersweet sight to see them begin a feeding frenzy to double their weight and then line telegraph wires in their hundreds. All of a sudden, you'll notice they have gone apparently overnight, which means they have begun their 6,000-mile trip to South Africa.
The tiny birds fly over the UK to France, across Spain and then over to Morocco. Amazingly, they then traverse the Sahara Desert into Nigeria. After that, their exact route isn't clear, but it's thought they fly over remote Central Africa before finally arriving in South Africa.
However, since we're going into summer soon, our Swallows have just done the reverse leg of this trip and so are delighting us with their presence once again.
How you can help Swallows at home
Unfortunately, Swallow numbers aren't as healthy as they once were due to climate change, habitat loss in their winter homes, trapping in Africa and the western Mediterranean and changes in farming practices in the UK.
As a result, they're now on the Amber List as a species of conservation concern. Although they won't eat off your bird tables like Blue Tits and Sparrows, there are some things you can do to help them.
Firstly, provide them with potential nest sites in your garage, shed or outhouse by making a small opening to let them get in and out safely. You can then affix a nest platform for stability and put in one of our open Swallow Nest Boxes.
If we get a very hot summer, you can keep the temperature down for the chicks inside by soaking an old piece of carpet in water and placing it on the roof directly above the nest - try not to disturb the site or go back too frequently, though.
Secondly, aim to encourage insect numbers in your local area by planting wildflower seeds - even if you haven't seen Swallows nearby, every little bit of habitat corridor counts.
Let us know if you've seen Swallows near where you live so far in 2015!